圆形图

自定义圆形图控件

public class RoundImageView 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 RoundImageView(Context context) {
        super(context);
      }

      public RoundImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
      }

      public RoundImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        super.setScaleType(SCALE_TYPE);

        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);

        mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_border_width, DEFAULT_BORDER_WIDTH);
        mBorderColor = a.getColor(R.styleable.CircleImageView_border_color, DEFAULT_BORDER_COLOR);

        a.recycle();

        mReady = true;

        if (mSetupPending) {
          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;
        }

        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();

        mBorderRect.set(0, 0, getWidth(), getHeight());
        mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2, (mBorderRect.width() - mBorderWidth) / 2);

        mDrawableRect.set(mBorderWidth, mBorderWidth, mBorderRect.width() - mBorderWidth, mBorderRect.height() - mBorderWidth);
        mDrawableRadius = Math.min(mDrawableRect.height() / 2, mDrawableRect.width() / 2);

        updateShaderMatrix();
        invalidate();
      }

      private void updateShaderMatrix() {
        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);
      }

    }

需要在values文件夹下创建attr.xml

<resources>
    <declare-styleable name="CircleImageView">
        <attr name="border_width" format="dimension" />
        <attr name="border_color" format="color" />
    declare-styleable>
resources>

布局中使用该控件即可

<com.example.androidtest.RoundImageView 
    android:id="@+id/img"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerVertical="true"
    />

程序中给该控件设置图片

img=(RoundImageView) findViewById(R.id.img);
        img.setImageResource(R.drawable.cardetails_img_xingshi);