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.*;
23 
24 public class MeasureText 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 final int WIDTH = 50;
33     private static final int HEIGHT = 50;
34     private static final int STRIDE = 64;   // must be >= WIDTH
35 
createColors()36     private static int[] createColors() {
37         int[] colors = new int[STRIDE * HEIGHT];
38         for (int y = 0; y < HEIGHT; y++) {
39             for (int x = 0; x < WIDTH; x++) {
40                 int r = x * 255 / (WIDTH - 1);
41                 int g = y * 255 / (HEIGHT - 1);
42                 int b = 255 - Math.min(r, g);
43                 int a = Math.max(r, g);
44                 colors[y * STRIDE + x] = (a << 24) | (r << 16) | (g << 8) | b;
45             }
46         }
47         return colors;
48     }
49 
50     private static class SampleView extends View {
51         private Paint   mPaint;
52         private float   mOriginX = 10;
53         private float   mOriginY = 80;
54 
SampleView(Context context)55         public SampleView(Context context) {
56             super(context);
57             setFocusable(true);
58 
59             mPaint = new Paint();
60             mPaint.setAntiAlias(true);
61             mPaint.setStrokeWidth(5);
62             mPaint.setStrokeCap(Paint.Cap.ROUND);
63             mPaint.setTextSize(64);
64             mPaint.setTypeface(Typeface.create(Typeface.SERIF,
65                                                Typeface.ITALIC));
66         }
67 
showText(Canvas canvas, String text, Paint.Align align)68         private void showText(Canvas canvas, String text, Paint.Align align) {
69          //   mPaint.setTextAlign(align);
70 
71             Rect    bounds = new Rect();
72             float[] widths = new float[text.length()];
73 
74             int count = mPaint.getTextWidths(text, 0, text.length(), widths);
75             float w = mPaint.measureText(text, 0, text.length());
76             mPaint.getTextBounds(text, 0, text.length(), bounds);
77 
78             mPaint.setColor(0xFF88FF88);
79             canvas.drawRect(bounds, mPaint);
80             mPaint.setColor(Color.BLACK);
81             canvas.drawText(text, 0, 0, mPaint);
82 
83             float[] pts = new float[2 + count*2];
84             float x = 0;
85             float y = 0;
86             pts[0] = x;
87             pts[1] = y;
88             for (int i = 0; i < count; i++) {
89                 x += widths[i];
90                 pts[2 + i*2] = x;
91                 pts[2 + i*2 + 1] = y;
92             }
93             mPaint.setColor(Color.RED);
94             mPaint.setStrokeWidth(0);
95             canvas.drawLine(0, 0, w, 0, mPaint);
96             mPaint.setStrokeWidth(5);
97             canvas.drawPoints(pts, 0, (count + 1) << 1, mPaint);
98         }
99 
onDraw(Canvas canvas)100         @Override protected void onDraw(Canvas canvas) {
101             canvas.drawColor(Color.WHITE);
102 
103             canvas.translate(mOriginX, mOriginY);
104 
105             showText(canvas, "Measure", Paint.Align.LEFT);
106             canvas.translate(0, 80);
107             showText(canvas, "wiggy!", Paint.Align.CENTER);
108             canvas.translate(0, 80);
109             showText(canvas, "Text", Paint.Align.RIGHT);
110         }
111     }
112 }
113