Android Glide RadiusTransform

import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.support.annotation.NonNull;

import com.bumptech.glide.load.engine.bitmap_recycle.BitmapPool;
import com.bumptech.glide.load.resource.bitmap.BitmapTransformation;

import java.nio.ByteBuffer;
import java.security.MessageDigest;

/**
 * @author Relin
 * @date 2019-10-18 10:18:20
 * 圆角转化工具类

 * 支持4个角自定义，同时支持4个角同时定义。

 */
public class RadiusTransform extends BitmapTransformation {

    private static final String ID = RadiusTransform.class.getPackage().getName() + RadiusTransform.class.getName();
    
    private static final byte[] ID_BYTES = ID.getBytes(CHARSET);

    /**
     * 左上圆角
     */
    private int topLeftRadius;

    /**
     * 右上圆角
     */
    private int topRightRadius;
    /**
     * 下左圆角
     */
    private int bottomLeftRadius;

    /**
     * 下右圆角
     */
    private int bottomRightRadius;

    /**
     * 设置4角圆角大小
     *
     * @param radius 圆角大小
     */
    public RadiusTransform(int radius) {
        this.topLeftRadius = radius;
        this.topRightRadius = radius;
        this.bottomLeftRadius = radius;
        this.bottomRightRadius = radius;
    }

    /**
     * 分别设置4个角的圆角大小
     *
     * @param topLeftRadius     左上圆角
     * @param topRightRadius    右上圆角
     * @param bottomLeftRadius  下左圆角
     * @param bottomRightRadius 下右圆角
     */
    public RadiusTransform(int topLeftRadius, int topRightRadius, int bottomLeftRadius, int bottomRightRadius) {
        this.topLeftRadius = topLeftRadius;
        this.topRightRadius = topRightRadius;
        this.bottomLeftRadius = bottomLeftRadius;
        this.bottomRightRadius = bottomRightRadius;
    }

    @Override
    protected Bitmap transform(@NonNull BitmapPool pool, @NonNull Bitmap toTransform, int outWidth, int outHeight) {
        int width = toTransform.getWidth();
        int height = toTransform.getHeight();
        Bitmap bitmap = pool.get(width, height, Bitmap.Config.ARGB_8888);
        bitmap.setHasAlpha(true);
        bitmap.setDensity(toTransform.getDensity());
        Canvas canvas = new Canvas(bitmap);
        Paint paint = new Paint();
        paint.setAntiAlias(true);
        paint.setShader(new BitmapShader(toTransform, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP));
        //左上
        canvas.drawRoundRect(new RectF(0, 0, width / 2, height / 2), topLeftRadius, topLeftRadius, paint);
        //右上
        canvas.drawRoundRect(new RectF(width / 2, 0, width, height / 2), topRightRadius, topRightRadius, paint);
        //下左
        canvas.drawRoundRect(new RectF(0, height / 2, height / 2, height), bottomLeftRadius, bottomLeftRadius, paint);
        //下右边
        canvas.drawRoundRect(new RectF(width / 2, height / 2, width, height), bottomRightRadius, bottomRightRadius, paint);
        //填充空白
        canvas.drawRect(new Rect(width / 4, 0, width * 3 / 4, height), paint);
        canvas.drawRect(new Rect(0, height / 4, width, height * 3 / 4), paint);
        return bitmap;
    }

    @Override
    public void updateDiskCacheKey(MessageDigest messageDigest) {
        messageDigest.update(ID_BYTES);
    }

}