Android自定义PasswordInputView密码输入

public PasswordInputView(Context context, AttributeSet attr) {
  super(context, attr);
  init(context, attr);
}

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <declare-styleable name="Passwordinputview">
    <attr name="passwordLength" format="integer"/>
    <attr name="borderWidth" format="dimension"/>
    <attr name="borderRadius" format="dimension"/>
    <attr name="borderColor" format="color"/>
    <attr name="passwordWidth" format="dimension"/>
    <attr name="passwordColor" format="color"/>
  </declare-styleable>
</resources>

 private void init(Context context, AttributeSet attr) {
  TypedArray ta = context.obtainStyledAttributes(attr, R.styleable.Passwordinputview);
  try {
   passwordLength = ta.getInt(R.styleable.Passwordinputview_passwordLength, passwordLength);
   borderWidth = ta.getDimensionPixelSize(R.styleable.Passwordinputview_borderWidth, borderWidth);
   borderRadius = ta.getDimensionPixelSize(R.styleable.Passwordinputview_borderRadius, borderRadius);
   borderColor = ta.getColor(R.styleable.Passwordinputview_borderColor, borderColor);
   passwordWidth = ta.getDimensionPixelSize(R.styleable.Passwordinputview_passwordWidth, passwordWidth);
   passwordColor = ta.getColor(R.styleable.Passwordinputview_passwordColor, passwordColor);
  } catch (Exception e) {

  }
  ta.recycle();

  borderPaint = new Paint();
  borderPaint.setAntiAlias(true);
  borderPaint.setColor(borderColor);
  borderPaint.setStrokeWidth(borderWidth);
  borderPaint.setStyle(Paint.Style.FILL); //以填充模式来画，防止原始输入内容显示出来

  passwordPaint = new Paint();
  passwordPaint.setAntiAlias(true);
  passwordPaint.setColor(passwordColor);
  passwordPaint.setStrokeWidth(passwordWidth);
 }

 @Override
 protected void onDraw(Canvas canvas) {
  // TODO Auto-generated method stub
  super.onDraw(canvas);
  int width = getWidth();
  int height = getHeight();

  //画边框
  RectF rect = new RectF(0, 0, width, height);
  borderPaint.setColor(borderColor);
  canvas.drawRoundRect(rect, borderRadius, borderRadius, borderPaint);

  //画内容区域,与上面的borderPaint.setStyle(Paint.Style.FILL)对应, 防止原始输入内容显示出来
  RectF rectContent = new RectF(rect.left + defaultContentMargin, rect.top + defaultContentMargin, rect.right - defaultContentMargin, rect.bottom - defaultContentMargin);
  borderPaint.setColor(Color.WHITE);
  canvas.drawRoundRect(rectContent, borderRadius, borderRadius, borderPaint);

  //画分割线:分割线数量比密码数少1
  borderPaint.setColor(borderColor);
  borderPaint.setStrokeWidth(defaultSplitLineWidth);
  for (int i = 1; i < passwordLength; i++) {
   float x = width * i / passwordLength;
   canvas.drawLine(x, 0, x, height, borderPaint);
  }

  //画密码内容
  float px, py = height / 2;
  float halfWidth = width / passwordLength / 2;
  for (int i = 0; i < textLength; i++) {
   px = width * i / passwordLength + halfWidth;
   canvas.drawCircle(px, py, passwordWidth, passwordPaint);
  }
}

public void setBorderWidth(int borderWidth) {
 this.borderWidth = borderWidth;
 borderPaint.setStrokeWidth(borderWidth);
 postInvalidate();
}