1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.contacts.util; 18 19 import android.view.View; 20 import android.view.ViewTreeObserver.OnGlobalLayoutListener; 21 import android.view.ViewTreeObserver.OnPreDrawListener; 22 23 /** Static methods that are useful for scheduling actions to occur at a later time. */ 24 public class SchedulingUtils { 25 26 27 /** Runs a piece of code after the next layout run */ doAfterLayout(final View view, final Runnable runnable)28 public static void doAfterLayout(final View view, final Runnable runnable) { 29 final OnGlobalLayoutListener listener = new OnGlobalLayoutListener() { 30 @Override 31 public void onGlobalLayout() { 32 // Layout pass done, unregister for further events 33 view.getViewTreeObserver().removeOnGlobalLayoutListener(this); 34 runnable.run(); 35 } 36 }; 37 view.getViewTreeObserver().addOnGlobalLayoutListener(listener); 38 } 39 40 /** Runs a piece of code just before the next draw, after layout and measurement */ doOnPreDraw(final View view, final boolean drawNextFrame, final Runnable runnable)41 public static void doOnPreDraw(final View view, final boolean drawNextFrame, 42 final Runnable runnable) { 43 final OnPreDrawListener listener = new OnPreDrawListener() { 44 @Override 45 public boolean onPreDraw() { 46 view.getViewTreeObserver().removeOnPreDrawListener(this); 47 runnable.run(); 48 return drawNextFrame; 49 } 50 }; 51 view.getViewTreeObserver().addOnPreDrawListener(listener); 52 } 53 } 54