public class Code {   //隨機數數組  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  //驗證碼默認隨機數的個數  private static final int DEFAULT_CODE_LENGTH = 4;  //默認字體大小  private static final int DEFAULT_FONT_SIZE = 25;  //默認線條的條數  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;  //驗證碼的默認寬高  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();  //驗證碼圖片  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);   //畫驗證碼   for (int i = 0; i < code.length(); i++) {    randomTextStyle(paint);    randomPadding();    c.drawText(code.charAt(i) + "", padding_left, padding_top, paint);   }   //畫線條   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;  }   //生成驗證碼  private String createCode() {   StringBuilder buffer = new StringBuilder();   for (int i = 0; i < codeLength; i++) {    buffer.append(CHARS[random.nextInt(CHARS.length)]);   }   return buffer.toString();  }  //畫干擾線  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);  }  //生成隨機顏色  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);  }  //隨機生成文字樣式，顏色，粗細，傾斜度  private void randomTextStyle(Paint paint) {   int color = randomColor();   paint.setColor(color);   paint.setFakeBoldText(random.nextBoolean()); //true為粗體，false為非粗體   float skewX = random.nextInt(11) / 10;   skewX = random.nextBoolean() ? skewX : -skewX;   paint.setTextSkewX(skewX); //float類型參數，負數表示右斜，整數左斜   //paint.setUnderlineText(true); //true為下劃線，false為非下劃線   //paint.setStrikeThruText(true); //true為刪除線，false為非刪除線  }  //隨機生成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);  } } 

<?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="找回密碼"    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="中國+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="請填入您的手機號"     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="請輸入右側驗證碼" />   </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="提交驗證碼"   android:textColor="@color/main_color_white" />  </LinearLayout> 

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;  //產生的驗證碼  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);   //將驗證碼用圖片的形式顯示出來   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 = "生成的驗證碼："+realCode+"輸入的驗證碼:"+phoneCode;     Toast.makeText(MainActivity.this,msg,Toast.LENGTH_LONG).show();      if (phoneCode.equals(realCode)) {      Toast.makeText(MainActivity.this, phoneCode + "驗證碼正確", Toast.LENGTH_SHORT).show();     } else {      Toast.makeText(MainActivity.this, phoneCode + "驗證碼錯誤", Toast.LENGTH_SHORT).show();     }     break;   }  } }