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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2007 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 android.widget;
import android.annotation.IntDef;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.StringRes;
import android.app.INotificationManager;
import android.app.ITransientNotification;
import android.content.Context;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.graphics.PixelFormat;
import android.os.Handler;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.os.RemoteException;
import android.os.ServiceManager;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.WindowManager;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityManager;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
/**
* A toast is a view containing a quick little message for the user. The toast class
* helps you create and show those.
* {@more}
*
*
* When the view is shown to the user, appears as a floating view over the
* application. It will never receive focus. The user will probably be in the
* middle of typing something else. The idea is to be as unobtrusive as
* possible, while still showing the user the information you want them to see.
* Two examples are the volume control, and the brief message saying that your
* settings have been saved.
*
* The easiest way to use this class is to call one of the static methods that constructs
* everything you need and returns a new Toast object.
*
*
* Developer Guides
* For information about creating Toast notifications, read the
* Toast Notifications developer
* guide.
*
*/
public class Toast {
static final String TAG = "Toast";
static final boolean localLOGV = false;
/** @hide */
@IntDef(prefix = { "LENGTH_" }, value = {
LENGTH_SHORT,
LENGTH_LONG
})
@Retention(RetentionPolicy.SOURCE)
public @interface Duration {}
/**
* Show the view or text notification for a short period of time. This time
* could be user-definable. This is the default.
* @see #setDuration
*/
public static final int LENGTH_SHORT = 0;
/**
* Show the view or text notification for a long period of time. This time
* could be user-definable.
* @see #setDuration
*/
public static final int LENGTH_LONG = 1;
final Context mContext;
final TN mTN;
int mDuration;
View mNextView;
/**
* Construct an empty Toast object. You must call {@link #setView} before you
* can call {@link #show}.
*
* @param context The context to use. Usually your {@link android.app.Application}
* or {@link android.app.Activity} object.
*/
public Toast(Context context) {
this(context, null);
}
/**
* Constructs an empty Toast object. If looper is null, Looper.myLooper() is used.
* @hide
*/
public Toast(@NonNull Context context, @Nullable Looper looper) {
mContext = context;
mTN = new TN(context.getPackageName(), looper);
mTN.mY = context.getResources().getDimensionPixelSize(
com.android.internal.R.dimen.toast_y_offset);
mTN.mGravity = context.getResources().getInteger(
com.android.internal.R.integer.config_toastDefaultGravity);
}
/**
* Show the view for the specified duration.
*/
public void show() {
if (mNextView == null) {
throw new RuntimeException("setView must have been called");
}
INotificationManager service = getService();
String pkg = mContext.getOpPackageName();
TN tn = mTN;
tn.mNextView = mNextView;
try {
service.enqueueToast(pkg, tn, mDuration);
} catch (RemoteException e) {
// Empty
}
}
/**
* Close the view if it's showing, or don't show it if it isn't showing yet.
* You do not normally have to call this. Normally view will disappear on its own
* after the appropriate duration.
*/
public void cancel() {
mTN.cancel();
}
/**
* Set the view to show.
* @see #getView
*/
public void setView(View view) {
mNextView = view;
}
/**
* Return the view.
* @see #setView
*/
public View getView() {
return mNextView;
}
/**
* Set how long to show the view for.
* @see #LENGTH_SHORT
* @see #LENGTH_LONG
*/
public void setDuration(@Duration int duration) {
mDuration = duration;
mTN.mDuration = duration;
}
/**
* Return the duration.
* @see #setDuration
*/
@Duration
public int getDuration() {
return mDuration;
}
/**
* Set the margins of the view.
*
* @param horizontalMargin The horizontal margin, in percentage of the
* container width, between the container's edges and the
* notification
* @param verticalMargin The vertical margin, in percentage of the
* container height, between the container's edges and the
* notification
*/
public void setMargin(float horizontalMargin, float verticalMargin) {
mTN.mHorizontalMargin = horizontalMargin;
mTN.mVerticalMargin = verticalMargin;
}
/**
* Return the horizontal margin.
*/
public float getHorizontalMargin() {
return mTN.mHorizontalMargin;
}
/**
* Return the vertical margin.
*/
public float getVerticalMargin() {
return mTN.mVerticalMargin;
}
/**
* Set the location at which the notification should appear on the screen.
* @see android.view.Gravity
* @see #getGravity
*/
public void setGravity(int gravity, int xOffset, int yOffset) {
mTN.mGravity = gravity;
mTN.mX = xOffset;
mTN.mY = yOffset;
}
/**
* Get the location at which the notification should appear on the screen.
* @see android.view.Gravity
* @see #getGravity
*/
public int getGravity() {
return mTN.mGravity;
}
/**
* Return the X offset in pixels to apply to the gravity's location.
*/
public int getXOffset() {
return mTN.mX;
}
/**
* Return the Y offset in pixels to apply to the gravity's location.
*/
public int getYOffset() {
return mTN.mY;
}
/**
* Gets the LayoutParams for the Toast window.
* @hide
*/
public WindowManager.LayoutParams getWindowParams() {
return mTN.mParams;
}
/**
* Make a standard toast that just contains a text view.
*
* @param context The context to use. Usually your {@link android.app.Application}
* or {@link android.app.Activity} object.
* @param text The text to show. Can be formatted text.
* @param duration How long to display the message. Either {@link #LENGTH_SHORT} or
* {@link #LENGTH_LONG}
*
*/
public static Toast makeText(Context context, CharSequence text, @Duration int duration) {
return makeText(context, null, text, duration);
}
/**
* Make a standard toast to display using the specified looper.
* If looper is null, Looper.myLooper() is used.
* @hide
*/
public static Toast makeText(@NonNull Context context, @Nullable Looper looper,
@NonNull CharSequence text, @Duration int duration) {
Toast result = new Toast(context, looper);
LayoutInflater inflate = (LayoutInflater)
context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflate.inflate(com.android.internal.R.layout.transient_notification, null);
TextView tv = (TextView)v.findViewById(com.android.internal.R.id.message);
tv.setText(text);
result.mNextView = v;
result.mDuration = duration;
return result;
}
/**
* Make a standard toast that just contains a text view with the text from a resource.
*
* @param context The context to use. Usually your {@link android.app.Application}
* or {@link android.app.Activity} object.
* @param resId The resource id of the string resource to use. Can be formatted text.
* @param duration How long to display the message. Either {@link #LENGTH_SHORT} or
* {@link #LENGTH_LONG}
*
* @throws Resources.NotFoundException if the resource can't be found.
*/
public static Toast makeText(Context context, @StringRes int resId, @Duration int duration)
throws Resources.NotFoundException {
return makeText(context, context.getResources().getText(resId), duration);
}
/**
* Update the text in a Toast that was previously created using one of the makeText() methods.
* @param resId The new text for the Toast.
*/
public void setText(@StringRes int resId) {
setText(mContext.getText(resId));
}
/**
* Update the text in a Toast that was previously created using one of the makeText() methods.
* @param s The new text for the Toast.
*/
public void setText(CharSequence s) {
if (mNextView == null) {
throw new RuntimeException("This Toast was not created with Toast.makeText()");
}
TextView tv = mNextView.findViewById(com.android.internal.R.id.message);
if (tv == null) {
throw new RuntimeException("This Toast was not created with Toast.makeText()");
}
tv.setText(s);
}
// =======================================================================================
// All the gunk below is the interaction with the Notification Service, which handles
// the proper ordering of these system-wide.
// =======================================================================================
private static INotificationManager sService;
static private INotificationManager getService() {
if (sService != null) {
return sService;
}
sService = INotificationManager.Stub.asInterface(ServiceManager.getService("notification"));
return sService;
}
private static class TN extends ITransientNotification.Stub {
private final WindowManager.LayoutParams mParams = new WindowManager.LayoutParams();
private static final int SHOW = 0;
private static final int HIDE = 1;
private static final int CANCEL = 2;
final Handler mHandler;
int mGravity;
int mX, mY;
float mHorizontalMargin;
float mVerticalMargin;
View mView;
View mNextView;
int mDuration;
WindowManager mWM;
String mPackageName;
static final long SHORT_DURATION_TIMEOUT = 4000;
static final long LONG_DURATION_TIMEOUT = 7000;
TN(String packageName, @Nullable Looper looper) {
// XXX This should be changed to use a Dialog, with a Theme.Toast
// defined that sets up the layout params appropriately.
final WindowManager.LayoutParams params = mParams;
params.height = WindowManager.LayoutParams.WRAP_CONTENT;
params.width = WindowManager.LayoutParams.WRAP_CONTENT;
params.format = PixelFormat.TRANSLUCENT;
params.windowAnimations = com.android.internal.R.style.Animation_Toast;
params.type = WindowManager.LayoutParams.TYPE_TOAST;
params.setTitle("Toast");
params.flags = WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
| WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
| WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;
mPackageName = packageName;
if (looper == null) {
// Use Looper.myLooper() if looper is not specified.
looper = Looper.myLooper();
if (looper == null) {
throw new RuntimeException(
"Can't toast on a thread that has not called Looper.prepare()");
}
}
mHandler = new Handler(looper, null) {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case SHOW: {
IBinder token = (IBinder) msg.obj;
handleShow(token);
break;
}
case HIDE: {
handleHide();
// Don't do this in handleHide() because it is also invoked by
// handleShow()
mNextView = null;
break;
}
case CANCEL: {
handleHide();
// Don't do this in handleHide() because it is also invoked by
// handleShow()
mNextView = null;
try {
getService().cancelToast(mPackageName, TN.this);
} catch (RemoteException e) {
}
break;
}
}
}
};
}
/**
* schedule handleShow into the right thread
*/
@Override
public void show(IBinder windowToken) {
if (localLOGV) Log.v(TAG, "SHOW: " + this);
mHandler.obtainMessage(SHOW, windowToken).sendToTarget();
}
/**
* schedule handleHide into the right thread
*/
@Override
public void hide() {
if (localLOGV) Log.v(TAG, "HIDE: " + this);
mHandler.obtainMessage(HIDE).sendToTarget();
}
public void cancel() {
if (localLOGV) Log.v(TAG, "CANCEL: " + this);
mHandler.obtainMessage(CANCEL).sendToTarget();
}
public void handleShow(IBinder windowToken) {
if (localLOGV) Log.v(TAG, "HANDLE SHOW: " + this + " mView=" + mView
+ " mNextView=" + mNextView);
// If a cancel/hide is pending - no need to show - at this point
// the window token is already invalid and no need to do any work.
if (mHandler.hasMessages(CANCEL) || mHandler.hasMessages(HIDE)) {
return;
}
if (mView != mNextView) {
// remove the old view if necessary
handleHide();
mView = mNextView;
Context context = mView.getContext().getApplicationContext();
String packageName = mView.getContext().getOpPackageName();
if (context == null) {
context = mView.getContext();
}
mWM = (WindowManager)context.getSystemService(Context.WINDOW_SERVICE);
// We can resolve the Gravity here by using the Locale for getting
// the layout direction
final Configuration config = mView.getContext().getResources().getConfiguration();
final int gravity = Gravity.getAbsoluteGravity(mGravity, config.getLayoutDirection());
mParams.gravity = gravity;
if ((gravity & Gravity.HORIZONTAL_GRAVITY_MASK) == Gravity.FILL_HORIZONTAL) {
mParams.horizontalWeight = 1.0f;
}
if ((gravity & Gravity.VERTICAL_GRAVITY_MASK) == Gravity.FILL_VERTICAL) {
mParams.verticalWeight = 1.0f;
}
mParams.x = mX;
mParams.y = mY;
mParams.verticalMargin = mVerticalMargin;
mParams.horizontalMargin = mHorizontalMargin;
mParams.packageName = packageName;
mParams.hideTimeoutMilliseconds = mDuration ==
Toast.LENGTH_LONG ? LONG_DURATION_TIMEOUT : SHORT_DURATION_TIMEOUT;
mParams.token = windowToken;
if (mView.getParent() != null) {
if (localLOGV) Log.v(TAG, "REMOVE! " + mView + " in " + this);
mWM.removeView(mView);
}
if (localLOGV) Log.v(TAG, "ADD! " + mView + " in " + this);
// Since the notification manager service cancels the token right
// after it notifies us to cancel the toast there is an inherent
// race and we may attempt to add a window after the token has been
// invalidated. Let us hedge against that.
try {
mWM.addView(mView, mParams);
trySendAccessibilityEvent();
} catch (WindowManager.BadTokenException e) {
/* ignore */
}
}
}
private void trySendAccessibilityEvent() {
AccessibilityManager accessibilityManager =
AccessibilityManager.getInstance(mView.getContext());
if (!accessibilityManager.isEnabled()) {
return;
}
// treat toasts as notifications since they are used to
// announce a transient piece of information to the user
AccessibilityEvent event = AccessibilityEvent.obtain(
AccessibilityEvent.TYPE_NOTIFICATION_STATE_CHANGED);
event.setClassName(getClass().getName());
event.setPackageName(mView.getContext().getPackageName());
mView.dispatchPopulateAccessibilityEvent(event);
accessibilityManager.sendAccessibilityEvent(event);
}
public void handleHide() {
if (localLOGV) Log.v(TAG, "HANDLE HIDE: " + this + " mView=" + mView);
if (mView != null) {
// note: checking parent() just to make sure the view has
// been added... i have seen cases where we get here when
// the view isn't yet added, so let's try not to crash.
if (mView.getParent() != null) {
if (localLOGV) Log.v(TAG, "REMOVE! " + mView + " in " + this);
mWM.removeViewImmediate(mView);
}
// Now that we've removed the view it's safe for the server to release
// the resources.
try {
getService().finishToken(mPackageName, this);
} catch (RemoteException e) {
}
mView = null;
}
}
}
}