android图形验证码

废话不多说上效果图：

给上activity_main.xml布局代码：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="${relativePackage}.${activityClass}" >

    <LinearLayout 
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginLeft="10dp"
        android:orientation="vertical">
        <ImageView 
            android:id="@+id/image"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:src="@drawable/ic_launcher"/>
        <EditText 
            android:id="@+id/et"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:hint="输入验证码"/>
        <Button 
            android:id="@+id/btn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:text="获得验证码"/>
        <Button 
            android:id="@+id/btn_submit"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:text="提交"/>
    </LinearLayout>

</RelativeLayout>

再上mainactivity代码：

package com.example.codedemo;

import android.app.Activity;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

	private ImageView image;
	private EditText et;
	private Button btn,submit;
	private String codeStr;
	private CodeUtils codeUtils;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		initView();
		
	}

	private void initView() {
		image = (ImageView) findViewById(R.id.image);
		et = (EditText) findViewById(R.id.et);
		btn = (Button) findViewById(R.id.btn);
		submit = (Button) findViewById(R.id.btn_submit);
		btn.setOnClickListener(this);
		submit.setOnClickListener(this);
		
	}

	@Override
	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.btn:
			codeUtils = CodeUtils.getInstance();
			Bitmap bitmap = codeUtils.createBitmap();
			image.setImageBitmap(bitmap);
			
			break;
		case R.id.btn_submit:
			codeStr = et.getText().toString().trim();
			Log.e("codeStr", codeStr);
			if (null == codeStr || TextUtils.isEmpty(codeStr)) {
				Toast.makeText(this, "请输入验证码", 0).show();
				return;
			}
			String code = codeUtils.getCode();
			Log.e("code", code);
			if (code.equalsIgnoreCase(codeStr)) {
				Toast.makeText(this, "验证码正确", 0).show();
			} else {
				Toast.makeText(this, "验证码错误", 0).show();
			}
			break;
		default:
			break;
		}
		
	}
}

最后附上CodeUtils代码：

package com.example.codedemo;

import android.graphics.Bitmap;  
import android.graphics.Bitmap.Config;  
import android.graphics.Canvas;  
import android.graphics.Color;  
import android.graphics.Paint;  
  
import java.util.Random;  
  
/** 
 * Created by yao 
 * 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();  
  
    //Default Settings  
    private static final int DEFAULT_CODE_LENGTH = 6;//验证码的长度  这里是6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 = 30;//左边距范围值  
    private static final int BASE_PADDING_TOP = 70;//上边距  
    private static final int RANGE_PADDING_TOP = 15;//上边距范围值  
    private static final int DEFAULT_WIDTH = 300;//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  

	private String code;
  
    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);  
  
        code = createCode();  
  
        canvas.drawColor(Color.rgb(DEFAULT_COLOR, DEFAULT_COLOR, DEFAULT_COLOR));  
        Paint paint = new Paint();  
        paint.setTextSize(DEFAULT_FONT_SIZE);  
  
        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;  
    }  
    /**
     * 得到图片中的验证码字符串
     * @return 
     */
    public String getCode() {
    	return code;
    }
  
    //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)]);  
        }  
  
        return mBuilder.toString();  
    }  
  
    //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);  
    }  
}  

其中，在Default Settings中可以设置验证码图形的大小，验证码的长度，内边距，随机距离等可以根据需要进行调整。