/** * Copyright (C) 2015 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 com.android.launcher3.util; import android.util.Log; import android.view.View; import android.view.View.OnAttachStateChangeListener; import android.view.ViewTreeObserver.OnDrawListener; import com.android.launcher3.DeferredHandler; import com.android.launcher3.Launcher; import java.util.ArrayList; import java.util.concurrent.Executor; /** * An executor which runs all the tasks after the first onDraw is called on the target view. */ public class ViewOnDrawExecutor implements Executor, OnDrawListener, Runnable, OnAttachStateChangeListener { private final ArrayList<Runnable> mTasks = new ArrayList<>(); private final DeferredHandler mHandler; private Launcher mLauncher; private View mAttachedView; private boolean mCompleted; private boolean mLoadAnimationCompleted; private boolean mFirstDrawCompleted; public ViewOnDrawExecutor(DeferredHandler handler) { mHandler = handler; } public void attachTo(Launcher launcher) { mLauncher = launcher; mAttachedView = launcher.getWorkspace(); mAttachedView.addOnAttachStateChangeListener(this); attachObserver(); } private void attachObserver() { if (!mCompleted) { mAttachedView.getViewTreeObserver().addOnDrawListener(this); } } @Override public void execute(Runnable command) { mTasks.add(command); } @Override public void onViewAttachedToWindow(View v) { attachObserver(); } @Override public void onViewDetachedFromWindow(View v) { } @Override public void onDraw() { mFirstDrawCompleted = true; mAttachedView.post(this); } public void onLoadAnimationCompleted() { mLoadAnimationCompleted = true; if (mAttachedView != null) { mAttachedView.post(this); } } @Override public void run() { // Post the pending tasks after both onDraw and onLoadAnimationCompleted have been called. if (mLoadAnimationCompleted && mFirstDrawCompleted && !mCompleted) { for (final Runnable r : mTasks) { mHandler.post(r); } markCompleted(); } } public void markCompleted() { mTasks.clear(); mCompleted = true; if (mAttachedView != null) { mAttachedView.getViewTreeObserver().removeOnDrawListener(this); mAttachedView.removeOnAttachStateChangeListener(this); } if (mLauncher != null) { mLauncher.clearPendingExecutor(this); } } }