android随机功能,android端实现验证码随机生成功能

本文实例为大家分享了android端生成随机验证码的具体代码，供大家参考，具体内容如下

package com.nobeg.util;

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 Code {

private static final char[] CHARS = {

'2', '3', '4', '5', '6', '7', '8', '9',

'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'j', 'k', 'l', '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

private static final int DEFAULT_CODE_LENGTH = 3;

private static final int DEFAULT_FONT_SIZE = 25;

private static final int DEFAULT_LINE_NUMBER = 2;

private static final int BASE_PADDING_LEFT = 5, RANGE_PADDING_LEFT = 15, BASE_PADDING_TOP = 15, RANGE_PADDING_TOP = 20;

private static final int DEFAULT_WIDTH = 60, 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.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;

}

//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();

}

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);

}

}

java代码：

yanzhengma_img = (ImageView) findViewById(R.id.yanzhengma_img);

yanzhengma_huan = (Button) findViewById(R.id.yanzhengma_huan);

yanzhengma_val = (EditText) findViewById(R.id.yanzhengma_val);

yanzhengma_img.setImageBitmap(code.getInstance().createBitmap());

System.out.println("验证码："+code.getInstance().getCode());

yanzhengma_huan.setOnClickListener(new View.OnClickListener() {

public void onClick(View v) {

yanzhengma_img.setImageBitmap(code.getInstance().createBitmap());

System.out.println("验证码："+code.getInstance().getCode());

}

});

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。