
首先是要获取 随机的四个字母组合,我这里是将26个字母存储到一个数组中,然后随机生成4个下标值,取这四个下标值对应的字母作为验证码。
public class RandomChars {char[] chars;public RandomChars() {chars = new char[26];for (int i = 0; i < 26; i++) {chars[i] = (char) (i + 65);}}public char[] get4Chars() {char[] rlt = new char[4];for (int i = 0; i < rlt.length; i++) {int randomIndex = (int) (Math.random() * 26);rlt[i] = chars[randomIndex];}return rlt;}}自定义一个CodeView进行验证码的绘制,主要在onDraw方法中操作,学艺不精,还不能好好在onMeasure中控制大小位置等。float unitWidth = (float) getWidth() / (float) chars.length;for (int i = 0; i < chars.length; i++) {String str = chars[i] + "";textPaint.getTextBounds(str, 0, str.length(), mRect);resetColor();int angel = (int) (Math.random()*(8-(-8)+1)+(-8));canvas.rotate(angel);//旋转字母,随机角度canvas.drawText(str, i * unitWidth + 5, getHeight() / 2 - mRect.centerY(), textPaint);/** * 很关键,旋转 */canvas.save();//保存状态canvas.restore();//恢复}/** * 重新设置随机颜色 */private void resetColor() {int r = (int) (Math.random() * 230 - 30);int g = (int) (Math.random() * 230 - 30);int b = (int) (Math.random() * 230 - 30);textPaint.setColor(Color.rgb(r, g, b));}设置该控件并传入四个字符就ok了,验证是否输入正确的时候,考虑到大小写问题,所以将输入的字母全部转换成大写,一般都是不区分大小写。submit.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {String inputStr = input.getText().toString();inputStr = inputStr.toUpperCase();str = str.toUpperCase();if (str.equals(inputStr)) {Toast.makeText(MainActivity.this, "输入正确", Toast.LENGTH_SHORT).show();}else{Toast.makeText(MainActivity.this, "验证码输入错误", Toast.LENGTH_SHORT).show();char[] getchar = randomChars.get4Chars();str = new String(getchar);codeView.setChars(getchar);}}});感觉还有挺多不足的地方,以后继续改进吧!