1.生成验证码

package com.medees.dazhima_android;

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;

import java.util.Random;

/**
 *
 * Created by root on 14-7-10.
 *
 * 绘制注册界面验证码
 *
 */
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;
    }

    private static final int DEFAULT_CODE_LENGTH = 4;
    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;

    private int width=DEFAULT_WIDTH,height=DEFAULT_HEIGHT;

    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, Bitmap.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);
    }
}

2.验证过程：

package com.medees.dazhima_android.activity;

import android.content.Intent;
import android.os.Bundle;

import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarActivity;
import android.text.TextUtils;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;
import com.medees.dazhima_android.Code;
import com.medees.dazhima_android.MainActivity;
import com.medees.dazhima_android.R;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 *
 * Created by root on 14-7-10.
 *
 * 用户注册界面
 *
 */



public class RegisterActivity extends ActionBarActivity {

    EditText    editText_register_email;
    EditText    editText_register_name;
    EditText    editText_register_password;
    EditText    editText_register_password_agin;
    EditText    editText_register_code;
    ImageView   imageView_register_yanzhengma;
    ImageView   imageView_register_yanzhengma_refresh;
    Button      button_register;

    String      register_email;
    String      register_name;
    String      register_password;
    String      register_password_agin;
    String      register_code;

    Code code;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.register);
        init();
        imageView_register_yanzhengma.setOnClickListener( new Yanzhengma_Image_OnClickLister());
        imageView_register_yanzhengma_refresh.setOnClickListener(new Yanzhengma_Image_OnClickLister());
        button_register.setOnClickListener(new Register_OnClickLister());
        ActionBar actionBar=getSupportActionBar();
        actionBar.setDisplayHomeAsUpEnabled(true);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        MenuInflater menuInflater=getMenuInflater();
        menuInflater.inflate(R.menu.register_actionbar,menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()){
            case R.id.home:{
                finish();
                Intent intent=new Intent(RegisterActivity.this, MainActivity.class);
                startActivity(intent);
            }return true;
            case R.id.register:
                 new Register_OnClickLister();
        }
        return false;
    }

    private boolean CheckPassWordLength() {
        if (register_password.length()<6)
            return false;
        else
            return true;
    }

    private void InsertRegisterInfo(String register_email, String register_name, String register_password) {

    }

    private boolean CheckCode() {
        if(register_code.equalsIgnoreCase(code.getInstance().getCode()))
            return true;
        else
            return false;
    }

    private boolean CheckPassWordIsEqual() {
        if(register_password.equals(register_password_agin))
            return true;
        else
            return false;
    }

    private boolean CheckInputIsEmpty() {
        if (TextUtils.isEmpty(register_email)||
                TextUtils.isEmpty(register_name)||
                TextUtils.isEmpty(register_password)||
                TextUtils.isEmpty(register_password_agin)||
                TextUtils.isEmpty(register_code))
            return true;

        return false;
    }

    public static boolean CheckIsEmail(String strEmail) {
        String strPattern = "^[a-zA-Z][\\w\\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\\w\\.-]*[a-zA-Z0-9]\\.[a-zA-Z][a-zA-Z\\.]*[a-zA-Z]$";
        Pattern p = Pattern.compile(strPattern);
        Matcher m = p.matcher(strEmail);
        return m.matches();
    }

    private void getRegisterInfo() {
        register_email=editText_register_email.getText().toString();
        register_name=editText_register_name.getText().toString();
        register_password=editText_register_password.getText().toString();
        register_password_agin=editText_register_password_agin.getText().toString();
        register_code=editText_register_code.getText().toString();
    }

    private void init() {
        editText_register_email=(EditText)findViewById(R.id.registerActivity_email);
        editText_register_name=(EditText)findViewById(R.id.registerActivity_name);
        editText_register_password=(EditText)findViewById(R.id.registerActivity_password);
        editText_register_password_agin=(EditText)findViewById(R.id.registerActivity_rePassword);
        editText_register_code=(EditText)findViewById(R.id.register_yanzhengma_code);
        imageView_register_yanzhengma=(ImageView)findViewById(R.id.register_yanzhengma_image);
        imageView_register_yanzhengma_refresh=(ImageView)findViewById(R.id.register_yanzhengma_refresh);
        button_register=(Button)findViewById(R.id.register_button);
        imageView_register_yanzhengma.setImageBitmap(code.getInstance().createBitmap());
        System.out.println("验证码:" + code.getInstance().getCode());
    }

    private class Yanzhengma_Image_OnClickLister implements View.OnClickListener {
        @Override
        public void onClick(View v) {
            imageView_register_yanzhengma.setImageBitmap(code.getInstance().createBitmap());
            System.out.println("验证码:"+code.getInstance().getCode());
        }
    }

    private class Register_OnClickLister implements View.OnClickListener {
        @Override
        public void onClick(View v) {
            getRegisterInfo();
            if(CheckInputIsEmpty()){
                Toast.makeText(RegisterActivity.this,"不能为空!",Toast.LENGTH_SHORT).show();
            }

            else {
                if (CheckIsEmail(register_email)) {
                    if (CheckPassWordLength()) {
                        if (CheckPassWordIsEqual()) {
                            if (CheckCode()) {
                                Toast.makeText(RegisterActivity.this, "注册成功!", Toast.LENGTH_SHORT).show();
                                InsertRegisterInfo(register_email, register_name, register_password);
                            } else
                                Toast.makeText(RegisterActivity.this, "验证码输入错误,请您重新输入!", Toast.LENGTH_SHORT).show();
                        } else {
                            Toast.makeText(RegisterActivity.this, "两次输入的密码不相同,请您重新输入!", Toast.LENGTH_SHORT).show();
                        }
                    } else {
                        Toast.makeText(RegisterActivity.this, "密码必须大于6个字符!", Toast.LENGTH_SHORT).show();
                    }
                }
                else
                    Toast.makeText(RegisterActivity.this, "请输入正确的邮箱!", Toast.LENGTH_SHORT).show();
            }
        }
    }
}

安卓验证码的生成与验证