android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，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，activity_main.xml:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >    <RelativeLayout        android:layout_width="match_parent"        android:layout_height="50dp"        android:background="@color/main_color_white" >        <TextView            android:id="@+id/tv_title"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_centerInParent="true"            android:text="找回密码"            android:textColor="@color/loan_butBackground"            android:textSize="20sp" />    </RelativeLayout>    <LinearLayout        android:layout_width="match_parent"        android:layout_height="40dp"        android:layout_marginTop="30dp"        android:orientation="vertical"         android:layout_marginLeft="15dp"        android:layout_marginRight="15dp"        android:background="@drawable/security_code_bg">                <LinearLayout            android:layout_width="match_parent"            android:layout_height="match_parent"            android:gravity="center_vertical"            android:orientation="horizontal" >            <TextView                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:layout_marginLeft="20dp"                android:layout_marginRight="20dp"                android:text="中国+86"                android:textColor="#A2CD5A"                android:textSize="16sp" />            <View                android:layout_width="0.1dp"                android:layout_height="match_parent"                android:background="@color/loan_butBackground" />            <EditText                android:id="@+id/et_forgetPass_PhoneNum"                android:layout_width="match_parent"                android:layout_height="wrap_content"                android:layout_marginLeft="20dp"                android:background="@null"                android:digits="0123456789"                android:hint="请填入您的手机号"                android:inputType="number"                android:maxLength="11"                android:textSize="16sp" />        </LinearLayout>    </LinearLayout>       <LinearLayout                android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginLeft="15dp"        android:layout_marginRight="15dp"        android:layout_marginTop="20dp"        android:orientation="horizontal" >        <LinearLayout            android:layout_width="wrap_content"            android:layout_height="40dp"            android:background="@drawable/security_code_bg" >            <EditText                android:id="@+id/et_phoneCodes"                android:layout_width="match_parent"                android:layout_height="match_parent"                android:layout_marginLeft="10dp"                android:layout_marginRight="10dp"                android:background="@null"                android:hint="请输入右侧验证码" />        </LinearLayout>        <ImageView            android:id="@+id/iv_showCode"            android:layout_width="100dp"            android:layout_marginLeft="10dp"            android:layout_height="match_parent" />            </LinearLayout>    <Button        android:id="@+id/but_forgetpass_toSetCodes"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_margin="20dp"        android:background="@drawable/buttonshape"        android:text="提交验证码"        android:textColor="@color/main_color_white" /></LinearLayout>

3,在主界面生成随机数，校验验证码MainActivity.java:

public class MainActivity extends Activity implements OnClickListener {    public static final String TAG = MainActivity.class.getName();    private ImageView iv_showCode;    private EditText et_phoneCode;    private EditText et_phoneNum;    //产生的验证码    private String realCode;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        et_phoneCode = (EditText) findViewById(R.id.et_phoneCodes);        Button but_toSetCode = (Button) findViewById(R.id.but_forgetpass_toSetCodes);        but_toSetCode.setOnClickListener(this);        iv_showCode = (ImageView) findViewById(R.id.iv_showCode);        //将验证码用图片的形式显示出来        iv_showCode.setImageBitmap(Code.getInstance().createBitmap());        realCode = Code.getInstance().getCode().toLowerCase();        iv_showCode.setOnClickListener(this);    }    @Override    public void onClick(View v) {        switch (v.getId()) {            case R.id.iv_showCode:                iv_showCode.setImageBitmap(Code.getInstance().createBitmap());                realCode = Code.getInstance().getCode().toLowerCase();                Log.v(TAG,"realCode"+realCode);                break;            case R.id.but_forgetpass_toSetCodes:                String phoneCode = et_phoneCode.getText().toString().toLowerCase();                String msg = "生成的验证码："+realCode+"输入的验证码:"+phoneCode;                Toast.makeText(MainActivity.this,msg,Toast.LENGTH_LONG).show();                if (phoneCode.equals(realCode)) {                    Toast.makeText(MainActivity.this, phoneCode + "验证码正确", Toast.LENGTH_SHORT).show();                } else {                    Toast.makeText(MainActivity.this, phoneCode + "验证码错误", Toast.LENGTH_SHORT).show();                }                break;        }    }}

至此，基本功能已实现，如有疑问欢迎留言或加群讨论：196615382，如需源码，点击下载。。。