Android 自定义输入支付密码的软键盘实例代码

/**
 * 输入数字密码的键盘布局控件。
 */
public class passwordKeyboardView extends KeyboardView implements
    android.inputmethodservice.KeyboardView.onKeyboardActionListener {

  // 用于区分左下角空白的按键
  private static final int KEYCODE_EMPTY = -10;

  privatE int   m@R_801_9421@eBACkgroundColor;
  private Rect   m@R_801_9421@eDrawRect;
  private Drawable m@R_801_9421@eDrawable;

  private IOnKeyboardListener mOnKeyboardListener;

  public passwordKeyboardView(Context context,AttributeSet attrs) {
    super(context,attrs);
    init(context,attrs,0);
  }

  public passwordKeyboardView(Context context,AttributeSet attrs,int defStyleAttr) {
    super(context,defStyleAttr);
    init(context,defStyleAttr);
  }

  private void init(Context context,int defStyleAttr) {
    TypedArray a = context.obtainStyledAttributes(attrs,R.styleable.passwordKeyboardView,defStyleAttr,0);
    m@R_801_9421@eDrawable = a.getDrawable(
        R.styleable.passwordKeyboardView_pkv@R_801_9421@eDrawablE);
    m@R_801_9421@eBACkgroundColor = a.getColor(
        R.styleable.passwordKeyboardView_pkv@R_801_9421@eBACkgroundColor,Color.TRANSPARENT);
    a.recycle();

    // 设置软键盘按键的布局
    Keyboard keyboard = new Keyboard(context,R.xml.keyboard_number_password);
    setKeyboard(keyboard);

    setEnabled(true);
    setPreviewEnabled(false);
    setOnKeyboardActionListener(this);
  }

  @Override
  public void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    // 遍历所有的按键
    List<Keyboard.Key> keys = getKeyboard().getKeys();
    for (Keyboard.Key key : keys) {
      // 如果是左下角空白的按键，重画按键的背景
      if (key.codes[0] == KEYCODE_EMPTY) {
        drawKeyBACkground(key,canvas,m@R_801_9421@eBACkgroundColor);
      }
      // 如果是右下角的删除按键，重画背景，并且绘制删除的图标
      else if (key.codes[0] == Keyboard.KEYCODE_Delete) {
        drawKeyBACkground(key,m@R_801_9421@eBACkgroundColor);
        draw@R_801_9421@eButton(key,canvas);
      }
    }
  }

  // 绘制按键的背景
  private void drawKeyBACkground(Keyboard.Key key,Canvas canvas,int color) {
    ColorDrawable drawable = new ColorDrawable(color);
    drawable.setBounds(key.x,key.y,key.x + key.width,key.y + key.height);
    drawable.draw(canvas);
  }

  // 绘制删除按键
  private void draw@R_801_9421@eButton(Keyboard.Key key,Canvas canvas) {
    if (m@R_801_9421@eDrawable == null)
      return;

    // 计算删除图标绘制的坐标
    if (m@R_801_9421@eDrawRect == null || m@R_801_9421@eDrawRect.isEmpty()) {
      int intrinsicWidth = m@R_801_9421@eDrawable.geTintrinsicWidth();
      int intrinsicHeight = m@R_801_9421@eDrawable.geTintrinsicHeight();
      int drawWidth = intrinsicWidth;
      int drawHeight = intrinsicHeight;

      // 限制图标的大小，防止图标超出按键
      if (drawWidth > key.width) {
        drawWidth = key.width;
        drawHeight = drawWidth * intrinsicHeight / intrinsicWidth;
      }
      if (drawHeight > key.height) {
        drawHeight = key.height;
        drawWidth = drawHeight * intrinsicWidth / intrinsicHeight;
      }

      // 获取删除图标绘制的坐标
      int left = key.x + (key.width - drawWidth) / 2;
      int top = key.y + (key.height - drawHeight) / 2;
      m@R_801_9421@eDrawRect = new Rect(left,top,left + drawWidth,top + drawHeight);
    }

    // 绘制删除的图标
    if (m@R_801_9421@eDrawRect != null && !m@R_801_9421@eDrawRect.isEmpty()) {
      m@R_801_9421@eDrawable.setBounds(m@R_801_9421@eDrawRect.left,m@R_801_9421@eDrawRect.top,m@R_801_9421@eDrawRect.right,m@R_801_9421@eDrawRect.bottom);
      m@R_801_9421@eDrawable.draw(canvas);
    }
  }

  @Override
  public void onKey(int pri@R_874_11035@Code,int[] keyCodes) {
    // 处理按键的点击事件
    // 点击删除按键
    if (pri@R_874_11035@Code == Keyboard.KEYCODE_Delete) { 
      if (mOnKeyboardListener != null) {
        mOnKeyboardlistener.on@R_801_9421@eKeyEvent();
      }
    }
    // 点击了非左下角按键的其他按键
    else if (pri@R_874_11035@Code != KEYCODE_EMPTY) {
      if (mOnKeyboardListener != null) {
        mOnKeyboardlistener.onInsertKeyEvent(
            Character.toString((char) pri@R_874_11035@CodE));
      }
    }
  }

  @Override
  public void onPress(int pri@R_874_11035@CodE) {

  }

  @Override
  public void onRelease(int pri@R_874_11035@CodE) {

  }

  @Override
  public void ontext(CharSequence text) {

  }

  @Override
  public void swipeLeft() {

  }

  @Override
  public void swipeRight() {

  }

  @Override
  public void swipeDown() {

  }

  @Override
  public void swipeUp() {

  }

  /**
   * 设置键盘的监听事件。
   *
   * @param listener
   *     监听事件
   */
  public void setIOnKeyboardListener(IOnKeyboardListener listener) {
    this.mOnKeyboardListener = listener;
  }

  public interface IOnKeyboardListener {

    void onInsertKeyEvent(String text);

    void on@R_801_9421@eKeyEvent();
  }
}

<declare-styleable name="passwordKeyboardView">
  <attr name="pkv@R_801_9421@eDrawable" format="reference"/>
  <attr name="pkv@R_801_9421@eBACkgroundColor" format="color|reference"/>
</declare-styleable>