1/* 2 * Copyright (C) 2010 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 17package com.android.internal.policy.impl; 18 19import android.content.Context; 20import android.graphics.Canvas; 21import android.graphics.Rect; 22import android.graphics.drawable.Drawable; 23import android.util.AttributeSet; 24import android.view.Gravity; 25import android.view.View; 26import android.widget.LinearLayout; 27 28/** 29 * A vertical linear layout. However, instead of drawing the background 30 * behnd the items, it draws the background outside the items based on the 31 * padding. If there isn't enough room to draw both, it clips the background 32 * instead of the contents. 33 */ 34public class RecentApplicationsBackground extends LinearLayout { 35 private static final String TAG = "RecentApplicationsBackground"; 36 37 private boolean mBackgroundSizeChanged; 38 private Drawable mBackground; 39 private Rect mTmp0 = new Rect(); 40 private Rect mTmp1 = new Rect(); 41 42 public RecentApplicationsBackground(Context context) { 43 this(context, null); 44 init(); 45 } 46 47 public RecentApplicationsBackground(Context context, AttributeSet attrs) { 48 super(context, attrs); 49 init(); 50 } 51 52 private void init() { 53 mBackground = getBackground(); 54 setBackgroundDrawable(null); 55 setPadding(0, 0, 0, 0); 56 setGravity(Gravity.CENTER); 57 } 58 59 @Override 60 protected boolean setFrame(int left, int top, int right, int bottom) { 61 setWillNotDraw(false); 62 if (mLeft != left || mRight != right || mTop != top || mBottom != bottom) { 63 mBackgroundSizeChanged = true; 64 } 65 return super.setFrame(left, top, right, bottom); 66 } 67 68 @Override 69 protected boolean verifyDrawable(Drawable who) { 70 return who == mBackground || super.verifyDrawable(who); 71 } 72 73 @Override 74 public void jumpDrawablesToCurrentState() { 75 super.jumpDrawablesToCurrentState(); 76 if (mBackground != null) mBackground.jumpToCurrentState(); 77 } 78 79 @Override 80 protected void drawableStateChanged() { 81 Drawable d = mBackground; 82 if (d != null && d.isStateful()) { 83 d.setState(getDrawableState()); 84 } 85 super.drawableStateChanged(); 86 } 87 88 @Override 89 public void draw(Canvas canvas) { 90 final Drawable background = mBackground; 91 if (background != null) { 92 if (mBackgroundSizeChanged) { 93 mBackgroundSizeChanged = false; 94 Rect chld = mTmp0; 95 Rect bkg = mTmp1; 96 mBackground.getPadding(bkg); 97 getChildBounds(chld); 98 // This doesn't clamp to this view's bounds, which is what we want, 99 // so that the drawing is clipped. 100 final int top = chld.top - bkg.top; 101 final int bottom = chld.bottom + bkg.bottom; 102 // The background here is a gradient that wants to 103 // extend the full width of the screen (whatever that 104 // may be). 105 int left, right; 106 if (false) { 107 // This limits the width of the drawable. 108 left = chld.left - bkg.left; 109 right = chld.right + bkg.right; 110 } else { 111 // This expands it to full width. 112 left = 0; 113 right = getRight(); 114 } 115 background.setBounds(left, top, right, bottom); 116 } 117 } 118 mBackground.draw(canvas); 119 120 if (false) { 121 android.graphics.Paint p = new android.graphics.Paint(); 122 p.setColor(0x88ffff00); 123 canvas.drawRect(background.getBounds(), p); 124 } 125 canvas.drawARGB((int)(0.75*0xff), 0, 0, 0); 126 127 super.draw(canvas); 128 } 129 130 @Override 131 protected void onAttachedToWindow() { 132 super.onAttachedToWindow(); 133 mBackground.setCallback(this); 134 setWillNotDraw(false); 135 } 136 137 @Override 138 protected void onDetachedFromWindow() { 139 super.onDetachedFromWindow(); 140 mBackground.setCallback(null); 141 } 142 143 private void getChildBounds(Rect r) { 144 r.left = r.top = Integer.MAX_VALUE; 145 r.bottom = r.right = Integer.MIN_VALUE; 146 final int N = getChildCount(); 147 for (int i=0; i<N; i++) { 148 View v = getChildAt(i); 149 if (v.getVisibility() == View.VISIBLE) { 150 r.left = Math.min(r.left, v.getLeft()); 151 r.top = Math.min(r.top, v.getTop()); 152 r.right = Math.max(r.right, v.getRight()); 153 r.bottom = Math.max(r.bottom, v.getBottom()); 154 } 155 } 156 } 157} 158