10.24 笔记 android 图片验证码的生成

最新推荐文章于 2025-12-31 19:19:25 发布

转载最新推荐文章于 2025-12-31 19:19:25 发布 · 700 阅读

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#android #bitmap #验证码

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本文介绍了如何利用Java和Android开发一个自定义的验证码生成工具类，并讨论了将其作为库工程的应用注意事项。同时，展示了如何在Android布局中集成该工具类并实现刷新验证码的功能。最后，提供了将一个Android工程作为库工程时需遵循的几个关键点。

转载：

http://www.eoeandroid.com/thread-329148-1-1.html

package com.example.demo3;


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 =5;  
    private static final int DEFAULT_FONT_SIZE = 45;  
    private static final int DEFAULT_LINE_NUMBER = 1;  
    private static final int BASE_PADDING_LEFT = 25, 
    		RANGE_PADDING_LEFT =30, BASE_PADDING_TOP =30, 
    		RANGE_PADDING_TOP = 25;  
    private static final int DEFAULT_WIDTH = 300, DEFAULT_HEIGHT =80; 
    //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  
        paint.setFakeBoldText(true);
        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：

imageView.setImageBitmap(bpUtil.getInstance().createBitmap());
sss=bpUtil.getInstance().getCode();

刷新验证码：

imageView.setImageBitmap(bpUtil.getInstance().createBitmap());
sss=bpUtil.getInstance().getCode();

个人看法：

randomColor(int rate) {

}

rate可以直接去掉

可以考虑做成自定义view，代码是个工具类，宽高写死，没有适配的功能~

转载：

http://www.eoeandroid.com/thread-550328-1-1.html

将一个Android工程作为library工程需要注意的内容：
1.library工程不能引用其他的library工程
2.library工程中不能有switch，case，case的值是R.xx.xx,因为这是的R文件中的值已经不是final类型的了，需要改成if，else
3.library工程中不能有assert，raw,因为访问不到了，但是可以将这些下面发到主工程下，你会发现神奇的一幕产生，它可以访问了
4.library工程中不能有aidl文件
5.library工程不能和主程序有相同名称的Layout，string，id,drawable,等等R下有定义的，否则会被主程序覆盖掉
6.library工程的所有Activity、Service、receiver、provider，还要添加library工程的permission、uses-library等属性，注意引用的组件要使用完全的包名，否则将报对应的NotFoundException。
7.library的sdk版本不能高于主程序，否则编译不通过。

（本人编码不太想要library，容易报错）

Canvas绘制文本沿着path绘制（文本会弯）

@Override
protected void onDraw(Canvas canvas) {
Path path = new Path(); //定义一条路径
path.moveTo(10,10); //移动到坐标10,10
path.lineTo(50,60);
path.lineTo(200,80);
path.lineTo(10, 10);
canvas.drawPath(path, paint);
canvas.drawTextOnPath("Android777开发者博客",
path, 10, 10, paint);
}

画跳到的心性

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.Typeface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class Love extends SurfaceView implements SurfaceHolder.Callback,
                Runnable {
        boolean mbloop = false;
        SurfaceHolder mSurfaceHolder = null;
        private Canvas canvas;
        int miCount = 0;
        int y = 50;

        public Love(Context context) {
                super(context);
                mSurfaceHolder = this.getHolder();
                mSurfaceHolder.addCallback(this);
                this.setFocusable(true);
                this.setKeepScreenOn(true);
                mbloop = true;
        }

        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                        int height) {
                // TODO Auto-generated method stub
        }

        @Override
        public void surfaceCreated(SurfaceHolder holder) {
                // TODO Auto-generated method stub
                new Thread(this).start();
        }

        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {
                // TODO Auto-generated method stub
                mbloop = false;
        }

        @Override
        public void run() {
                // TODO Auto-generated method stub
                while (mbloop) {
                        try {
                                Thread.sleep(200);
                        } catch (Exception e) {
                                // TODO: handle exception
                        }
                        synchronized (mSurfaceHolder) {
                                Draw();
                        }
                }
        }

        private void Draw() {
                // TODO Auto-generated method stub
                canvas = mSurfaceHolder.lockCanvas();
                try {
                        if (mSurfaceHolder == null || canvas == null) {
                                return;
                        }
                        if (miCount < 100) {
                                miCount++;
                        } else {
                                miCount = 0;
                        }
                        Paint paint = new Paint();
                        paint.setAntiAlias(true);
                        paint.setColor(Color.BLACK);
                        canvas.drawRect(0, 0, 320, 480, paint);
                        switch (miCount % 6) {
                        case 0:
                                paint.setColor(Color.BLUE);
                                break;
                        case 1:
                                paint.setColor(Color.GREEN);
                                break;
                        case 2:
                                paint.setColor(Color.RED);
                                break;
                        case 3:
                                paint.setColor(Color.YELLOW);
                                break;
                        case 4:
                                paint.setColor(Color.argb(255, 255, 181, 216));
                                break;
                        case 5:
                                paint.setColor(Color.argb(255, 0, 255, 255));
                                break;
                        default:
                                paint.setColor(Color.WHITE);
                                break;
                        }
                        int i, j;
                        double x, y, r;

                        for (i = 0; i <= 90; i++) {
                                for (j = 0; j <= 90; j++) {
                                        r = Math.PI / 45 * i * (1 - Math.sin(Math.PI / 45 * j))
                                                        * 20;
                                        x = r * Math.cos(Math.PI / 45 * j)
                                                        * Math.sin(Math.PI / 45 * i) + 320 / 2;
                                        y = -r * Math.sin(Math.PI / 45 * j) + 400 / 4;
                                        canvas.drawPoint((float) x, (float) y, paint);
                                }
                        }

                        paint.setTextSize(32);
                        paint.setTypeface(Typeface.create(Typeface.SERIF, Typeface.ITALIC));

                        RectF rect = new RectF(60, 400, 260, 405);
                        canvas.drawRoundRect(rect, (float) 1.0, (float) 1.0, paint);
                        canvas.drawText("Loving You", 75, 400, paint);
                        mSurfaceHolder.unlockCanvasAndPost(canvas);
                } catch (Exception e) {
                }
        }
}[/mw_shl_code]



[mw_shl_code=java,true]package com.example.love;

import android.os.Bundle;
import android.app.Activity;

public class MainActivity extends Activity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                Love love = new Love(this);
                setContentView(love);
        }

}[/mw_shl_code]