<?xml version="1.0" encoding="utf-8"?>
<resources>
 <declare-styleable name="MyCustomView">
  <attr name="mborder_color" format="color"></attr>
  <attr name="mborder_width" format="dimension"></attr>
  <attr name="msrc" format="reference"></attr>
 </declare-styleable>
</resources>

 TypedArray type = context.obtainStyledAttributes(attrs, R.styleable.MyCustomView);
 mBorderColor = type.getColor(R.styleable.MyCustomView_mborder_color,0);
 mDrawable = type.getDrawable(R.styleable.MyCustomView_msrc);

 //将获得的 Drawable 转换成 Bitmap
 BitmapDrawable bitmapDrawable = (BitmapDrawable) mDrawable;
 mBitmap = bitmapDrawable.getBitmap();

 mBorderWidth = type.getDimensionPixelSize(R.styleable.MyCustomView_mborder_width, 2);

  mSrcBitmap = Bitmap.createScaledBitmap(mBitmap, mWidth, mHeight, false);
  mShader = new BitmapShader(mSrcBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
  mPaint = new Paint();
  mPaint.setShader(mShader);
  mRadius = (mWidth - mBorderWidth * 2 - 4) / 2;
  mCircleX = (mWidth) / 2;
  mCircleY = (mHeight) / 2;

  mBorderPaint = new Paint();
  mBorderPaint.setStyle(Paint.Style.STROKE);
  mBorderPaint.setStrokeWidth(mBorderWidth);
  mBorderPaint.setColor(mBorderColor);
  mBorderPaint.setStrokeCap(Paint.Cap.ROUND);

 @Override
 protected void onDraw(Canvas canvas) {
  super.onDraw(canvas);
  canvas.drawCircle(mCircleX, mCircleY, mRadius, mPaint);
  canvas.drawCircle(mCircleX, mCircleY, mRadius, mBorderPaint);
 }

 <com.example.hwaphon.patheffecttest.MyView
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_marginBottom="16dp"
   android:layout_marginRight="8dp"
   app:mborder_color="@android:color/holo_green_light"
   app:mborder_width="4dp"
   app:msrc="@drawable/myview_test"/>

xmlns:app=[url=http://schemas.android.com/apk/res-auto]http://schemas.android.com/apk/res-auto[/url]

package com.example.hwaphon.patheffecttest;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.View;

/**
 * Created by Hwaphon on 2016/5/12.
 */
public class MyView extends View {

 private Bitmap mBitmap;
 private Drawable mDrawable;
 private Bitmap mSrcBitmap;

 private BitmapShader mShader;
 private Paint mPaint;

 private int mWidth, mHeight;

 private int mRadius;
 private int mCircleX, mCircleY;

 private int mBorderColor;
 private Paint mBorderPaint;
 private int mBorderWidth;

 public MyView(Context context) {
  this(context, null);
 }

 public MyView(Context context, AttributeSet attrs) {
  super(context, attrs);
  TypedArray type = context.obtainStyledAttributes(attrs, R.styleable.MyCustomView);
  mBorderColor = type.getColor(R.styleable.MyCustomView_mborder_color,0);
  mDrawable = type.getDrawable(R.styleable.MyCustomView_msrc);

  //将获得的 Drawable 转换成 Bitmap
  BitmapDrawable bitmapDrawable = (BitmapDrawable) mDrawable;
  mBitmap = bitmapDrawable.getBitmap();

  mBorderWidth = type.getDimensionPixelSize(R.styleable.MyCustomView_mborder_width, 2);
 }

 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  super.onMeasure(widthMeasureSpec, heightMeasureSpec);
  mWidth = measureWidth(widthMeasureSpec);
  mHeight = measureHeight(heightMeasureSpec);
  int temp = mWidth > mHeight ? mHeight : mWidth;
  mWidth = mHeight = temp;
  initView();
  setMeasuredDimension(mWidth, mHeight);
 }

 private int measureHeight(int heightMeasureSpec) {
  int size = MeasureSpec.getSize(heightMeasureSpec);
  int sizeMode = MeasureSpec.getMode(heightMeasureSpec);
  int result = 0;
  if (sizeMode == MeasureSpec.EXACTLY) {
   result = size;
  } else {
   result = 200;
   if (sizeMode == MeasureSpec.AT_MOST) {
    result = Math.min(result, size);
   }
  }
  return result;
 }

 private int measureWidth(int widthMeasureSpec) {
  int size = MeasureSpec.getSize(widthMeasureSpec);
  int sizeMode = MeasureSpec.getMode(widthMeasureSpec);
  int result = 0;
  if (sizeMode == MeasureSpec.EXACTLY) {
   result = size;
  } else {
   result = 200;
   if (sizeMode == MeasureSpec.AT_MOST) {
    result = Math.min(result, size);
   }
  }
  return result;
 }

 private void initView() {

  mSrcBitmap = Bitmap.createScaledBitmap(mBitmap, mWidth, mHeight, false);
  mShader = new BitmapShader(mSrcBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
  mPaint = new Paint();
  mPaint.setShader(mShader);
  mRadius = (mWidth - mBorderWidth * 2) / 2;
  mCircleX = (mWidth) / 2;
  mCircleY = (mHeight) / 2;

  mBorderPaint = new Paint();
  mBorderPaint.setStyle(Paint.Style.STROKE);
  mBorderPaint.setStrokeWidth(mBorderWidth);
  mBorderPaint.setColor(mBorderColor);
  mBorderPaint.setStrokeJoin(Paint.Join.ROUND);
  mBorderPaint.setStrokeCap(Paint.Cap.ROUND);
 }

 @Override
 protected void onDraw(Canvas canvas) {
  super.onDraw(canvas);
  canvas.drawCircle(mCircleX, mCircleY, mRadius, mPaint);
  canvas.drawCircle(mCircleX, mCircleY, mRadius, mBorderPaint);
 }
}