1 /*
2  * Copyright (C) 2007 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.KeyEvent;
23 import android.view.View;
24 
25 public class PathEffects extends GraphicsActivity {
26 
27     @Override
onCreate(Bundle savedInstanceState)28     protected void onCreate(Bundle savedInstanceState) {
29         super.onCreate(savedInstanceState);
30         setContentView(new SampleView(this));
31     }
32 
33     private static class SampleView extends View {
34         private Paint mPaint;
35         private Path mPath;
36         private PathEffect[] mEffects;
37         private int[] mColors;
38         private float mPhase;
39 
makeDash(float phase)40         private static PathEffect makeDash(float phase) {
41             return new DashPathEffect(new float[] { 15, 5, 8, 5 }, phase);
42         }
43 
makeEffects(PathEffect[] e, float phase)44         private static void makeEffects(PathEffect[] e, float phase) {
45             e[0] = null;     // no effect
46             e[1] = new CornerPathEffect(10);
47             e[2] = new DashPathEffect(new float[] {10, 5, 5, 5}, phase);
48             e[3] = new PathDashPathEffect(makePathDash(), 12, phase,
49                                           PathDashPathEffect.Style.ROTATE);
50             e[4] = new ComposePathEffect(e[2], e[1]);
51             e[5] = new ComposePathEffect(e[3], e[1]);
52         }
53 
SampleView(Context context)54         public SampleView(Context context) {
55             super(context);
56             setFocusable(true);
57             setFocusableInTouchMode(true);
58 
59             mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
60             mPaint.setStyle(Paint.Style.STROKE);
61             mPaint.setStrokeWidth(6);
62 
63             mPath = makeFollowPath();
64 
65             mEffects = new PathEffect[6];
66 
67             mColors = new int[] { Color.BLACK, Color.RED, Color.BLUE,
68                                   Color.GREEN, Color.MAGENTA, Color.BLACK
69                                 };
70         }
71 
onDraw(Canvas canvas)72         @Override protected void onDraw(Canvas canvas) {
73             canvas.drawColor(Color.WHITE);
74 
75             RectF bounds = new RectF();
76             mPath.computeBounds(bounds, false);
77             canvas.translate(10 - bounds.left, 10 - bounds.top);
78 
79             makeEffects(mEffects, mPhase);
80             mPhase += 1;
81             invalidate();
82 
83             for (int i = 0; i < mEffects.length; i++) {
84                 mPaint.setPathEffect(mEffects[i]);
85                 mPaint.setColor(mColors[i]);
86                 canvas.drawPath(mPath, mPaint);
87                 canvas.translate(0, 28);
88             }
89         }
90 
onKeyDown(int keyCode, KeyEvent event)91         @Override public boolean onKeyDown(int keyCode, KeyEvent event) {
92             switch (keyCode) {
93                 case KeyEvent.KEYCODE_DPAD_CENTER:
94                     mPath = makeFollowPath();
95                     return true;
96             }
97             return super.onKeyDown(keyCode, event);
98         }
99 
makeFollowPath()100         private static Path makeFollowPath() {
101             Path p = new Path();
102             p.moveTo(0, 0);
103             for (int i = 1; i <= 15; i++) {
104                 p.lineTo(i*20, (float)Math.random() * 35);
105             }
106             return p;
107         }
108 
makePathDash()109         private static Path makePathDash() {
110             Path p = new Path();
111             p.moveTo(4, 0);
112             p.lineTo(0, -4);
113             p.lineTo(8, -4);
114             p.lineTo(12, 0);
115             p.lineTo(8, 4);
116             p.lineTo(0, 4);
117             return p;
118         }
119     }
120 }
121 
122