android生成验证码bitmap

http://blog.csdn.net/whumr1/article/details/7092013
不多说了，直接上代码，项目中用到的，未做优化，还有很多参数未设置。

[java] view plaincopy
import java.util.Random; 
 
import android.graphics.Bitmap; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.graphics.Bitmap.Config; 
 
public class BPUtil { 
     
    private static final char[] CHARS = { 
        '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 
        'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',  
        'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',  
        'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' 
    }; 
     
    private static BPUtil bpUtil; 
     
    public static BPUtil getInstance() { 
        if(bpUtil == null) 
            bpUtil = new BPUtil(); 
        return bpUtil; 
    } 
     
//  width="60" height="30"  
//          base_padding_left="5" 
//          range_padding_left="10" 
//          base_padding_top="15" 
//          range_padding_top="10" 
//          codeLength="4" 
//          line_number="3" 
//          font_size="20" 
     
    //default settings 
    private static final int DEFAULT_CODE_LENGTH = 4; 
    private static final int DEFAULT_FONT_SIZE = 20; 
    private static final int DEFAULT_LINE_NUMBER = 3; 
    private static final int BASE_PADDING_LEFT = 5, RANGE_PADDING_LEFT = 10, BASE_PADDING_TOP = 15, RANGE_PADDING_TOP = 10; 
    private static final int DEFAULT_WIDTH = 60, DEFAULT_HEIGHT = 30; 
     
    //settings decided by the layout xml 
    //canvas width and height 
    private int width = DEFAULT_WIDTH, height = DEFAULT_HEIGHT;  
     
    //random word space and pading_top 
    private int base_padding_left = BASE_PADDING_LEFT, range_padding_left = RANGE_PADDING_LEFT,  
            base_padding_top = BASE_PADDING_TOP, range_padding_top = RANGE_PADDING_TOP; 
     
    //number of chars, lines; font size 
    private int codeLength = DEFAULT_CODE_LENGTH, line_number = DEFAULT_LINE_NUMBER, font_size = DEFAULT_FONT_SIZE; 
     
    //variables 
    private String code; 
    private int padding_left, padding_top; 
    private Random random = new Random(); 
     
    public Bitmap createBitmap() { 
        padding_left = 0; 
         
        Bitmap bp = Bitmap.createBitmap(width, height, Config.ARGB_8888);  
        Canvas c = new Canvas(bp); 
 
        code = createCode(); 
         
        c.drawColor(Color.WHITE); 
        Paint paint = new Paint(); 
        paint.setTextSize(font_size); 
         
        for (int i = 0; i < code.length(); i++) { 
            randomTextStyle(paint); 
            randomPadding(); 
            c.drawText(code.charAt(i) + "", padding_left, padding_top, paint); 
        } 
 
        for (int i = 0; i < line_number; i++) { 
            drawLine(c, paint); 
        } 
         
        c.save( Canvas.ALL_SAVE_FLAG );//保存   
        c.restore();// 
        return bp; 
    } 
     
    public String getCode() { 
        return code; 
    } 
     
    private String createCode() { 
        StringBuilder buffer = new StringBuilder(); 
        for (int i = 0; i < codeLength; i++) { 
            buffer.append(CHARS[random.nextInt(CHARS.length)]); 
        } 
        return buffer.toString(); 
    } 
     
    private void drawLine(Canvas canvas, Paint paint) { 
        int color = randomColor(); 
        int startX = random.nextInt(width); 
        int startY = random.nextInt(height); 
        int stopX = random.nextInt(width); 
        int stopY = random.nextInt(height); 
        paint.setStrokeWidth(1); 
        paint.setColor(color); 
        canvas.drawLine(startX, startY, stopX, stopY, paint); 
    } 
     
    private int randomColor() { 
        return randomColor(1); 
    } 
 
    private int randomColor(int rate) { 
        int red = random.nextInt(256) / rate; 
        int green = random.nextInt(256) / rate; 
        int blue = random.nextInt(256) / rate; 
        return Color.rgb(red, green, blue); 
    } 
     
    private void randomTextStyle(Paint paint) { 
        int color = randomColor(); 
        paint.setColor(color); 
        paint.setFakeBoldText(random.nextBoolean());  //true为粗体，false为非粗体 
        float skewX = random.nextInt(11) / 10; 
        skewX = random.nextBoolean() ? skewX : -skewX; 
        paint.setTextSkewX(skewX); //float类型参数，负数表示右斜，整数左斜 
//      paint.setUnderlineText(true); //true为下划线，false为非下划线 
//      paint.setStrikeThruText(true); //true为删除线，false为非删除线 
    } 
     
    private void randomPadding() { 
        padding_left += base_padding_left + random.nextInt(range_padding_left); 
        padding_top = base_padding_top + random.nextInt(range_padding_top); 
    } 
} 

使用方法

[java] view plaincopy
ImageView imageView = (ImageView)findViewById(R.id.imageView); 
imageView.setImageBitmap(BPUtil.getInstance().createBitmap());