package com.customview.widget;import android.graphics.Bitmap;import android.graphics.BitmapShader;import android.graphics.Canvas;import android.graphics.ColorFilter;import android.graphics.Paint;import android.graphics.PixelFormat;import android.graphics.Shader;import android.graphics.drawable.Drawable;import android.support.annotation.IntRange;import android.support.annotation.NonNull;import android.support.annotation.Nullable;/** * 自定義Drawable 實現圓形圖片 * Created by hust_twj on 2017/9/26. */public class CircleDrawable extends Drawable {  private Paint mPaint;  private int mWidth; //寬/高，直徑  private Bitmap mBitmap;  public CircleDrawable(Bitmap bitmap) {    this.mBitmap = bitmap;    BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);//著色器 水平和豎直都需要填充滿    mPaint = new Paint();    mPaint.setAntiAlias(true);    mPaint.setShader(bitmapShader);    mWidth = Math.min(mBitmap.getWidth(), mBitmap.getHeight()); //寬高的最小值作為直徑  }  @Override  public void draw(@NonNull Canvas canvas) {    canvas.drawCircle(mWidth/2, mWidth/2, mWidth/2, mPaint); //繪制圓形  }  @Override  public void setAlpha(@IntRange(from = 0, to = 255) int i) {    mPaint.setAlpha(i);  }  @Override  public void setColorFilter(@Nullable ColorFilter colorFilter) {    mPaint.setColorFilter(colorFilter);  }  @Override  public int getOpacity() {    return PixelFormat.TRANSLUCENT; //設置系統默認，讓drawable支持和窗口一樣的透明度  }  //還需要從重寫以下2個方法，返回drawable實際寬高  @Override  public int getIntrinsicWidth() {    return mWidth;  }  @Override  public int getIntrinsicHeight() {    return mWidth;  }}

package com.customview.widget;import android.graphics.Bitmap;import android.graphics.BitmapShader;import android.graphics.Canvas;import android.graphics.ColorFilter;import android.graphics.Paint;import android.graphics.PixelFormat;import android.graphics.RectF;import android.graphics.Shader;import android.graphics.drawable.Drawable;import android.support.annotation.IntRange;import android.support.annotation.NonNull;import android.support.annotation.Nullable;/** * 自定義Drawable 實現圓角圖片 * Created by hust_twj on 2017/9/26. */public class RoundCornerDrawable extends Drawable {  private Paint mPaint;  private RectF rectF;//定義矩形區域  private Bitmap mBitmap;  public RoundCornerDrawable(Bitmap bitmap) {    this.mBitmap = bitmap;    BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);//著色器 水平和豎直都需要填充滿    mPaint = new Paint();    mPaint.setAntiAlias(true);    mPaint.setShader(bitmapShader);    //rectF = new RectF(0, 0, bitmap.getWidth(), bitmap.getHeight());  }  @Override  public void draw(@NonNull Canvas canvas) {    //RectF:圓角矩形區域    canvas.drawRoundRect(new RectF(0, 0, mBitmap.getWidth(), mBitmap.getHeight()),100, 100, mPaint);//rx：x方向上的圓角半徑; ry：y方向上的圓角半徑。  }/*  @Override  public void setBounds(int left, int top, int right, int bottom) {    super.setBounds(left, top, right, bottom);    rectF = new RectF(left, top, right, bottom);  }*/  @Override  public void setAlpha(@IntRange(from = 0, to = 255) int i) {    mPaint.setAlpha(i);  }  @Override  public void setColorFilter(@Nullable ColorFilter colorFilter) {    mPaint.setColorFilter(colorFilter);  }  @Override  public int getOpacity() {    return PixelFormat.TRANSLUCENT; //設置系統默認，讓drawable支持和窗口一樣的透明度  }  //還需要從重寫以下2個方法，返回drawable實際寬高  @Override  public int getIntrinsicWidth() {    return mBitmap.getWidth();  }  @Override  public int getIntrinsicHeight() {    return mBitmap.getHeight();  }}

Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.XXX);imageView.setImageDrawable(new RoundCornerDrawable(bitmap));