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A library jar that provides APIs for Applications written for the Google Android Platform.

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/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.preference;

import static androidx.annotation.RestrictTo.Scope.LIBRARY;
import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP;

import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.os.Parcel;
import android.os.Parcelable;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.AbsSavedState;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;

import androidx.annotation.CallSuper;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RestrictTo;
import androidx.core.content.ContextCompat;
import androidx.core.content.res.TypedArrayUtils;
import androidx.core.view.accessibility.AccessibilityNodeInfoCompat;
import androidx.recyclerview.widget.RecyclerView;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;

/**
 * Represents the basic Preference UI building
 * block displayed by a {@link PreferenceFragmentCompat} in the form of a
 * {@link RecyclerView}. This class provides data for the
 * {@link android.view.View} to be displayed
 * in the list and associates with a {@link SharedPreferences} to
 * store/retrieve the preference data.
 * 

* When specifying a preference hierarchy in XML, each element can point to a * subclass of {@link Preference}, similar to the view hierarchy and layouts. *

* This class contains a {@code key} that will be used as the key into the * {@link SharedPreferences}. It is up to the subclass to decide how to store * the value. * *

*

Developer Guides

*

For information about building a settings UI with Preferences, * read the Settings * guide.

*
* * @attr name android:icon * @attr name android:key * @attr name android:title * @attr name android:summary * @attr name android:order * @attr name android:fragment * @attr name android:layout * @attr name android:widgetLayout * @attr name android:enabled * @attr name android:selectable * @attr name android:dependency * @attr name android:persistent * @attr name android:defaultValue * @attr name android:shouldDisableView * @attr name android:singleLineTitle * @attr name android:iconSpaceReserved */ public class Preference implements Comparable { /** * Specify for {@link #setOrder(int)} if a specific order is not required. */ public static final int DEFAULT_ORDER = Integer.MAX_VALUE; private Context mContext; @Nullable private PreferenceManager mPreferenceManager; /** * The data store that should be used by this Preference to store / retrieve data. If null then * {@link PreferenceManager#getPreferenceDataStore()} needs to be checked. If that one is null * too it means that we are using {@link android.content.SharedPreferences} to store the data. */ @Nullable private PreferenceDataStore mPreferenceDataStore; /** * Set when added to hierarchy since we need a unique ID within that * hierarchy. */ private long mId; /** * Set true temporarily to keep {@link #onAttachedToHierarchy(PreferenceManager)} from * overwriting mId */ private boolean mHasId; private OnPreferenceChangeListener mOnChangeListener; private OnPreferenceClickListener mOnClickListener; private int mOrder = DEFAULT_ORDER; private int mViewId = 0; private CharSequence mTitle; private CharSequence mSummary; /** * mIconResId is overridden by mIcon, if mIcon is specified. */ private int mIconResId; private Drawable mIcon; private String mKey; private Intent mIntent; private String mFragment; private Bundle mExtras; private boolean mEnabled = true; private boolean mSelectable = true; private boolean mRequiresKey; private boolean mPersistent = true; private String mDependencyKey; private Object mDefaultValue; private boolean mDependencyMet = true; private boolean mParentDependencyMet = true; private boolean mVisible = true; private boolean mAllowDividerAbove = true; private boolean mAllowDividerBelow = true; private boolean mHasSingleLineTitleAttr; private boolean mSingleLineTitle = true; private boolean mIconSpaceReserved; /** * @see #setShouldDisableView(boolean) */ private boolean mShouldDisableView = true; private int mLayoutResId = R.layout.preference; private int mWidgetLayoutResId; private OnPreferenceChangeInternalListener mListener; private List mDependents; private PreferenceGroup mParentGroup; private boolean mWasDetached; private boolean mBaseMethodCalled; private final View.OnClickListener mClickListener = new View.OnClickListener() { @Override public void onClick(View v) { performClick(v); } }; /** * Interface definition for a callback to be invoked when the value of this * {@link Preference} has been changed by the user and is * about to be set and/or persisted. This gives the client a chance * to prevent setting and/or persisting the value. */ public interface OnPreferenceChangeListener { /** * Called when a Preference has been changed by the user. This is * called before the state of the Preference is about to be updated and * before the state is persisted. * * @param preference The changed Preference. * @param newValue The new value of the Preference. * @return True to update the state of the Preference with the new value. */ boolean onPreferenceChange(Preference preference, Object newValue); } /** * Interface definition for a callback to be invoked when a {@link Preference} is * clicked. */ public interface OnPreferenceClickListener { /** * Called when a Preference has been clicked. * * @param preference The Preference that was clicked. * @return True if the click was handled. */ boolean onPreferenceClick(Preference preference); } /** * Interface definition for a callback to be invoked when this * {@link Preference} is changed or, if this is a group, there is an * addition/removal of {@link Preference}(s). This is used internally. */ interface OnPreferenceChangeInternalListener { /** * Called when this Preference has changed. * * @param preference This preference. */ void onPreferenceChange(Preference preference); /** * Called when this group has added/removed {@link Preference}(s). * * @param preference This Preference. */ void onPreferenceHierarchyChange(Preference preference); /** * Called when this preference has changed its visibility. * * @param preference This Preference. */ void onPreferenceVisibilityChange(Preference preference); } /** * Perform inflation from XML and apply a class-specific base style. This * constructor of Preference allows subclasses to use their own base style * when they are inflating. For example, a {@link CheckBoxPreference} * constructor calls this version of the super class constructor and * supplies {@code android.R.attr.checkBoxPreferenceStyle} for * defStyleAttr. This allows the theme's checkbox preference * style to modify all of the base preference attributes as well as the * {@link CheckBoxPreference} class's attributes. * * @param context The Context this is associated with, through which it can * access the current theme, resources, * {@link android.content.SharedPreferences}, etc. * @param attrs The attributes of the XML tag that is inflating the * preference. * @param defStyleAttr An attribute in the current theme that contains a * reference to a style resource that supplies default values for * the view. Can be 0 to not look for defaults. * @param defStyleRes A resource identifier of a style resource that * supplies default values for the view, used only if * defStyleAttr is 0 or can not be found in the theme. Can be 0 * to not look for defaults. * @see #Preference(Context, android.util.AttributeSet) */ public Preference(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { mContext = context; final TypedArray a = context.obtainStyledAttributes( attrs, R.styleable.Preference, defStyleAttr, defStyleRes); mIconResId = TypedArrayUtils.getResourceId(a, R.styleable.Preference_icon, R.styleable.Preference_android_icon, 0); mKey = TypedArrayUtils.getString(a, R.styleable.Preference_key, R.styleable.Preference_android_key); mTitle = TypedArrayUtils.getText(a, R.styleable.Preference_title, R.styleable.Preference_android_title); mSummary = TypedArrayUtils.getText(a, R.styleable.Preference_summary, R.styleable.Preference_android_summary); mOrder = TypedArrayUtils.getInt(a, R.styleable.Preference_order, R.styleable.Preference_android_order, DEFAULT_ORDER); mFragment = TypedArrayUtils.getString(a, R.styleable.Preference_fragment, R.styleable.Preference_android_fragment); mLayoutResId = TypedArrayUtils.getResourceId(a, R.styleable.Preference_layout, R.styleable.Preference_android_layout, R.layout.preference); mWidgetLayoutResId = TypedArrayUtils.getResourceId(a, R.styleable.Preference_widgetLayout, R.styleable.Preference_android_widgetLayout, 0); mEnabled = TypedArrayUtils.getBoolean(a, R.styleable.Preference_enabled, R.styleable.Preference_android_enabled, true); mSelectable = TypedArrayUtils.getBoolean(a, R.styleable.Preference_selectable, R.styleable.Preference_android_selectable, true); mPersistent = TypedArrayUtils.getBoolean(a, R.styleable.Preference_persistent, R.styleable.Preference_android_persistent, true); mDependencyKey = TypedArrayUtils.getString(a, R.styleable.Preference_dependency, R.styleable.Preference_android_dependency); mAllowDividerAbove = TypedArrayUtils.getBoolean(a, R.styleable.Preference_allowDividerAbove, R.styleable.Preference_allowDividerAbove, mSelectable); mAllowDividerBelow = TypedArrayUtils.getBoolean(a, R.styleable.Preference_allowDividerBelow, R.styleable.Preference_allowDividerBelow, mSelectable); if (a.hasValue(R.styleable.Preference_defaultValue)) { mDefaultValue = onGetDefaultValue(a, R.styleable.Preference_defaultValue); } else if (a.hasValue(R.styleable.Preference_android_defaultValue)) { mDefaultValue = onGetDefaultValue(a, R.styleable.Preference_android_defaultValue); } mShouldDisableView = TypedArrayUtils.getBoolean(a, R.styleable.Preference_shouldDisableView, R.styleable.Preference_android_shouldDisableView, true); mHasSingleLineTitleAttr = a.hasValue(R.styleable.Preference_singleLineTitle); if (mHasSingleLineTitleAttr) { mSingleLineTitle = TypedArrayUtils.getBoolean(a, R.styleable.Preference_singleLineTitle, R.styleable.Preference_android_singleLineTitle, true); } mIconSpaceReserved = TypedArrayUtils.getBoolean(a, R.styleable.Preference_iconSpaceReserved, R.styleable.Preference_android_iconSpaceReserved, false); mVisible = TypedArrayUtils.getBoolean(a, R.styleable.Preference_isPreferenceVisible, R.styleable.Preference_isPreferenceVisible, true); a.recycle(); } /** * Perform inflation from XML and apply a class-specific base style. This * constructor of Preference allows subclasses to use their own base style * when they are inflating. For example, a {@link CheckBoxPreference} * constructor calls this version of the super class constructor and * supplies {@code android.R.attr.checkBoxPreferenceStyle} for * defStyleAttr. This allows the theme's checkbox preference * style to modify all of the base preference attributes as well as the * {@link CheckBoxPreference} class's attributes. * * @param context The Context this is associated with, through which it can * access the current theme, resources, * {@link android.content.SharedPreferences}, etc. * @param attrs The attributes of the XML tag that is inflating the * preference. * @param defStyleAttr An attribute in the current theme that contains a * reference to a style resource that supplies default values for * the view. Can be 0 to not look for defaults. * @see #Preference(Context, AttributeSet) */ public Preference(Context context, AttributeSet attrs, int defStyleAttr) { this(context, attrs, defStyleAttr, 0); } /** * Constructor that is called when inflating a Preference from XML. This is * called when a Preference is being constructed from an XML file, supplying * attributes that were specified in the XML file. This version uses a * default style of 0, so the only attribute values applied are those in the * Context's Theme and the given AttributeSet. * * @param context The Context this is associated with, through which it can * access the current theme, resources, {@link android.content.SharedPreferences}, * etc. * @param attrs The attributes of the XML tag that is inflating the * preference. * @see #Preference(Context, AttributeSet, int) */ public Preference(Context context, AttributeSet attrs) { this(context, attrs, TypedArrayUtils.getAttr(context, R.attr.preferenceStyle, android.R.attr.preferenceStyle)); } /** * Constructor to create a Preference. * * @param context The Context in which to store Preference values. */ public Preference(Context context) { this(context, null); } /** * Called when a Preference is being inflated and the default value * attribute needs to be read. Since different Preference types have * different value types, the subclass should get and return the default * value which will be its value type. *

* For example, if the value type is String, the body of the method would * proxy to {@link TypedArray#getString(int)}. * * @param a The set of attributes. * @param index The index of the default value attribute. * @return The default value of this preference type. */ protected Object onGetDefaultValue(TypedArray a, int index) { return null; } /** * Sets an {@link Intent} to be used for * {@link Context#startActivity(Intent)} when this Preference is clicked. * * @param intent The intent associated with this Preference. */ public void setIntent(Intent intent) { mIntent = intent; } /** * Return the {@link Intent} associated with this Preference. * * @return The {@link Intent} last set via {@link #setIntent(Intent)} or XML. */ public Intent getIntent() { return mIntent; } /** * Sets the class name of a fragment to be shown when this Preference is clicked. * * @param fragment The class name of the fragment associated with this Preference. */ public void setFragment(String fragment) { mFragment = fragment; } /** * Return the fragment class name associated with this Preference. * * @return The fragment class name last set via {@link #setFragment} or XML. */ public String getFragment() { return mFragment; } /** * Sets a {@link PreferenceDataStore} to be used by this Preference instead of using * {@link android.content.SharedPreferences}. * *

The data store will remain assigned even if the Preference is moved around the preference * hierarchy. It will also override a data store propagated from the {@link PreferenceManager} * that owns this Preference. * * @param dataStore the {@link PreferenceDataStore} to be used by this Preference * @see PreferenceManager#setPreferenceDataStore(PreferenceDataStore) */ public void setPreferenceDataStore(PreferenceDataStore dataStore) { mPreferenceDataStore = dataStore; } /** * Returns {@link PreferenceDataStore} used by this Preference. Returns {@code null} if * {@link android.content.SharedPreferences} is used instead. * *

By default preferences always use {@link android.content.SharedPreferences}. To make this * preference to use the {@link PreferenceDataStore} you need to assign your implementation * to the Preference itself via {@link #setPreferenceDataStore(PreferenceDataStore)} or to its * {@link PreferenceManager} via * {@link PreferenceManager#setPreferenceDataStore(PreferenceDataStore)}. * * @return the {@link PreferenceDataStore} used by this Preference or {@code null} if none */ @Nullable public PreferenceDataStore getPreferenceDataStore() { if (mPreferenceDataStore != null) { return mPreferenceDataStore; } else if (mPreferenceManager != null) { return mPreferenceManager.getPreferenceDataStore(); } return null; } /** * Return the extras Bundle object associated with this preference, creating * a new Bundle if there currently isn't one. You can use this to get and * set individual extra key/value pairs. */ public Bundle getExtras() { if (mExtras == null) { mExtras = new Bundle(); } return mExtras; } /** * Return the extras Bundle object associated with this preference, * returning null if there is not currently one. */ public Bundle peekExtras() { return mExtras; } /** * Sets the layout resource that is inflated as the {@link View} to be shown * for this Preference. In most cases, the default layout is sufficient for * custom Preference objects and only the widget layout needs to be changed. *

* This layout should contain a {@link ViewGroup} with ID * {@link android.R.id#widget_frame} to be the parent of the specific widget * for this Preference. It should similarly contain * {@link android.R.id#title} and {@link android.R.id#summary}. *

* It is an error to change the layout after adding the preference to a {@link PreferenceGroup} * * @param layoutResId The layout resource ID to be inflated and returned as * a {@link View}. * @see #setWidgetLayoutResource(int) */ public void setLayoutResource(int layoutResId) { mLayoutResId = layoutResId; } /** * Gets the layout resource that will be shown as the {@link View} for this Preference. * * @return The layout resource ID. */ public final int getLayoutResource() { return mLayoutResId; } /** * Sets the layout for the controllable widget portion of this Preference. This * is inflated into the main layout. For example, a {@link CheckBoxPreference} * would specify a custom layout (consisting of just the CheckBox) here, * instead of creating its own main layout. *

* It is an error to change the layout after adding the preference to a {@link PreferenceGroup} * * @param widgetLayoutResId The layout resource ID to be inflated into the * main layout. * @see #setLayoutResource(int) */ public void setWidgetLayoutResource(int widgetLayoutResId) { mWidgetLayoutResId = widgetLayoutResId; } /** * Gets the layout resource for the controllable widget portion of this Preference. * * @return The layout resource ID. */ public final int getWidgetLayoutResource() { return mWidgetLayoutResId; } /** * Binds the created View to the data for this Preference. *

* This is a good place to grab references to custom Views in the layout and * set properties on them. *

* Make sure to call through to the superclass's implementation. * * @param holder The ViewHolder that provides references to the views to fill in. These views * will be recycled, so you should not hold a reference to them after this method * returns. */ public void onBindViewHolder(PreferenceViewHolder holder) { holder.itemView.setOnClickListener(mClickListener); holder.itemView.setId(mViewId); final TextView titleView = (TextView) holder.findViewById(android.R.id.title); if (titleView != null) { final CharSequence title = getTitle(); if (!TextUtils.isEmpty(title)) { titleView.setText(title); titleView.setVisibility(View.VISIBLE); if (mHasSingleLineTitleAttr) { titleView.setSingleLine(mSingleLineTitle); } } else { titleView.setVisibility(View.GONE); } } final TextView summaryView = (TextView) holder.findViewById(android.R.id.summary); if (summaryView != null) { final CharSequence summary = getSummary(); if (!TextUtils.isEmpty(summary)) { summaryView.setText(summary); summaryView.setVisibility(View.VISIBLE); } else { summaryView.setVisibility(View.GONE); } } final ImageView imageView = (ImageView) holder.findViewById(android.R.id.icon); if (imageView != null) { if (mIconResId != 0 || mIcon != null) { if (mIcon == null) { mIcon = ContextCompat.getDrawable(getContext(), mIconResId); } if (mIcon != null) { imageView.setImageDrawable(mIcon); } } if (mIcon != null) { imageView.setVisibility(View.VISIBLE); } else { imageView.setVisibility(mIconSpaceReserved ? View.INVISIBLE : View.GONE); } } View imageFrame = holder.findViewById(R.id.icon_frame); if (imageFrame == null) { imageFrame = holder.findViewById(AndroidResources.ANDROID_R_ICON_FRAME); } if (imageFrame != null) { if (mIcon != null) { imageFrame.setVisibility(View.VISIBLE); } else { imageFrame.setVisibility(mIconSpaceReserved ? View.INVISIBLE : View.GONE); } } if (mShouldDisableView) { setEnabledStateOnViews(holder.itemView, isEnabled()); } else { setEnabledStateOnViews(holder.itemView, true); } final boolean selectable = isSelectable(); holder.itemView.setFocusable(selectable); holder.itemView.setClickable(selectable); holder.setDividerAllowedAbove(mAllowDividerAbove); holder.setDividerAllowedBelow(mAllowDividerBelow); } /** * Makes sure the view (and any children) get the enabled state changed. */ private void setEnabledStateOnViews(View v, boolean enabled) { v.setEnabled(enabled); if (v instanceof ViewGroup) { final ViewGroup vg = (ViewGroup) v; for (int i = vg.getChildCount() - 1; i >= 0; i--) { setEnabledStateOnViews(vg.getChildAt(i), enabled); } } } /** * Sets the order of this Preference with respect to other * Preference objects on the same level. If this is not specified, the * default behavior is to sort alphabetically. The * {@link PreferenceGroup#setOrderingAsAdded(boolean)} can be used to order * Preference objects based on the order they appear in the XML. * * @param order The order for this Preference. A lower value will be shown * first. Use {@link #DEFAULT_ORDER} to sort alphabetically or * allow ordering from XML. * @see PreferenceGroup#setOrderingAsAdded(boolean) * @see #DEFAULT_ORDER */ public void setOrder(int order) { if (order != mOrder) { mOrder = order; // Reorder the list notifyHierarchyChanged(); } } /** * Gets the order of this Preference with respect to other Preference objects * on the same level. * * @return The order of this Preference. * @see #setOrder(int) */ public int getOrder() { return mOrder; } /** * Set the ID that will be assigned to the overall View representing this * preference, once bound. * * @see View#setId(int) */ public void setViewId(int viewId) { mViewId = viewId; } /** * Sets the title for this Preference with a CharSequence. * This title will be placed into the ID * {@link android.R.id#title} within the View bound by * {@link #onBindViewHolder(PreferenceViewHolder)}. * * @param title The title for this Preference. */ public void setTitle(CharSequence title) { if ((title == null && mTitle != null) || (title != null && !title.equals(mTitle))) { mTitle = title; notifyChanged(); } } /** * Sets the title for this Preference with a resource ID. * * @see #setTitle(CharSequence) * @param titleResId The title as a resource ID. */ public void setTitle(int titleResId) { setTitle(mContext.getString(titleResId)); } /** * Returns the title of this Preference. * * @return The title. * @see #setTitle(CharSequence) */ public CharSequence getTitle() { return mTitle; } /** * Sets the icon for this Preference with a Drawable. * This icon will be placed into the ID * {@link android.R.id#icon} within the View created by * {@link #onBindViewHolder(PreferenceViewHolder)}. * * @param icon The optional icon for this Preference. */ public void setIcon(Drawable icon) { if ((icon == null && mIcon != null) || (icon != null && mIcon != icon)) { mIcon = icon; mIconResId = 0; notifyChanged(); } } /** * Sets the icon for this Preference with a resource ID. * * @see #setIcon(Drawable) * @param iconResId The icon as a resource ID. */ public void setIcon(int iconResId) { setIcon(ContextCompat.getDrawable(mContext, iconResId)); mIconResId = iconResId; } /** * Returns the icon of this Preference. * * @return The icon. * @see #setIcon(Drawable) */ public Drawable getIcon() { if (mIcon == null && mIconResId != 0) { mIcon = ContextCompat.getDrawable(mContext, mIconResId); } return mIcon; } /** * Returns the summary of this Preference. * * @return The summary. * @see #setSummary(CharSequence) */ public CharSequence getSummary() { return mSummary; } /** * Sets the summary for this Preference with a CharSequence. * * @param summary The summary for the preference. */ public void setSummary(CharSequence summary) { if ((summary == null && mSummary != null) || (summary != null && !summary.equals(mSummary))) { mSummary = summary; notifyChanged(); } } /** * Sets the summary for this Preference with a resource ID. * * @see #setSummary(CharSequence) * @param summaryResId The summary as a resource. */ public void setSummary(int summaryResId) { setSummary(mContext.getString(summaryResId)); } /** * Sets whether this Preference is enabled. If disabled, it will * not handle clicks. * * @param enabled Set true to enable it. */ public void setEnabled(boolean enabled) { if (mEnabled != enabled) { mEnabled = enabled; // Enabled state can change dependent preferences' states, so notify notifyDependencyChange(shouldDisableDependents()); notifyChanged(); } } /** * Checks whether this Preference should be enabled in the list. * * @return True if this Preference is enabled, false otherwise. */ public boolean isEnabled() { return mEnabled && mDependencyMet && mParentDependencyMet; } /** * Sets whether this Preference is selectable. * * @param selectable Set true to make it selectable. */ public void setSelectable(boolean selectable) { if (mSelectable != selectable) { mSelectable = selectable; notifyChanged(); } } /** * Checks whether this Preference should be selectable in the list. * * @return True if it is selectable, false otherwise. */ public boolean isSelectable() { return mSelectable; } /** * Sets whether this Preference should disable its view when it gets * disabled. *

* For example, set this and {@link #setEnabled(boolean)} to false for * preferences that are only displaying information and 1) should not be * clickable 2) should not have the view set to the disabled state. * * @param shouldDisableView Set true if this preference should disable its view * when the preference is disabled. */ public void setShouldDisableView(boolean shouldDisableView) { mShouldDisableView = shouldDisableView; notifyChanged(); } /** * Checks whether this Preference should disable its view when it's action is disabled. * @see #setShouldDisableView(boolean) * @return True if it should disable the view. */ public boolean getShouldDisableView() { return mShouldDisableView; } /** * Sets whether this preference should be visible in the list. If false, it is excluded from * the adapter, but can still be retrieved using * {@link PreferenceFragmentCompat#findPreference(CharSequence)}. * * @param visible Set false if this preference should be hidden from the list. * * @attr ref R.styleable#Preference_isPreferenceVisible */ public final void setVisible(boolean visible) { if (mVisible != visible) { mVisible = visible; if (mListener != null) { mListener.onPreferenceVisibilityChange(this); } } } /** * Checks whether this preference should be visible to the user in the list. * @see #setVisible(boolean) * @return True if this preference should be displayed. */ public final boolean isVisible() { return mVisible; } /** * Returns a unique ID for this Preference. This ID should be unique across all * Preference objects in a hierarchy. * * @return A unique ID for this Preference. */ long getId() { return mId; } /** * Processes a click on the preference. This includes saving the value to * the {@link android.content.SharedPreferences}. However, the overridden method should * call {@link #callChangeListener(Object)} to make sure the client wants to * update the preference's state with the new value. */ protected void onClick() { } /** * Sets the key for this Preference, which is used as a key to the {@link SharedPreferences} or * {@link PreferenceDataStore}. This should be unique for the package. * * @param key The key for the preference. */ public void setKey(String key) { mKey = key; if (mRequiresKey && !hasKey()) { requireKey(); } } /** * Gets the key for this Preference, which is also the key used for storing values into * {@link SharedPreferences} or {@link PreferenceDataStore}. * * @return The key. */ public String getKey() { return mKey; } /** * Checks whether the key is present, and if it isn't throws an exception. This should be called * by subclasses that persist their preferences. * * @throws IllegalStateException If there is no key assigned. */ void requireKey() { if (TextUtils.isEmpty(mKey)) { throw new IllegalStateException("Preference does not have a key assigned."); } mRequiresKey = true; } /** * Checks whether this Preference has a valid key. * * @return True if the key exists and is not a blank string, false otherwise. */ public boolean hasKey() { return !TextUtils.isEmpty(mKey); } /** * Checks whether this Preference is persistent. If it is, it stores its value(s) into * the persistent {@link SharedPreferences} storage by default or into * {@link PreferenceDataStore} if assigned. * * @return {@code true} if persistent */ public boolean isPersistent() { return mPersistent; } /** * Checks whether, at the given time this method is called, this Preference should store/restore * its value(s) into the {@link SharedPreferences} or into {@link PreferenceDataStore} if * assigned. This, at minimum, checks whether this Preference is persistent and it currently has * a key. Before you save/restore from the storage, check this first. * * @return {@code true} if it should persist the value */ protected boolean shouldPersist() { return mPreferenceManager != null && isPersistent() && hasKey(); } /** * Sets whether this Preference is persistent. When persistent, it stores its value(s) into * the persistent {@link SharedPreferences} storage by default or into * {@link PreferenceDataStore} if assigned. * * @param persistent set {@code true} if it should store its value(s) into the storage. */ public void setPersistent(boolean persistent) { mPersistent = persistent; } /** * Sets whether to constrain the title of this Preference to a single line instead of * letting it wrap onto multiple lines. * * @param singleLineTitle set {@code true} if the title should be constrained to one line * * @attr ref R.styleable#Preference_android_singleLineTitle */ public void setSingleLineTitle(boolean singleLineTitle) { mHasSingleLineTitleAttr = true; mSingleLineTitle = singleLineTitle; } /** * Gets whether the title of this preference is constrained to a single line. * * @see #setSingleLineTitle(boolean) * @return {@code true} if the title of this preference is constrained to a single line * * @attr ref R.styleable#Preference_android_singleLineTitle */ public boolean isSingleLineTitle() { return mSingleLineTitle; } /** * Sets whether to reserve the space of this Preference icon view when no icon is provided. If * set to true, the preference will be offset as if it would have the icon and thus aligned with * other preferences having icons. * * @param iconSpaceReserved set {@code true} if the space for the icon view should be reserved * * @attr ref R.styleable#Preference_android_iconSpaceReserved */ public void setIconSpaceReserved(boolean iconSpaceReserved) { mIconSpaceReserved = iconSpaceReserved; notifyChanged(); } /** * Returns whether the space of this preference icon view is reserved. * * @see #setIconSpaceReserved(boolean) * @return {@code true} if the space of this preference icon view is reserved * * @attr ref R.styleable#Preference_android_iconSpaceReserved */ public boolean isIconSpaceReserved() { return mIconSpaceReserved; } /** * Call this method after the user changes the preference, but before the * internal state is set. This allows the client to ignore the user value. * * @param newValue The new value of this Preference. * @return True if the user value should be set as the preference * value (and persisted). */ public boolean callChangeListener(Object newValue) { return mOnChangeListener == null || mOnChangeListener.onPreferenceChange(this, newValue); } /** * Sets the callback to be invoked when this Preference is changed by the * user (but before the internal state has been updated). * * @param onPreferenceChangeListener The callback to be invoked. */ public void setOnPreferenceChangeListener( OnPreferenceChangeListener onPreferenceChangeListener) { mOnChangeListener = onPreferenceChangeListener; } /** * Returns the callback to be invoked when this Preference is changed by the * user (but before the internal state has been updated). * * @return The callback to be invoked. */ public OnPreferenceChangeListener getOnPreferenceChangeListener() { return mOnChangeListener; } /** * Sets the callback to be invoked when this Preference is clicked. * * @param onPreferenceClickListener The callback to be invoked. */ public void setOnPreferenceClickListener(OnPreferenceClickListener onPreferenceClickListener) { mOnClickListener = onPreferenceClickListener; } /** * Returns the callback to be invoked when this Preference is clicked. * * @return The callback to be invoked. */ public OnPreferenceClickListener getOnPreferenceClickListener() { return mOnClickListener; } /** * @hide */ @RestrictTo(LIBRARY_GROUP) protected void performClick(View view) { performClick(); } /** * Called when a click should be performed. * * @hide */ @RestrictTo(LIBRARY_GROUP) public void performClick() { if (!isEnabled()) { return; } onClick(); if (mOnClickListener != null && mOnClickListener.onPreferenceClick(this)) { return; } PreferenceManager preferenceManager = getPreferenceManager(); if (preferenceManager != null) { PreferenceManager.OnPreferenceTreeClickListener listener = preferenceManager .getOnPreferenceTreeClickListener(); if (listener != null && listener.onPreferenceTreeClick(this)) { return; } } if (mIntent != null) { Context context = getContext(); context.startActivity(mIntent); } } /** * Returns the {@link android.content.Context} of this Preference. * Each Preference in a Preference hierarchy can be * from different Context (for example, if multiple activities provide preferences into a single * {@link PreferenceFragmentCompat}). This Context will be used to save the Preference values. * * @return The Context of this Preference. */ public Context getContext() { return mContext; } /** * Returns the {@link android.content.SharedPreferences} where this Preference can read its * value(s). Usually, it's easier to use one of the helper read methods: * {@link #getPersistedBoolean(boolean)}, {@link #getPersistedFloat(float)}, * {@link #getPersistedInt(int)}, {@link #getPersistedLong(long)}, * {@link #getPersistedString(String)}. * * @return the {@link SharedPreferences} where this Preference reads its value(s). If this * preference is not attached to a Preference hierarchy or if a * {@link PreferenceDataStore} has been set, this method returns {@code null}. * @see #setPreferenceDataStore(PreferenceDataStore) */ public SharedPreferences getSharedPreferences() { if (mPreferenceManager == null || getPreferenceDataStore() != null) { return null; } return mPreferenceManager.getSharedPreferences(); } /** * Compares Preference objects based on order (if set), otherwise alphabetically on the titles. * * @param another The Preference to compare to this one. * @return 0 if the same; less than 0 if this Preference sorts ahead of another; * greater than 0 if this Preference sorts after another. */ @Override public int compareTo(@NonNull Preference another) { if (mOrder != another.mOrder) { // Do order comparison return mOrder - another.mOrder; } else if (mTitle == another.mTitle) { // If titles are null or share same object comparison return 0; } else if (mTitle == null) { return 1; } else if (another.mTitle == null) { return -1; } else { // Do name comparison return mTitle.toString().compareToIgnoreCase(another.mTitle.toString()); } } /** * Sets the internal change listener. * * @param listener The listener. * @see #notifyChanged() */ final void setOnPreferenceChangeInternalListener(OnPreferenceChangeInternalListener listener) { mListener = listener; } /** * Should be called when the data of this {@link Preference} has changed. */ protected void notifyChanged() { if (mListener != null) { mListener.onPreferenceChange(this); } } /** * Should be called when a Preference has been * added/removed from this group, or the ordering should be * re-evaluated. */ protected void notifyHierarchyChanged() { if (mListener != null) { mListener.onPreferenceHierarchyChange(this); } } /** * Gets the {@link PreferenceManager} that manages this Preference object's tree. * * @return The {@link PreferenceManager}. */ public PreferenceManager getPreferenceManager() { return mPreferenceManager; } /** * Called when this Preference has been attached to a Preference hierarchy. * Make sure to call the super implementation. * * @param preferenceManager The PreferenceManager of the hierarchy. */ protected void onAttachedToHierarchy(PreferenceManager preferenceManager) { mPreferenceManager = preferenceManager; if (!mHasId) { mId = preferenceManager.getNextId(); } dispatchSetInitialValue(); } /** * Called from {@link PreferenceGroup} to pass in an ID for reuse * @hide */ @RestrictTo(LIBRARY_GROUP) protected void onAttachedToHierarchy(PreferenceManager preferenceManager, long id) { mId = id; mHasId = true; try { onAttachedToHierarchy(preferenceManager); } finally { mHasId = false; } } /** * Assigns a {@link PreferenceGroup} as the parent of this Preference. Set null to remove * the current parent. * * @param parentGroup Parent preference group of this Preference or null if none. */ void assignParent(@Nullable PreferenceGroup parentGroup) { mParentGroup = parentGroup; } /** * Called when the Preference hierarchy has been attached to the * list of preferences. This can also be called when this * Preference has been attached to a group that was already attached * to the list of preferences. */ public void onAttached() { // At this point, the hierarchy that this preference is in is connected // with all other preferences. registerDependency(); } /** * Called when the Preference hierarchy has been detached from the * list of preferences. This can also be called when this * Preference has been removed from a group that was attached * to the list of preferences. */ public void onDetached() { unregisterDependency(); mWasDetached = true; } /** * Returns true if {@link #onDetached()} was called. Used for handling the case when a * preference was removed, modified, and re-added to a {@link PreferenceGroup} * @hide */ @RestrictTo(LIBRARY) public final boolean wasDetached() { return mWasDetached; } /** * Clears the {@link #wasDetached()} status * @hide */ @RestrictTo(LIBRARY) public final void clearWasDetached() { mWasDetached = false; } private void registerDependency() { if (TextUtils.isEmpty(mDependencyKey)) return; Preference preference = findPreferenceInHierarchy(mDependencyKey); if (preference != null) { preference.registerDependent(this); } else { throw new IllegalStateException("Dependency \"" + mDependencyKey + "\" not found for preference \"" + mKey + "\" (title: \"" + mTitle + "\""); } } private void unregisterDependency() { if (mDependencyKey != null) { final Preference oldDependency = findPreferenceInHierarchy(mDependencyKey); if (oldDependency != null) { oldDependency.unregisterDependent(this); } } } /** * Finds a Preference in this hierarchy (the whole thing, * even above/below your {@link PreferenceScreen} screen break) with the given * key. *

* This only functions after we have been attached to a hierarchy. * * @param key The key of the Preference to find. * @return The Preference that uses the given key. */ protected Preference findPreferenceInHierarchy(String key) { if (TextUtils.isEmpty(key) || mPreferenceManager == null) { return null; } return mPreferenceManager.findPreference(key); } /** * Adds a dependent Preference on this Preference so we can notify it. * Usually, the dependent Preference registers itself (it's good for it to * know it depends on something), so please use * {@link Preference#setDependency(String)} on the dependent Preference. * * @param dependent The dependent Preference that will be enabled/disabled * according to the state of this Preference. */ private void registerDependent(Preference dependent) { if (mDependents == null) { mDependents = new ArrayList(); } mDependents.add(dependent); dependent.onDependencyChanged(this, shouldDisableDependents()); } /** * Removes a dependent Preference on this Preference. * * @param dependent The dependent Preference that will be enabled/disabled * according to the state of this Preference. */ private void unregisterDependent(Preference dependent) { if (mDependents != null) { mDependents.remove(dependent); } } /** * Notifies any listening dependents of a change that affects the * dependency. * * @param disableDependents Whether this Preference should disable * its dependents. */ public void notifyDependencyChange(boolean disableDependents) { final List dependents = mDependents; if (dependents == null) { return; } final int dependentsCount = dependents.size(); for (int i = 0; i < dependentsCount; i++) { dependents.get(i).onDependencyChanged(this, disableDependents); } } /** * Called when the dependency changes. * * @param dependency The Preference that this Preference depends on. * @param disableDependent Set true to disable this Preference. */ public void onDependencyChanged(Preference dependency, boolean disableDependent) { if (mDependencyMet == disableDependent) { mDependencyMet = !disableDependent; // Enabled state can change dependent preferences' states, so notify notifyDependencyChange(shouldDisableDependents()); notifyChanged(); } } /** * Called when the implicit parent dependency changes. * * @param parent The Preference that this Preference depends on. * @param disableChild Set true to disable this Preference. */ public void onParentChanged(Preference parent, boolean disableChild) { if (mParentDependencyMet == disableChild) { mParentDependencyMet = !disableChild; // Enabled state can change dependent preferences' states, so notify notifyDependencyChange(shouldDisableDependents()); notifyChanged(); } } /** * Checks whether this preference's dependents should currently be * disabled. * * @return True if the dependents should be disabled, otherwise false. */ public boolean shouldDisableDependents() { return !isEnabled(); } /** * Sets the key of a Preference that this Preference will depend on. If that * Preference is not set or is off, this Preference will be disabled. * * @param dependencyKey The key of the Preference that this depends on. */ public void setDependency(String dependencyKey) { // Unregister the old dependency, if we had one unregisterDependency(); // Register the new mDependencyKey = dependencyKey; registerDependency(); } /** * Returns the key of the dependency on this Preference. * * @return The key of the dependency. * @see #setDependency(String) */ public String getDependency() { return mDependencyKey; } /** * Returns the {@link PreferenceGroup} which is this Preference assigned to or null if this * preference is not assigned to any group or is a root Preference. * * @return The parent PreferenceGroup or null if not attached to any. */ @Nullable public PreferenceGroup getParent() { return mParentGroup; } /** * Called when this Preference is being removed from the hierarchy. You * should remove any references to this Preference that you know about. Make * sure to call through to the superclass implementation. */ protected void onPrepareForRemoval() { unregisterDependency(); } /** * Sets the default value for this Preference, which will be set either if * persistence is off or persistence is on and the preference is not found * in the persistent storage. * * @param defaultValue The default value. */ public void setDefaultValue(Object defaultValue) { mDefaultValue = defaultValue; } private void dispatchSetInitialValue() { if (getPreferenceDataStore() != null) { onSetInitialValue(true, mDefaultValue); return; } // By now, we know if we are persistent. final boolean shouldPersist = shouldPersist(); if (!shouldPersist || !getSharedPreferences().contains(mKey)) { if (mDefaultValue != null) { onSetInitialValue(false, mDefaultValue); } } else { onSetInitialValue(true, null); } } /** * Implement this to set the initial value of the Preference. * *

If restorePersistedValue is true, you should restore the * Preference value from the {@link android.content.SharedPreferences}. If * restorePersistedValue is false, you should set the Preference * value to defaultValue that is given (and possibly store to SharedPreferences * if {@link #shouldPersist()} is true). * *

In case of using {@link PreferenceDataStore}, the restorePersistedValue is * always {@code true} but the default value (if provided) is set. * *

This may not always be called. One example is if it should not persist * but there is no default value given. * * @param restorePersistedValue True to restore the persisted value; * false to use the given defaultValue. * @param defaultValue The default value for this Preference. Only use this * if restorePersistedValue is false. */ protected void onSetInitialValue(boolean restorePersistedValue, Object defaultValue) { } private void tryCommit(@NonNull SharedPreferences.Editor editor) { if (mPreferenceManager.shouldCommit()) { editor.apply(); } } /** * Attempts to persist a {@link String} if this Preference is persistent. * *

The returned value doesn't reflect whether the given value was persisted, since we may not * necessarily commit if there will be a batch commit later. * * @param value The value to persist. * @return {@code true} if the Preference is persistent, {@code false} otherwise * @see #getPersistedString(String) */ protected boolean persistString(String value) { if (!shouldPersist()) { return false; } // Shouldn't store null if (TextUtils.equals(value, getPersistedString(null))) { // It's already there, so the same as persisting return true; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { dataStore.putString(mKey, value); } else { SharedPreferences.Editor editor = mPreferenceManager.getEditor(); editor.putString(mKey, value); tryCommit(editor); } return true; } /** * Attempts to get a persisted set of Strings if this Preference is persistent. * * @param defaultReturnValue The default value to return if either the * Preference is not persistent or the Preference is not in the * shared preferences. * @return the value from the storage or the default return value * @see #persistString(String) */ protected String getPersistedString(String defaultReturnValue) { if (!shouldPersist()) { return defaultReturnValue; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { return dataStore.getString(mKey, defaultReturnValue); } return mPreferenceManager.getSharedPreferences().getString(mKey, defaultReturnValue); } /** * Attempts to persist a set of Strings if this Preference is persistent. * *

The returned value doesn't reflect whether the given value was persisted, since we may not * necessarily commit if there will be a batch commit later. * * @param values the values to persist * @return {@code true} if the Preference is persistent, {@code false} otherwise * @see #getPersistedStringSet(Set) */ public boolean persistStringSet(Set values) { if (!shouldPersist()) { return false; } // Shouldn't store null if (values.equals(getPersistedStringSet(null))) { // It's already there, so the same as persisting return true; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { dataStore.putStringSet(mKey, values); } else { SharedPreferences.Editor editor = mPreferenceManager.getEditor(); editor.putStringSet(mKey, values); tryCommit(editor); } return true; } /** * Attempts to get a persisted set of Strings if this Preference is persistent. * * @param defaultReturnValue the default value to return if either this Preference is not * persistent or this Preference is not present * @return the value from the storage or the default return value * @see #persistStringSet(Set) */ public Set getPersistedStringSet(Set defaultReturnValue) { if (!shouldPersist()) { return defaultReturnValue; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { return dataStore.getStringSet(mKey, defaultReturnValue); } return mPreferenceManager.getSharedPreferences().getStringSet(mKey, defaultReturnValue); } /** * Attempts to persist an {@link Integer} if this Preference is persistent. * *

The returned value doesn't reflect whether the given value was persisted, since we may not * necessarily commit if there will be a batch commit later. * * @param value The value to persist. * @return {@code true} if the Preference is persistent, {@code false} otherwise * @see #persistString(String) * @see #getPersistedInt(int) */ protected boolean persistInt(int value) { if (!shouldPersist()) { return false; } if (value == getPersistedInt(~value)) { // It's already there, so the same as persisting return true; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { dataStore.putInt(mKey, value); } else { SharedPreferences.Editor editor = mPreferenceManager.getEditor(); editor.putInt(mKey, value); tryCommit(editor); } return true; } /** * Attempts to get a persisted {@link Integer} if this Preference is persistent. * * @param defaultReturnValue The default value to return if either this * Preference is not persistent or this Preference is not in the * SharedPreferences. * @return the value from the storage or the default return value * @see #getPersistedString(String) * @see #persistInt(int) */ protected int getPersistedInt(int defaultReturnValue) { if (!shouldPersist()) { return defaultReturnValue; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { return dataStore.getInt(mKey, defaultReturnValue); } return mPreferenceManager.getSharedPreferences().getInt(mKey, defaultReturnValue); } /** * Attempts to persist a {@link Float} if this Preference is persistent. * *

The returned value doesn't reflect whether the given value was persisted, since we may not * necessarily commit if there will be a batch commit later. * * @param value The value to persist. * @return {@code true} if the Preference is persistent, {@code false} otherwise * @see #persistString(String) * @see #getPersistedFloat(float) */ protected boolean persistFloat(float value) { if (!shouldPersist()) { return false; } if (value == getPersistedFloat(Float.NaN)) { // It's already there, so the same as persisting return true; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { dataStore.putFloat(mKey, value); } else { SharedPreferences.Editor editor = mPreferenceManager.getEditor(); editor.putFloat(mKey, value); tryCommit(editor); } return true; } /** * Attempts to get a persisted {@link Float} if this Preference is persistent. * * @param defaultReturnValue The default value to return if either this * Preference is not persistent or this Preference is not in the * SharedPreferences. * @return the value from the storage or the default return value * @see #getPersistedString(String) * @see #persistFloat(float) */ protected float getPersistedFloat(float defaultReturnValue) { if (!shouldPersist()) { return defaultReturnValue; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { return dataStore.getFloat(mKey, defaultReturnValue); } return mPreferenceManager.getSharedPreferences().getFloat(mKey, defaultReturnValue); } /** * Attempts to persist a {@link Long} if this Preference is persistent. * *

The returned value doesn't reflect whether the given value was persisted, since we may not * necessarily commit if there will be a batch commit later. * * @param value The value to persist. * @return {@code true} if the Preference is persistent, {@code false} otherwise * @see #persistString(String) * @see #getPersistedLong(long) */ protected boolean persistLong(long value) { if (!shouldPersist()) { return false; } if (value == getPersistedLong(~value)) { // It's already there, so the same as persisting return true; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { dataStore.putLong(mKey, value); } else { SharedPreferences.Editor editor = mPreferenceManager.getEditor(); editor.putLong(mKey, value); tryCommit(editor); } return true; } /** * Attempts to get a persisted {@link Long} if this Preference is persistent. * * @param defaultReturnValue The default value to return if either this * Preference is not persistent or this Preference is not in the * SharedPreferences. * @return the value from the storage or the default return value * @see #getPersistedString(String) * @see #persistLong(long) */ protected long getPersistedLong(long defaultReturnValue) { if (!shouldPersist()) { return defaultReturnValue; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { return dataStore.getLong(mKey, defaultReturnValue); } return mPreferenceManager.getSharedPreferences().getLong(mKey, defaultReturnValue); } /** * Attempts to persist a {@link Boolean} if this Preference is persistent. * *

The returned value doesn't reflect whether the given value was persisted, since we may not * necessarily commit if there will be a batch commit later. * * @param value The value to persist. * @return {@code true} if the Preference is persistent, {@code false} otherwise * @see #persistString(String) * @see #getPersistedBoolean(boolean) */ protected boolean persistBoolean(boolean value) { if (!shouldPersist()) { return false; } if (value == getPersistedBoolean(!value)) { // It's already there, so the same as persisting return true; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { dataStore.putBoolean(mKey, value); } else { SharedPreferences.Editor editor = mPreferenceManager.getEditor(); editor.putBoolean(mKey, value); tryCommit(editor); } return true; } /** * Attempts to get a persisted {@link Boolean} if this Preference is persistent. * * @param defaultReturnValue The default value to return if either this * Preference is not persistent or this Preference is not in the * SharedPreferences. * @return the value from the storage or the default return value * @see #getPersistedString(String) * @see #persistBoolean(boolean) */ protected boolean getPersistedBoolean(boolean defaultReturnValue) { if (!shouldPersist()) { return defaultReturnValue; } PreferenceDataStore dataStore = getPreferenceDataStore(); if (dataStore != null) { return dataStore.getBoolean(mKey, defaultReturnValue); } return mPreferenceManager.getSharedPreferences().getBoolean(mKey, defaultReturnValue); } @Override public String toString() { return getFilterableStringBuilder().toString(); } /** * Returns the text that will be used to filter this Preference depending on * user input. *

* If overriding and calling through to the superclass, make sure to prepend * your additions with a space. * * @return Text as a {@link StringBuilder} that will be used to filter this * preference. By default, this is the title and summary * (concatenated with a space). */ StringBuilder getFilterableStringBuilder() { StringBuilder sb = new StringBuilder(); CharSequence title = getTitle(); if (!TextUtils.isEmpty(title)) { sb.append(title).append(' '); } CharSequence summary = getSummary(); if (!TextUtils.isEmpty(summary)) { sb.append(summary).append(' '); } if (sb.length() > 0) { // Drop the last space sb.setLength(sb.length() - 1); } return sb; } /** * Store this Preference hierarchy's frozen state into the given container. * * @param container The Bundle in which to save the instance of this Preference. * * @see #restoreHierarchyState * @see #onSaveInstanceState */ public void saveHierarchyState(Bundle container) { dispatchSaveInstanceState(container); } /** * Called by {@link #saveHierarchyState} to store the instance for this Preference and its * children. May be overridden to modify how the save happens for children. For example, some * Preference objects may want to not store an instance for their children. * * @param container The Bundle in which to save the instance of this Preference. * * @see #saveHierarchyState * @see #onSaveInstanceState */ void dispatchSaveInstanceState(Bundle container) { if (hasKey()) { mBaseMethodCalled = false; Parcelable state = onSaveInstanceState(); if (!mBaseMethodCalled) { throw new IllegalStateException( "Derived class did not call super.onSaveInstanceState()"); } if (state != null) { container.putParcelable(mKey, state); } } } /** * Hook allowing a Preference to generate a representation of its internal * state that can later be used to create a new instance with that same * state. This state should only contain information that is not persistent * or can be reconstructed later. * * @return A Parcelable object containing the current dynamic state of * this Preference, or null if there is nothing interesting to save. * The default implementation returns null. * @see #onRestoreInstanceState * @see #saveHierarchyState */ protected Parcelable onSaveInstanceState() { mBaseMethodCalled = true; return BaseSavedState.EMPTY_STATE; } /** * Restore this Preference hierarchy's previously saved state from the given container. * * @param container The Bundle that holds the previously saved state. * * @see #saveHierarchyState * @see #onRestoreInstanceState */ public void restoreHierarchyState(Bundle container) { dispatchRestoreInstanceState(container); } /** * Called by {@link #restoreHierarchyState} to retrieve the saved state for this * Preference and its children. May be overridden to modify how restoring * happens to the children of a Preference. For example, some Preference objects may * not want to save state for their children. * * @param container The Bundle that holds the previously saved state. * @see #restoreHierarchyState * @see #onRestoreInstanceState */ void dispatchRestoreInstanceState(Bundle container) { if (hasKey()) { Parcelable state = container.getParcelable(mKey); if (state != null) { mBaseMethodCalled = false; onRestoreInstanceState(state); if (!mBaseMethodCalled) { throw new IllegalStateException( "Derived class did not call super.onRestoreInstanceState()"); } } } } /** * Hook allowing a Preference to re-apply a representation of its internal * state that had previously been generated by {@link #onSaveInstanceState}. * This function will never be called with a null state. * * @param state The saved state that had previously been returned by * {@link #onSaveInstanceState}. * @see #onSaveInstanceState * @see #restoreHierarchyState */ protected void onRestoreInstanceState(Parcelable state) { mBaseMethodCalled = true; if (state != BaseSavedState.EMPTY_STATE && state != null) { throw new IllegalArgumentException("Wrong state class -- expecting Preference State"); } } /** * Initializes an {@link android.view.accessibility.AccessibilityNodeInfo} with information * about the View for this Preference. */ @CallSuper public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfoCompat info) { } /** * A base class for managing the instance state of a {@link Preference}. */ public static class BaseSavedState extends AbsSavedState { public BaseSavedState(Parcel source) { super(source); } public BaseSavedState(Parcelable superState) { super(superState); } public static final Parcelable.Creator CREATOR = new Parcelable.Creator() { @Override public BaseSavedState createFromParcel(Parcel in) { return new BaseSavedState(in); } @Override public BaseSavedState[] newArray(int size) { return new BaseSavedState[size]; } }; } }





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