自定义Drawable实现圆角图片和圆形图片

浅浅的花香味﹌ 2022-08-21 07:49 245阅读 0赞

**[转载请注明原博客地址：][Link 1]http://write.blog.csdn.net/postedit/51226071**

[**例子源码下载地址：**][Link 2] [**https://github.com/gdutxiaoxu/CustomDrawab**le][Link 2]

**1 自定义圆角图片**

a 继承drawable，重写里面的几个方法

b 通过构造方法传入Bitmap对象，初始化一个BitmapShader，将其传递给我们的画笔

public RoundImageDrawable(Bitmap bitmap) {
    mBitmap = bitmap;
        BitmapShader bitmapShader = new BitmapShader(bitmap, TileMode.CLAMP,
                TileMode.CLAMP);
    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setShader(bitmapShader);
    }

c 在setBounds（）初始化一个 ReactF

@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);
    }

d 在draw（）方法里面调用

canvas.draw（）传入我们的矩形对象和画笔

canvas.drawRoundRect(rectF, 30, 30, mPaint);

效果图如下

![Center][]

源码如下：

package com.xujun.administrator.customdrawable.view;
    
    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.TileMode;
    import android.graphics.drawable.Drawable;
    
    public class RoundImageDrawable extends Drawable {
    
        private Paint mPaint;
        private Bitmap mBitmap;
    
        private RectF rectF;
    
        public RoundImageDrawable(Bitmap bitmap) {
            mBitmap = bitmap;
            BitmapShader bitmapShader = new BitmapShader(bitmap, TileMode.CLAMP,
                    TileMode.CLAMP);
            mPaint = new Paint();
            mPaint.setAntiAlias(true);
            mPaint.setShader(bitmapShader);
        }
    
        @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 draw(Canvas canvas) {
    //圆角的 半斤可以通过参数传递进来，这里写死了
            canvas.drawRoundRect(rectF, 30, 30, mPaint);
    
        }
    
        @Override
        public int getIntrinsicWidth() {
            return mBitmap.getWidth();
        }
    
        @Override
        public int getIntrinsicHeight() {
            return mBitmap.getHeight();
        }
    
        @Override
        public void setAlpha(int alpha) {
            mPaint.setAlpha(alpha);
        }
    
        @Override
        public void setColorFilter(ColorFilter cf) {
            mPaint.setColorFilter(cf);
        }
    
        @Override
        public int getOpacity() {
            return PixelFormat.TRANSLUCENT;
        }
    
    }

**   ** **2  自定义圆形图片**

a 继承drawable，重写里面的几个方法

b 通过构造方法传入Bitmap对象，初始化一个BitmapShader，将其传递给我们的画笔

public CircleImageDrawable(Bitmap bitmap) {
            mBitmap = bitmap;
            BitmapShader bitmapShader = new BitmapShader(bitmap, TileMode.CLAMP,
                    TileMode.CLAMP);
            mPaint = new Paint();
            mPaint.setAntiAlias(true);
            mPaint.setShader(bitmapShader);
    //        选择我们的半径为较小的那个
            mWidth = Math.min(mBitmap.getWidth(), mBitmap.getHeight());
        }

c 在Draw（）方法里面调用

canvas.draw（）传入我们的矩形对象和画笔

canvas.drawCircle(mWidth / 2, mWidth / 2, mWidth / 2, mPaint);

**效果图如下**

**![Center][]**

**[例子源码下载地址：][Link 2]**

[https://github.com/gdutxiaoxu/CustomDrawable][Link 2]

[Link 1]: http://write.blog.csdn.net/postedit/51226071
[Link 2]: https://github.com/gdutxiaoxu/CustomDrawable
[Center]: /images/20220724/9a0cb2bcc58f4f09b7e3cbda159510ae.png