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 com.example.android.apis.R; 20 21 import android.app.Activity; 22 import android.content.Context; 23 import android.graphics.*; 24 import android.os.Bundle; 25 import android.view.KeyEvent; 26 import android.view.*; 27 28 public class TextAlign extends GraphicsActivity { 29 30 @Override 31 protected void onCreate(Bundle savedInstanceState) { 32 super.onCreate(savedInstanceState); 33 setContentView(new SampleView(this)); 34 } 35 36 private static class SampleView extends View { 37 private Paint mPaint; 38 private float mX; 39 private float[] mPos; 40 41 private Path mPath; 42 private Paint mPathPaint; 43 44 private static final int DY = 30; 45 private static final String TEXT_L = "Left"; 46 private static final String TEXT_C = "Center"; 47 private static final String TEXT_R = "Right"; 48 private static final String POSTEXT = "Positioned"; 49 private static final String TEXTONPATH = "Along a path"; 50 51 private static void makePath(Path p) { 52 p.moveTo(10, 0); 53 p.cubicTo(100, -50, 200, 50, 300, 0); 54 } 55 56 private float[] buildTextPositions(String text, float y, Paint paint) { 57 float[] widths = new float[text.length()]; 58 // initially get the widths for each char 59 int n = paint.getTextWidths(text, widths); 60 // now popuplate the array, interleaving spaces for the Y values 61 float[] pos = new float[n * 2]; 62 float accumulatedX = 0; 63 for (int i = 0; i < n; i++) { 64 pos[i*2 + 0] = accumulatedX; 65 pos[i*2 + 1] = y; 66 accumulatedX += widths[i]; 67 } 68 return pos; 69 } 70 71 public SampleView(Context context) { 72 super(context); 73 setFocusable(true); 74 75 mPaint = new Paint(); 76 mPaint.setAntiAlias(true); 77 mPaint.setTextSize(30); 78 mPaint.setTypeface(Typeface.SERIF); 79 80 mPos = buildTextPositions(POSTEXT, 0, mPaint); 81 82 mPath = new Path(); 83 makePath(mPath); 84 85 mPathPaint = new Paint(); 86 mPathPaint.setAntiAlias(true); 87 mPathPaint.setColor(0x800000FF); 88 mPathPaint.setStyle(Paint.Style.STROKE); 89 } 90 91 @Override protected void onDraw(Canvas canvas) { 92 canvas.drawColor(Color.WHITE); 93 94 Paint p = mPaint; 95 float x = mX; 96 float y = 0; 97 float[] pos = mPos; 98 99 // draw the normal strings 100 101 p.setColor(0x80FF0000); 102 canvas.drawLine(x, y, x, y+DY*3, p); 103 p.setColor(Color.BLACK); 104 105 canvas.translate(0, DY); 106 p.setTextAlign(Paint.Align.LEFT); 107 canvas.drawText(TEXT_L, x, y, p); 108 109 canvas.translate(0, DY); 110 p.setTextAlign(Paint.Align.CENTER); 111 canvas.drawText(TEXT_C, x, y, p); 112 113 canvas.translate(0, DY); 114 p.setTextAlign(Paint.Align.RIGHT); 115 canvas.drawText(TEXT_R, x, y, p); 116 117 canvas.translate(100, DY*2); 118 119 // now draw the positioned strings 120 121 p.setColor(0xBB00FF00); 122 for (int i = 0; i < pos.length/2; i++) { 123 canvas.drawLine(pos[i*2+0], pos[i*2+1]-DY, 124 pos[i*2+0], pos[i*2+1]+DY*2, p); 125 } 126 p.setColor(Color.BLACK); 127 128 p.setTextAlign(Paint.Align.LEFT); 129 canvas.drawPosText(POSTEXT, pos, p); 130 131 canvas.translate(0, DY); 132 p.setTextAlign(Paint.Align.CENTER); 133 canvas.drawPosText(POSTEXT, pos, p); 134 135 canvas.translate(0, DY); 136 p.setTextAlign(Paint.Align.RIGHT); 137 canvas.drawPosText(POSTEXT, pos, p); 138 139 // now draw the text on path 140 141 canvas.translate(-100, DY*2); 142 143 canvas.drawPath(mPath, mPathPaint); 144 p.setTextAlign(Paint.Align.LEFT); 145 canvas.drawTextOnPath(TEXTONPATH, mPath, 0, 0, p); 146 147 canvas.translate(0, DY*1.5f); 148 canvas.drawPath(mPath, mPathPaint); 149 p.setTextAlign(Paint.Align.CENTER); 150 canvas.drawTextOnPath(TEXTONPATH, mPath, 0, 0, p); 151 152 canvas.translate(0, DY*1.5f); 153 canvas.drawPath(mPath, mPathPaint); 154 p.setTextAlign(Paint.Align.RIGHT); 155 canvas.drawTextOnPath(TEXTONPATH, mPath, 0, 0, p); 156 } 157 158 @Override 159 protected void onSizeChanged(int w, int h, int ow, int oh) { 160 super.onSizeChanged(w, h, ow, oh); 161 mX = w * 0.5f; // remember the center of the screen 162 } 163 } 164 } 165 166
