Android Clipping

Android Clipping

1. public class Clipping extends Activity {  
2.     protected void onCreate(Bundle savedInstanceState) {  
3.         super.onCreate(savedInstanceState);  
4.         setContentView(new SampleView(this));  
5.     }  
6.       
7.     private static class SampleView extends View {  
8.         private Paint mPaint;  
9.         private Path mPath;  
10.         public SampleView(Context context) {  
11.             super(context);  
12.             setFocusable(true);  
13.               
14.             mPaint = new Paint();  
15.             mPaint.setAntiAlias(true);  
16.             mPaint.setStrokeWidth(6);  
17.             mPaint.setTextSize(16);  
18.             mPaint.setTextAlign(Paint.Align.RIGHT);  
19.               
20.             mPath = new Path();  
21.         }  
22.           
23.         private void drawScene(Canvas canvas) {  
24.             canvas.clipRect(0, 0, 100, 100);  
25.               
26.             canvas.drawColor(Color.WHITE);  
27.               
28.             mPaint.setColor(Color.RED);  
29.             canvas.drawLine(0, 0, 100, 100, mPaint);  
30.               
31.             mPaint.setColor(Color.GREEN);  
32.             canvas.drawCircle(30, 70, 30, mPaint);  
33.               
34.             mPaint.setColor(Color.BLUE);  
35.             canvas.drawText("Clipping", 100, 30, mPaint);  
36.         }  
37.           
38.         @Override protected void onDraw(Canvas canvas) {  
39.             canvas.drawColor(Color.GRAY);              
40.             canvas.save();  
41.             canvas.translate(10, 10);  
42.             drawScene(canvas);  
43.             canvas.restore();  
44.               
45.             canvas.save();  
46.             canvas.translate(160, 10);  
47.             canvas.clipRect(10, 10, 90, 90);  
48.             canvas.clipRect(30, 30, 70, 70, Region.Op.DIFFERENCE);  
49.             drawScene(canvas);  
50.             canvas.restore();  
51.               
52.             canvas.save();  
53.             canvas.translate(10, 160);  
54.             mPath.reset();  
55.             canvas.clipPath(mPath); // makes the clip empty   
56.             mPath.addCircle(50, 50, 50, Path.Direction.CCW);  
57.             canvas.clipPath(mPath, Region.Op.REPLACE);  
58.             drawScene(canvas);  
59.             canvas.restore();  
60.               
61.             canvas.save();  
62.             canvas.translate(160, 160);  
63.             canvas.clipRect(0, 0, 60, 60);  
64.             canvas.clipRect(40, 40, 100, 100, Region.Op.UNION);  
65.             drawScene(canvas);  
66.             canvas.restore();  
67.               
68.             canvas.save();  
69.             canvas.translate(10, 310);  
70.             canvas.clipRect(0, 0, 60, 60);  
71.             canvas.clipRect(40, 40, 100, 100, Region.Op.XOR);  
72.             drawScene(canvas);  
73.             canvas.restore();  
74.               
75.             canvas.save();  
76.             canvas.translate(160, 310);  
77.             canvas.clipRect(0, 0, 60, 60);  
78.             canvas.clipRect(40, 40, 100, 100, Region.Op.REVERSE_DIFFERENCE);  
79.             drawScene(canvas);  
80.             canvas.restore();  
81.         }  
82.     }  
83. }