Android仿支付宝支付密码输入框

package com.jackie.alipay.password; 
 
import android.annotation.TargetApi; 
import android.content.Context; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.os.Build; 
import android.util.AttributeSet; 
import android.widget.EditText; 
import android.widget.Toast; 
 
/** 
 * Created by Administrator on 2016/10/31. 
 */ 
 
public class PasswordView extends EditText { 
 private Paint mBorderPaint; //外框画笔 
 private Paint mLinePaint; //线的画笔 
 private Paint mPasswordPaint; //密码画笔 
 private int mPasswordTextLength; //输入密码的长度 
 private int mWidth; 
 private int mHeight; 
 
 private static final int PASSWORD_LENGTH = 6;//密码的长度 
 private static final int PASSWORD_RADIUS = 15; 
 
 public PasswordView(Context context) { 
 this(context, null); 
 } 
 
 public PasswordView(Context context, AttributeSet attrs) { 
 this(context, attrs, 0); 
 } 
 
 public PasswordView(Context context, AttributeSet attrs, int defStyleAttr) { 
 super(context, attrs, defStyleAttr); 
 
 initView(); 
 } 
 
 private void initView() { 
 setFocusable(true); 
 
 mBorderPaint = new Paint(); 
 mBorderPaint.setStrokeWidth(8); 
 mBorderPaint.setColor(Color.WHITE); 
 mBorderPaint.setStyle(Paint.Style.FILL); 
 
 mLinePaint = new Paint(); 
 mLinePaint.setColor(Color.parseColor("#838B8B")); 
 mLinePaint.setStrokeWidth(4); 
 
 mPasswordPaint = new Paint(); 
 mPasswordPaint.setColor(Color.BLACK); 
 mPasswordPaint.setStrokeWidth(12); 
 } 
 
 @Override 
 protected void onDraw(Canvas canvas) { 
 super.onDraw(canvas); 
 
 mWidth = getMeasuredWidth(); 
 mHeight = getMeasuredHeight(); 
 
 drawRoundRect(canvas); 
 drawLine(canvas); 
 drawPassword(canvas); 
 } 
 
 /** 
 * 绘制圆角矩形背景 
 * @param canvas 
 */ 
 @TargetApi(Build.VERSION_CODES.LOLLIPOP) 
 private void drawRoundRect(Canvas canvas) { 
 canvas.drawRoundRect(0, 0, mWidth, mHeight, 12, 12, mBorderPaint); 
 
 } 
 
 /** 
 * 绘制分割线 
 * @param canvas 
 */ 
 private void drawLine(Canvas canvas) { 
 for (int i = 1; i < PASSWORD_LENGTH; i++) { 
  float x = mWidth * i / PASSWORD_LENGTH; 
  canvas.drawLine(x, 12, x, mHeight - 12, mLinePaint); 
 } 
 } 
 
 /** 
 * 绘制密码 
 * @param canvas 
 */ 
 private void drawPassword(Canvas canvas) { 
 float cx, cy = mHeight / 2; 
 float half = mWidth / PASSWORD_LENGTH / 2; 
 for (int i = 0; i < mPasswordTextLength; i++) { 
  cx = mWidth * i / PASSWORD_LENGTH + half; 
  canvas.drawCircle(cx, cy, PASSWORD_RADIUS, mPasswordPaint); 
 } 
 } 
 
 @Override 
 protected void onTextChanged(CharSequence text, int start, int lengthBefore, int lengthAfter) { 
 super.onTextChanged(text, start, lengthBefore, lengthAfter); 
 
 mPasswordTextLength = text.toString().length(); 
 
 if (mPasswordTextLength == PASSWORD_LENGTH) { 
  Toast.makeText(getContext(), "您设置的密码为: " + text, Toast.LENGTH_SHORT).show();; 
 } 
 
 invalidate(); 
 } 
 
 
 public void reset(){ 
 setText(""); 
 invalidate(); 
 } 
}