首先创建一个继承ImageView的抽象类MaskedImage。让他重写onDraw方法。代码如下

public abstract class MaskedImage extends ImageView {	private static final Xfermode MASK_XFERMODE;	private Bitmap mask;	private Paint paint;	static {		PorterDuff.Mode localMode = PorterDuff.Mode.DST_IN;		MASK_XFERMODE = new PorterDuffXfermode(localMode);	}	public MaskedImage(Context paramContext) {		super(paramContext);	}	public MaskedImage(Context paramContext, AttributeSet paramAttributeSet) {		super(paramContext, paramAttributeSet);	}	public MaskedImage(Context paramContext, AttributeSet paramAttributeSet, int paramInt) {		super(paramContext, paramAttributeSet, paramInt);	}	public abstract Bitmap createMask();	protected void onDraw(Canvas paramCanvas) {		Drawable localDrawable = getDrawable();		if (localDrawable == null)			return;		try {			if (this.paint == null) {				Paint localPaint1 = new Paint();				this.paint = localPaint1;				this.paint.setFilterBitmap(false);				Paint localPaint2 = this.paint;				Xfermode localXfermode1 = MASK_XFERMODE;				@SuppressWarnings("unused")				Xfermode localXfermode2 = localPaint2.setXfermode(localXfermode1);			}			float f1 = getWidth();			float f2 = getHeight();			int i = paramCanvas.saveLayer(0.0F, 0.0F, f1, f2, null, 31);			int j = getWidth();			int k = getHeight();			localDrawable.setBounds(0, 0, j, k);			localDrawable.draw(paramCanvas);			if ((this.mask == null) || (this.mask.isRecycled())) {				Bitmap localBitmap1 = createMask();				this.mask = localBitmap1;			}			Bitmap localBitmap2 = this.mask;			Paint localPaint3 = this.paint;			paramCanvas.drawBitmap(localBitmap2, 0.0F, 0.0F, localPaint3);			paramCanvas.restoreToCount(i);			return;		} catch (Exception localException) {			StringBuilder localStringBuilder = new StringBuilder()					.append("Attempting to draw with recycled bitmap. View ID = ");			System.out.println("localStringBuilder=="+localStringBuilder);		}	}}

然后新建一个类CircularImage继承MaskedImage。代码如下：

public class CircularImage extends MaskedImage {	public CircularImage(Context paramContext) {		super(paramContext);	}	public CircularImage(Context paramContext, AttributeSet paramAttributeSet) {		super(paramContext, paramAttributeSet);	}	public CircularImage(Context paramContext, AttributeSet paramAttributeSet, int paramInt) {		super(paramContext, paramAttributeSet, paramInt);	}	public Bitmap createMask() {		int i = getWidth();		int j = getHeight();		Bitmap.Config localConfig = Bitmap.Config.ARGB_8888;		Bitmap localBitmap = Bitmap.createBitmap(i, j, localConfig);		Canvas localCanvas = new Canvas(localBitmap);		Paint localPaint = new Paint(1);		localPaint.setColor(-16777216);		float f1 = getWidth();		float f2 = getHeight();		RectF localRectF = new RectF(0.0F, 0.0F, f1, f2);		localCanvas.drawOval(localRectF, localPaint);		return localBitmap;	}}

新建一个MainActivity，代码如下：

public class MainActivity extends Activity {	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.activity_main);				CircularImage cover_user_photo = (CircularImage) findViewById(R.id.cover_user_photo);		cover_user_photo.setImageResource(R.drawable.face);	}}

其XML布局文件为：

(转)圆形头像制作