图片验证码

主要代码
我的Gitbub地址：https://github.com/shenglintang/LinCode

package com.example.pic_checkdemo;

import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.util.Log;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;

import java.util.Random;

/**
* Created by Jackie on 2015/12/1. 用于图片验证码的工具类
*/
public class CodeUtils {
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 CodeUtils mCodeUtils;
private int mPaddingLeft, mPaddingTop;
private StringBuilder mBuilder = new StringBuilder();
private Random mRandom = new Random();
private String code;
// Default Settings
private static final int DEFAULT_CODE_LENGTH = 4;// 验证码的长度 这里是4位
private static final int DEFAULT_FONT_SIZE = 60;// 字体大小
private static final int DEFAULT_LINE_NUMBER = 3;// 多少条干扰线
private static final int BASE_PADDING_LEFT = 20; // 左边距
private static final int RANGE_PADDING_LEFT = 35;// 左边距范围值
private static final int BASE_PADDING_TOP = 42;// 上边距
private static final int RANGE_PADDING_TOP = 15;// 上边距范围值
private static final int DEFAULT_WIDTH = 200;// 默认宽度.图片的总宽
private static final int DEFAULT_HEIGHT = 100;// 默认高度.图片的总高
private static final int DEFAULT_COLOR = 0xDF;// 默认背景颜色值

public static CodeUtils getInstance() {
    if (mCodeUtils == null) {
        mCodeUtils = new CodeUtils();
    }
    return mCodeUtils;
}

// 生成验证码图片
public Bitmap createBitmap() {
    mPaddingLeft = 0; // 每次生成验证码图片时初始化
    mPaddingTop = 0;

    Bitmap bitmap = Bitmap.createBitmap(DEFAULT_WIDTH, DEFAULT_HEIGHT, Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);

    // 生成的验证码
    String code = createCode();

    canvas.drawColor(Color.rgb(DEFAULT_COLOR, DEFAULT_COLOR, DEFAULT_COLOR));
    Paint paint = new Paint();
    paint.setTextSize(DEFAULT_FONT_SIZE);
    Log.e("111111111", code);
    for (int i = 0; i < code.length(); i++) {
        randomTextStyle(paint);
        randomPadding();
        canvas.drawText(code.charAt(i) + "", mPaddingLeft, mPaddingTop, paint);
    }

    // 干扰线
    for (int i = 0; i < DEFAULT_LINE_NUMBER; i++) {
        drawLine(canvas, paint);
    }

    canvas.save(Canvas.ALL_SAVE_FLAG);// 保存
    canvas.restore();
    return bitmap;
}

// 生成验证码
public String createCode() {
    mBuilder.delete(0, mBuilder.length()); // 使用之前首先清空内容

    for (int i = 0; i < DEFAULT_CODE_LENGTH; i++) {
        mBuilder.append(CHARS[mRandom.nextInt(CHARS.length)]);
    }
    code = mBuilder.toString();
    return mBuilder.toString();
}

// 获取验证码
public String getCode() {
    return code;
}

// 生成干扰线
private void drawLine(Canvas canvas, Paint paint) {
    int color = randomColor();
    int startX = mRandom.nextInt(DEFAULT_WIDTH);
    int startY = mRandom.nextInt(DEFAULT_HEIGHT);
    int stopX = mRandom.nextInt(DEFAULT_WIDTH);
    int stopY = mRandom.nextInt(DEFAULT_HEIGHT);
    paint.setStrokeWidth(1);
    paint.setColor(color);
    canvas.drawLine(startX, startY, stopX, stopY, paint);
}

// 随机颜色
private int randomColor() {
    mBuilder.delete(0, mBuilder.length()); // 使用之前首先清空内容

    String haxString;
    for (int i = 0; i < 3; i++) {
        haxString = Integer.toHexString(mRandom.nextInt(0xFF));
        if (haxString.length() == 1) {
            haxString = "0" + haxString;
        }

        mBuilder.append(haxString);
    }

    return Color.parseColor("#" + mBuilder.toString());
}

// 随机文本样式
private void randomTextStyle(Paint paint) {
    int color = randomColor();
    paint.setColor(color);
    paint.setFakeBoldText(mRandom.nextBoolean()); // true为粗体，false为非粗体
    float skewX = mRandom.nextInt(11) / 10;
    skewX = mRandom.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
}

// 随机间距
private void randomPadding() {
    mPaddingLeft += BASE_PADDING_LEFT + mRandom.nextInt(RANGE_PADDING_LEFT);
    mPaddingTop = BASE_PADDING_TOP + mRandom.nextInt(RANGE_PADDING_TOP);
}

}