1 /*
2  * Copyright (C) 2008 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.example.android.apis.graphics;
18 
19 import android.content.Context;
20 import android.graphics.*;
21 import android.os.Bundle;
22 import android.view.*;
23 
24 public class Layers extends GraphicsActivity {
25 
26     @Override
onCreate(Bundle savedInstanceState)27     protected void onCreate(Bundle savedInstanceState) {
28         super.onCreate(savedInstanceState);
29         setContentView(new SampleView(this));
30     }
31 
32     private static class SampleView extends View {
33         private Paint mPaint;
34 
SampleView(Context context)35         public SampleView(Context context) {
36             super(context);
37             setFocusable(true);
38 
39             mPaint = new Paint();
40             mPaint.setAntiAlias(true);
41         }
42 
onDraw(Canvas canvas)43         @Override protected void onDraw(Canvas canvas) {
44             canvas.drawColor(Color.WHITE);
45 
46             canvas.translate(10, 10);
47 
48             canvas.saveLayerAlpha(0, 0, 200, 200, 0x88);
49 
50             mPaint.setColor(Color.RED);
51             canvas.drawCircle(75, 75, 75, mPaint);
52             mPaint.setColor(Color.BLUE);
53             canvas.drawCircle(125, 125, 75, mPaint);
54 
55             canvas.restore();
56         }
57     }
58 }
59 
60