Android随机生成验证码.pdf-资料库

Android随机生成验证码随机生成验证码 Android随机生成验证码,Android利用随机数绘制不规则的验证码，加强用户登录或者注册的安全性。具体思路如下：在一块固定宽高的画布上，画上固定个数的随机数字和字母，再画上固定条数的干扰线随机数和干扰线的颜色随机生成，随机数的样式随机生成。界面效果如下： 1、生成随机数代码，、生成随机数代码，Code.java: public class Code { //随机数数组 private static final char[] CHARS = { '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'j', 'k', 'm', 'n', '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', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' }; private static Code bmpCode; public static Code getInstance() { if(bmpCode == null) bmpCode = new Code(); return bmpCode; } //default settings //验证码默认随机数的个数 private static final int DEFAULT_CODE_LENGTH = 4;

//默认字体大小 private static final int DEFAULT_FONT_SIZE = 25; //默认线条的条数 private static final int DEFAULT_LINE_NUMBER = 5; //padding值 private static final int BASE_PADDING_LEFT = 10, RANGE_PADDING_LEFT = 15, BASE_PADDING_TOP = 15, RANGE_PADDING_TOP = 20; //验证码的默认宽高 private static final int DEFAULT_WIDTH = 100, DEFAULT_HEIGHT = 40; //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(); //验证码图片 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.setAntiAlias(true); paint.setTextSize(font_size); //画验证码 for (int i = 0; i < code.length(); i++) { randomTextStyle(paint); randomPadding(); c.drawText(code.charAt(i) + "", padding_left, padding_top, paint); } //画线条 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; } //生成验证码 private String createCode() { StringBuilder buffer = new StringBuilder(); for (int i = 0; i < codeLength; i++) { buffer.append(CHARS[random.nextInt(CHARS.length)]); } return buffer.toString(); } //画干扰线 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); } //生成随机颜色 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); } //随机生成文字样式，颜色，粗细，倾斜度 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 } //随机生成padding值 private void randomPadding() { padding_left += base_padding_left + random.nextInt(range_padding_left); padding_top = base_padding_top + random.nextInt(range_padding_top); } } 2、编写布局文件，、编写布局文件，activity_main.xml:

android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center_vertical" android:orientation="horizontal" >

资料库

Android随机生成验证码.pdf

相关推荐

开发技术

热门标签

最新资料