com.actionbarsherlock.view.MenuInflater Maven / Gradle / Ivy
/*
* Copyright (C) 2006 The Android Open Source Project
* 2011 Jake Wharton
*
* 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 com.actionbarsherlock.view;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import android.content.Context;
import android.content.res.TypedArray;
import android.content.res.XmlResourceParser;
import android.util.AttributeSet;
import android.util.Log;
import android.util.TypedValue;
import android.util.Xml;
import android.view.InflateException;
import android.view.View;
import com.actionbarsherlock.R;
import com.actionbarsherlock.internal.view.menu.MenuItemImpl;
/**
* This class is used to instantiate menu XML files into Menu objects.
*
* For performance reasons, menu inflation relies heavily on pre-processing of
* XML files that is done at build time. Therefore, it is not currently possible
* to use MenuInflater with an XmlPullParser over a plain XML file at runtime;
* it only works with an XmlPullParser returned from a compiled resource (R.
* something file.)
*/
public class MenuInflater {
private static final String LOG_TAG = "MenuInflater";
/** Menu tag name in XML. */
private static final String XML_MENU = "menu";
/** Group tag name in XML. */
private static final String XML_GROUP = "group";
/** Item tag name in XML. */
private static final String XML_ITEM = "item";
private static final int NO_ID = 0;
private static final Class[] ACTION_VIEW_CONSTRUCTOR_SIGNATURE = new Class[] {Context.class};
private static final Class[] ACTION_PROVIDER_CONSTRUCTOR_SIGNATURE = ACTION_VIEW_CONSTRUCTOR_SIGNATURE;
private final Object[] mActionViewConstructorArguments;
private final Object[] mActionProviderConstructorArguments;
private Context mContext;
/**
* Constructs a menu inflater.
*
* @see Activity#getMenuInflater()
*/
public MenuInflater(Context context) {
mContext = context;
mActionViewConstructorArguments = new Object[] {context};
mActionProviderConstructorArguments = mActionViewConstructorArguments;
}
/**
* Inflate a menu hierarchy from the specified XML resource. Throws
* {@link InflateException} if there is an error.
*
* @param menuRes Resource ID for an XML layout resource to load (e.g.,
* R.menu.main_activity)
* @param menu The Menu to inflate into. The items and submenus will be
* added to this Menu.
*/
public void inflate(int menuRes, Menu menu) {
XmlResourceParser parser = null;
try {
parser = mContext.getResources().getLayout(menuRes);
AttributeSet attrs = Xml.asAttributeSet(parser);
parseMenu(parser, attrs, menu);
} catch (XmlPullParserException e) {
throw new InflateException("Error inflating menu XML", e);
} catch (IOException e) {
throw new InflateException("Error inflating menu XML", e);
} finally {
if (parser != null) parser.close();
}
}
/**
* Called internally to fill the given menu. If a sub menu is seen, it will
* call this recursively.
*/
private void parseMenu(XmlPullParser parser, AttributeSet attrs, Menu menu)
throws XmlPullParserException, IOException {
MenuState menuState = new MenuState(menu);
int eventType = parser.getEventType();
String tagName;
boolean lookingForEndOfUnknownTag = false;
String unknownTagName = null;
// This loop will skip to the menu start tag
do {
if (eventType == XmlPullParser.START_TAG) {
tagName = parser.getName();
if (tagName.equals(XML_MENU)) {
// Go to next tag
eventType = parser.next();
break;
}
throw new RuntimeException("Expecting menu, got " + tagName);
}
eventType = parser.next();
} while (eventType != XmlPullParser.END_DOCUMENT);
boolean reachedEndOfMenu = false;
while (!reachedEndOfMenu) {
switch (eventType) {
case XmlPullParser.START_TAG:
if (lookingForEndOfUnknownTag) {
break;
}
tagName = parser.getName();
if (tagName.equals(XML_GROUP)) {
menuState.readGroup(attrs);
} else if (tagName.equals(XML_ITEM)) {
menuState.readItem(attrs);
} else if (tagName.equals(XML_MENU)) {
// A menu start tag denotes a submenu for an item
SubMenu subMenu = menuState.addSubMenuItem();
// Parse the submenu into returned SubMenu
parseMenu(parser, attrs, subMenu);
} else {
lookingForEndOfUnknownTag = true;
unknownTagName = tagName;
}
break;
case XmlPullParser.END_TAG:
tagName = parser.getName();
if (lookingForEndOfUnknownTag && tagName.equals(unknownTagName)) {
lookingForEndOfUnknownTag = false;
unknownTagName = null;
} else if (tagName.equals(XML_GROUP)) {
menuState.resetGroup();
} else if (tagName.equals(XML_ITEM)) {
// Add the item if it hasn't been added (if the item was
// a submenu, it would have been added already)
if (!menuState.hasAddedItem()) {
if (menuState.itemActionProvider != null &&
menuState.itemActionProvider.hasSubMenu()) {
menuState.addSubMenuItem();
} else {
menuState.addItem();
}
}
} else if (tagName.equals(XML_MENU)) {
reachedEndOfMenu = true;
}
break;
case XmlPullParser.END_DOCUMENT:
throw new RuntimeException("Unexpected end of document");
}
eventType = parser.next();
}
}
private static class InflatedOnMenuItemClickListener
implements MenuItem.OnMenuItemClickListener {
private static final Class[] PARAM_TYPES = new Class[] { MenuItem.class };
private Context mContext;
private Method mMethod;
public InflatedOnMenuItemClickListener(Context context, String methodName) {
mContext = context;
Class c = context.getClass();
try {
mMethod = c.getMethod(methodName, PARAM_TYPES);
} catch (Exception e) {
InflateException ex = new InflateException(
"Couldn't resolve menu item onClick handler " + methodName +
" in class " + c.getName());
ex.initCause(e);
throw ex;
}
}
public boolean onMenuItemClick(MenuItem item) {
try {
if (mMethod.getReturnType() == Boolean.TYPE) {
return (Boolean) mMethod.invoke(mContext, item);
} else {
mMethod.invoke(mContext, item);
return true;
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
/**
* State for the current menu.
*
* Groups can not be nested unless there is another menu (which will have
* its state class).
*/
private class MenuState {
private Menu menu;
/*
* Group state is set on items as they are added, allowing an item to
* override its group state. (As opposed to set on items at the group end tag.)
*/
private int groupId;
private int groupCategory;
private int groupOrder;
private int groupCheckable;
private boolean groupVisible;
private boolean groupEnabled;
private boolean itemAdded;
private int itemId;
private int itemCategoryOrder;
private CharSequence itemTitle;
private CharSequence itemTitleCondensed;
private int itemIconResId;
private char itemAlphabeticShortcut;
private char itemNumericShortcut;
/**
* Sync to attrs.xml enum:
* - 0: none
* - 1: all
* - 2: exclusive
*/
private int itemCheckable;
private boolean itemChecked;
private boolean itemVisible;
private boolean itemEnabled;
/**
* Sync to attrs.xml enum, values in MenuItem:
* - 0: never
* - 1: ifRoom
* - 2: always
* - -1: Safe sentinel for "no value".
*/
private int itemShowAsAction;
private int itemActionViewLayout;
private String itemActionViewClassName;
private String itemActionProviderClassName;
private String itemListenerMethodName;
private ActionProvider itemActionProvider;
private static final int defaultGroupId = NO_ID;
private static final int defaultItemId = NO_ID;
private static final int defaultItemCategory = 0;
private static final int defaultItemOrder = 0;
private static final int defaultItemCheckable = 0;
private static final boolean defaultItemChecked = false;
private static final boolean defaultItemVisible = true;
private static final boolean defaultItemEnabled = true;
public MenuState(final Menu menu) {
this.menu = menu;
resetGroup();
}
public void resetGroup() {
groupId = defaultGroupId;
groupCategory = defaultItemCategory;
groupOrder = defaultItemOrder;
groupCheckable = defaultItemCheckable;
groupVisible = defaultItemVisible;
groupEnabled = defaultItemEnabled;
}
/**
* Called when the parser is pointing to a group tag.
*/
public void readGroup(AttributeSet attrs) {
TypedArray a = mContext.obtainStyledAttributes(attrs,
R.styleable.SherlockMenuGroup);
groupId = a.getResourceId(R.styleable.SherlockMenuGroup_android_id, defaultGroupId);
groupCategory = a.getInt(R.styleable.SherlockMenuGroup_android_menuCategory, defaultItemCategory);
groupOrder = a.getInt(R.styleable.SherlockMenuGroup_android_orderInCategory, defaultItemOrder);
groupCheckable = a.getInt(R.styleable.SherlockMenuGroup_android_checkableBehavior, defaultItemCheckable);
groupVisible = a.getBoolean(R.styleable.SherlockMenuGroup_android_visible, defaultItemVisible);
groupEnabled = a.getBoolean(R.styleable.SherlockMenuGroup_android_enabled, defaultItemEnabled);
a.recycle();
}
/**
* Called when the parser is pointing to an item tag.
*/
public void readItem(AttributeSet attrs) {
TypedArray a = mContext.obtainStyledAttributes(attrs,
R.styleable.SherlockMenuItem);
// Inherit attributes from the group as default value
itemId = a.getResourceId(R.styleable.SherlockMenuItem_android_id, defaultItemId);
final int category = a.getInt(R.styleable.SherlockMenuItem_android_menuCategory, groupCategory);
final int order = a.getInt(R.styleable.SherlockMenuItem_android_orderInCategory, groupOrder);
itemCategoryOrder = (category & Menu.CATEGORY_MASK) | (order & Menu.USER_MASK);
itemTitle = a.getText(R.styleable.SherlockMenuItem_android_title);
itemTitleCondensed = a.getText(R.styleable.SherlockMenuItem_android_titleCondensed);
itemIconResId = a.getResourceId(R.styleable.SherlockMenuItem_android_icon, 0);
itemAlphabeticShortcut =
getShortcut(a.getString(R.styleable.SherlockMenuItem_android_alphabeticShortcut));
itemNumericShortcut =
getShortcut(a.getString(R.styleable.SherlockMenuItem_android_numericShortcut));
if (a.hasValue(R.styleable.SherlockMenuItem_android_checkable)) {
// Item has attribute checkable, use it
itemCheckable = a.getBoolean(R.styleable.SherlockMenuItem_android_checkable, false) ? 1 : 0;
} else {
// Item does not have attribute, use the group's (group can have one more state
// for checkable that represents the exclusive checkable)
itemCheckable = groupCheckable;
}
itemChecked = a.getBoolean(R.styleable.SherlockMenuItem_android_checked, defaultItemChecked);
itemVisible = a.getBoolean(R.styleable.SherlockMenuItem_android_visible, groupVisible);
itemEnabled = a.getBoolean(R.styleable.SherlockMenuItem_android_enabled, groupEnabled);
TypedValue value = new TypedValue();
a.getValue(R.styleable.SherlockMenuItem_android_showAsAction, value);
itemShowAsAction = value.type == TypedValue.TYPE_INT_HEX ? value.data : -1;
itemListenerMethodName = a.getString(R.styleable.SherlockMenuItem_android_onClick);
itemActionViewLayout = a.getResourceId(R.styleable.SherlockMenuItem_android_actionLayout, 0);
itemActionViewClassName = a.getString(R.styleable.SherlockMenuItem_android_actionViewClass);
itemActionProviderClassName = a.getString(R.styleable.SherlockMenuItem_android_actionProviderClass);
final boolean hasActionProvider = itemActionProviderClassName != null;
if (hasActionProvider && itemActionViewLayout == 0 && itemActionViewClassName == null) {
itemActionProvider = newInstance(itemActionProviderClassName,
ACTION_PROVIDER_CONSTRUCTOR_SIGNATURE,
mActionProviderConstructorArguments);
} else {
if (hasActionProvider) {
Log.w(LOG_TAG, "Ignoring attribute 'actionProviderClass'."
+ " Action view already specified.");
}
itemActionProvider = null;
}
a.recycle();
itemAdded = false;
}
private char getShortcut(String shortcutString) {
if (shortcutString == null) {
return 0;
} else {
return shortcutString.charAt(0);
}
}
private void setItem(MenuItem item) {
item.setChecked(itemChecked)
.setVisible(itemVisible)
.setEnabled(itemEnabled)
.setCheckable(itemCheckable >= 1)
.setTitleCondensed(itemTitleCondensed)
.setIcon(itemIconResId)
.setAlphabeticShortcut(itemAlphabeticShortcut)
.setNumericShortcut(itemNumericShortcut);
if (itemShowAsAction >= 0) {
item.setShowAsAction(itemShowAsAction);
}
if (itemListenerMethodName != null) {
if (mContext.isRestricted()) {
throw new IllegalStateException("The android:onClick attribute cannot "
+ "be used within a restricted context");
}
item.setOnMenuItemClickListener(
new InflatedOnMenuItemClickListener(mContext, itemListenerMethodName));
}
if (itemCheckable >= 2) {
if (item instanceof MenuItemImpl) {
MenuItemImpl impl = (MenuItemImpl) item;
impl.setExclusiveCheckable(true);
} else {
menu.setGroupCheckable(groupId, true, true);
}
}
boolean actionViewSpecified = false;
if (itemActionViewClassName != null) {
View actionView = (View) newInstance(itemActionViewClassName,
ACTION_VIEW_CONSTRUCTOR_SIGNATURE, mActionViewConstructorArguments);
item.setActionView(actionView);
actionViewSpecified = true;
}
if (itemActionViewLayout > 0) {
if (!actionViewSpecified) {
item.setActionView(itemActionViewLayout);
actionViewSpecified = true;
} else {
Log.w(LOG_TAG, "Ignoring attribute 'itemActionViewLayout'."
+ " Action view already specified.");
}
}
if (itemActionProvider != null) {
item.setActionProvider(itemActionProvider);
}
}
public void addItem() {
itemAdded = true;
setItem(menu.add(groupId, itemId, itemCategoryOrder, itemTitle));
}
public SubMenu addSubMenuItem() {
itemAdded = true;
SubMenu subMenu = menu.addSubMenu(groupId, itemId, itemCategoryOrder, itemTitle);
setItem(subMenu.getItem());
return subMenu;
}
public boolean hasAddedItem() {
return itemAdded;
}
@SuppressWarnings("unchecked")
private T newInstance(String className, Class[] constructorSignature,
Object[] arguments) {
try {
Class clazz = mContext.getClassLoader().loadClass(className);
Constructor constructor = clazz.getConstructor(constructorSignature);
return (T) constructor.newInstance(arguments);
} catch (Exception e) {
Log.w(LOG_TAG, "Cannot instantiate class: " + className, e);
}
return null;
}
}
}