CircleImg.java自定义圆形图

感谢源码制作者：https://github.com/hdodenhof/CircleImageView

有些报错可能是最低版本写的太小   报错可以百度解决掉的。

public class CircleImg extends ImageView {
  private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;

     private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;
     private static final int COLORDRAWABLE_DIMENSION = 1;

     private static final int DEFAULT_BORDER_WIDTH = 0;
     private static final int DEFAULT_BORDER_COLOR = Color.BLACK;

     private final RectF mDrawableRect = new RectF();
     private final RectF mBorderRect = new RectF();

     private final Matrix mShaderMatrix = new Matrix();
     private final Paint mBitmapPaint = new Paint();
     private final Paint mBorderPaint = new Paint();

     private int mBorderColor = DEFAULT_BORDER_COLOR;
     private int mBorderWidth = DEFAULT_BORDER_WIDTH;

     private Bitmap mBitmap;
     private BitmapShader mBitmapShader;
     private int mBitmapWidth;
     private int mBitmapHeight;

     private float mDrawableRadius;
     private float mBorderRadius;

     private boolean mReady;
     private boolean mSetupPending;
 public CircleImg(Context context) {
         super(context);
     }
     public CircleImg(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }
 public CircleImg(Context context, AttributeSet attrs, int defStyle) {
  super(context, attrs, defStyle);
  super.setScaleType(SCALE_TYPE);
  // TODO Auto-generated constructor stub
  TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle,0);
        a.getDimensionPixelSize(R.styleable.CirclePageIndicator_radius, DEFAULT_BORDER_COLOR);
        a.recycle();
        mReady = true;
         /**
          * 第一次则设置
          */
        
       
 if (mSetupPending) {
            /*
             * 设置完图片之后必定会调用setup方法，其实这个方法就是一个初始化操作而已，
             * 但是在setup的结束地方也调用了invalidate
             */
       setup();
 mSetupPending = false;
   }
           
 }
 
  @Override
     public ScaleType getScaleType() {
         return SCALE_TYPE;
     }
  @Override
     public void setScaleType(ScaleType scaleType) {
         if (scaleType != SCALE_TYPE) {
             throw new IllegalArgumentException(String.format("ScaleType %s not supported.", scaleType));
         }
     }
   @Override
     protected void onDraw(Canvas canvas) {
         if (getDrawable() == null) {
             return;
         }

         canvas.drawCircle(getWidth() / 2, getHeight() / 2, mDrawableRadius, mBitmapPaint);
         canvas.drawCircle(getWidth() / 2, getHeight() / 2, mBorderRadius, mBorderPaint);
     }
  
   @Override
     protected void onSizeChanged(int w, int h, int oldw, int oldh) {
         super.onSizeChanged(w, h, oldw, oldh);
         setup();
     }

     public int getBorderColor() {
         return mBorderColor;
     }

     public void setBorderColor(int borderColor) {
         if (borderColor == mBorderColor) {
             return;
         }

         mBorderColor = borderColor;
         mBorderPaint.setColor(mBorderColor);
         invalidate();
     }

     public int getBorderWidth() {
         return mBorderWidth;
     }

     public void setBorderWidth(int borderWidth) {
         if (borderWidth == mBorderWidth) {
             return;
         }

         mBorderWidth = borderWidth;
         setup();
     }

     @Override
     public void setImageBitmap(Bitmap bm) {
         super.setImageBitmap(bm);
         mBitmap = bm;
         setup();
     }

     @Override
     public void setImageDrawable(Drawable drawable) {
         super.setImageDrawable(drawable);
         mBitmap = getBitmapFromDrawable(drawable);
         setup();
     }

     @Override
     public void setImageResource(int resId) {
         super.setImageResource(resId);
         mBitmap = getBitmapFromDrawable(getDrawable());
         setup();
     }

     private Bitmap getBitmapFromDrawable(Drawable drawable) {
         if (drawable == null) {
             return null;
         }

         if (drawable instanceof BitmapDrawable) {
             return ((BitmapDrawable) drawable).getBitmap();
         }

         try {
             Bitmap bitmap;

             if (drawable instanceof ColorDrawable) {
                 bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);
             } else {
                 bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), BITMAP_CONFIG);
             }

             Canvas canvas = new Canvas(bitmap);
             drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
             drawable.draw(canvas);
             return bitmap;
         } catch (OutOfMemoryError e) {
             return null;
         }
     }
 private void setup() {
        if (!mReady) {
            mSetupPending = true;
            return;
        }
      //当有图片被设置以后才会开始执行下面的方法
        if (mBitmap == null) {
            return;
        }

        mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);

        mBitmapPaint.setAntiAlias(true);
        mBitmapPaint.setShader(mBitmapShader);

        mBorderPaint.setStyle(Paint.Style.STROKE);
        mBorderPaint.setAntiAlias(true);
        mBorderPaint.setColor(mBorderColor);
        mBorderPaint.setStrokeWidth(mBorderWidth);

        mBitmapHeight = mBitmap.getHeight();
        mBitmapWidth = mBitmap.getWidth();
      //整个图像的显示区域：即全部的View大小区域。
        mBorderRect.set(0, 0, getWidth(), getHeight());
      //Border的半径为长宽中取小的那一边，android中drawCircle的半径是内圆的半径，不是外圆的半径。
        mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2, (mBorderRect.width() - mBorderWidth) / 2);
      //图片显示的区域：即View的大小区域减去边界的大小。
        mDrawableRect.set(mBorderWidth, mBorderWidth, mBorderRect.width() - mBorderWidth, mBorderRect.height() - mBorderWidth);
        mDrawableRadius = Math.min(mDrawableRect.height() / 2, mDrawableRect.width() / 2);
        //图片的半径大小取图片小边
        updateShaderMatrix();
        invalidate();
    }
 private void updateShaderMatrix() {
  // TODO Auto-generated method stub
   float scale;
         float dx = 0;
         float dy = 0;

         mShaderMatrix.set(null);

         if (mBitmapWidth * mDrawableRect.height() > mDrawableRect.width() * mBitmapHeight) {
             scale = mDrawableRect.height() / (float) mBitmapHeight;
             dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f;
         } else {
             scale = mDrawableRect.width() / (float) mBitmapWidth;
             dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f;
         }

         mShaderMatrix.setScale(scale, scale);
         mShaderMatrix.postTranslate((int) (dx + 0.5f) + mBorderWidth, (int) (dy + 0.5f) + mBorderWidth);

         mBitmapShader.setLocalMatrix(mShaderMatrix);
     }
}