RoundImageView

package org.com.cctest.view;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.NinePatchDrawable;
import android.util.AttributeSet;
import android.widget.ImageView;

import cn.sunease.yujian.R;

/**
 * 圓形ImageView，可設置最多兩個寬度不同且顏色不同的圓形邊框。
 * 設置顏色在xml佈局文件中由自定義屬性配置參數指定
 */
public class RoundImageView extends ImageView {
   private int mBorderThickness = 0;
   private Context mContext;
   private int defaultColor = 0xFFFFFFFF;
   // 如果只有其中一個有值，則只畫一個圓形邊框
   private int mBorderOutsideColor = 0;
   private int mBorderInsideColor = 0;
   // 控件默認長、寬
   private int defaultWidth = 0;
   private int defaultHeight = 0;


   public RoundImageView(Context context) {
      super(context);
      mContext = context;
   }


   public RoundImageView(Context context, AttributeSet attrs) {
      super(context, attrs);
      mContext = context;
      setCustomAttributes(attrs);
   }


   public RoundImageView(Context context, AttributeSet attrs, int defStyle) {
      super(context, attrs, defStyle);
      mContext = context;
      setCustomAttributes(attrs);
   }


   private void setCustomAttributes(AttributeSet attrs) {
      TypedArray a = mContext.obtainStyledAttributes(attrs,R.styleable.roundedimageview);
      mBorderThickness = a.getDimensionPixelSize(R.styleable.roundedimageview_border_thickness, 0);
      mBorderOutsideColor = a.getColor(R.styleable.roundedimageview_border_outside_color,defaultColor);
      mBorderInsideColor = a.getColor(R.styleable.roundedimageview_border_inside_color, defaultColor);
   }


   @Override
   protected void onDraw(Canvas canvas) {
      Drawable drawable = getDrawable() ;
      if (drawable == null) {
         return;
      }
      if (getWidth() == 0 || getHeight() == 0) {
         return;
      }
      this.measure(0, 0);
      if (drawable.getClass() == NinePatchDrawable.class)
         return;
      Bitmap b = ((BitmapDrawable) drawable).getBitmap();
      Bitmap bitmap = b.copy(Config.ARGB_8888, true);
      if (defaultWidth == 0) {
         defaultWidth = getWidth();
      }
      if (defaultHeight == 0) {
         defaultHeight = getHeight();
      }
      int radius = 0;
      if (mBorderInsideColor != defaultColor && mBorderOutsideColor != defaultColor) {// 定義畫兩個邊框，分別爲外圓邊框和內圓邊框
         radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - 2 * mBorderThickness;
         // 畫內圓
         drawCircleBorder(canvas, radius + mBorderThickness / 2,mBorderInsideColor);
         // 畫外圓
         drawCircleBorder(canvas, radius + mBorderThickness + mBorderThickness / 2, mBorderOutsideColor);
      } else if (mBorderInsideColor != defaultColor && mBorderOutsideColor == defaultColor) {// 定義畫一個邊框
         radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness;
         drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderInsideColor);
      } else if (mBorderInsideColor == defaultColor && mBorderOutsideColor != defaultColor) {// 定義畫一個邊框
         radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness;
         drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderOutsideColor);
      } else {// 沒有邊框
         radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2;
      }
      Bitmap roundBitmap = getCroppedRoundBitmap(bitmap, radius);
      canvas.drawBitmap(roundBitmap, defaultWidth / 2 - radius, defaultHeight / 2 - radius, null);
   }


   /**
    * 獲取裁剪後的圓形圖片
    * @param radius半徑
    */
   public Bitmap getCroppedRoundBitmap(Bitmap bmp, int radius) {
      Bitmap scaledSrcBmp;
      int diameter = radius * 2;
      // 爲了防止寬高不相等，造成圓形圖片變形，因此截取長方形中處於中間位置最大的正方形圖片
      int bmpWidth = bmp.getWidth();
      int bmpHeight = bmp.getHeight();
      int squareWidth = 0, squareHeight = 0;
      int x = 0, y = 0;
      Bitmap squareBitmap;
      if (bmpHeight > bmpWidth) {// 高大於寬
         squareWidth = squareHeight = bmpWidth;
         x = 0;
         y = (bmpHeight - bmpWidth) / 2;
         // 截取正方形圖片
         squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth, squareHeight);
      } else if (bmpHeight < bmpWidth) {// 寬大於高
         squareWidth = squareHeight = bmpHeight;
         x = (bmpWidth - bmpHeight) / 2;
         y = 0;
         squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,squareHeight);
      } else {
         squareBitmap = bmp;
      }
      if (squareBitmap.getWidth() != diameter || squareBitmap.getHeight() != diameter) {
         scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter,diameter, true);
      } else {
         scaledSrcBmp = squareBitmap;
      }
      Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),
            scaledSrcBmp.getHeight(),
            Config.ARGB_8888);
      Canvas canvas = new Canvas(output);


      Paint paint = new Paint();
      Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(),scaledSrcBmp.getHeight());


      paint.setAntiAlias(true);
      paint.setFilterBitmap(true);
      paint.setDither(true);
      canvas.drawARGB(0, 0, 0, 0);
      canvas.drawCircle(scaledSrcBmp.getWidth() / 2,
            scaledSrcBmp.getHeight() / 2,
            scaledSrcBmp.getWidth() / 2,
            paint);
      paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
      canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);
      bmp = null;
      squareBitmap = null;
      scaledSrcBmp = null;
      return output;
   }


   /**
    * 邊緣畫圓
    */
   private void drawCircleBorder(Canvas canvas, int radius, int color) {
      Paint paint = new Paint();
      /* 去鋸齒 */
      paint.setAntiAlias(true);
      paint.setFilterBitmap(true);
      paint.setDither(true);
      paint.setColor(color);
      /* 設置paint的　style　爲STROKE：空心 */
      paint.setStyle(Paint.Style.STROKE);
      /* 設置paint的外框寬度 */
      paint.setStrokeWidth(mBorderThickness);
      canvas.drawCircle(defaultWidth / 2, defaultHeight / 2, radius, paint);
   }
}