Glide 绘制边框

圆形Glide 内部已经实现。但描边效果需要我们自己绘制。在项目当中使用 CircleImageView 实现该效果，但是Glide 与 CircleImageView 组合使用重现种种问题，虽说网上有相关解决方案，但是想想还是从根源上解决，为此我们需要 继承BitmapTransformation ，重写 transform 实现前述所说效果。直接看实现：
效果图如下：

这里写图片描述

圆形描边效果实现。

代码：

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Paint;

import com.bumptech.glide.load.engine.bitmap_recycle.BitmapPool;

import java.security.MessageDigest;

import jp.wasabeef.glide.transformations.BitmapTransformation;

/**
 * Glide 的图形变换可参考Glide 示例源码
 * {@link com.bumptech.glide.load.resource.bitmap.CenterCrop}
 * {@link com.bumptech.glide.load.resource.bitmap.BitmapTransformation}
 *
 */

public class GlideCircleBorderTransform extends BitmapTransformation {
    private final String ID = getClass().getName();
    private Paint mBorderPaint;
    private float borderWidth;
    private int borderColor;


    public GlideCircleBorderTransform(float borderWidth, int borderColor) {
        this.borderWidth = borderWidth;
        this.borderColor = borderColor;
        mBorderPaint = new Paint();
        mBorderPaint.setColor(borderColor);
        mBorderPaint.setStyle(Paint.Style.STROKE);
        mBorderPaint.setAntiAlias(true);
        mBorderPaint.setStrokeWidth(borderWidth);
        mBorderPaint.setDither(true);

    }

    @Override
    protected Bitmap transform(Context context, BitmapPool bitmapPool, Bitmap bitmap, int i, int i1) {
        return circleCrop(bitmapPool, bitmap);
    }

    private Bitmap circleCrop(BitmapPool bitmapPool, Bitmap source) {
        
        int size = Math.min(source.getWidth(), source.getHeight());
        int x = (source.getWidth() - size) / 2;
        int y = (source.getHeight() - size) / 2;
        Bitmap square = Bitmap.createBitmap(source, x, y, size, size);
        Bitmap result = bitmapPool.get(size, size, Bitmap.Config.ARGB_8888);
        if (result == null) {
            result = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
        }

        //画图
        Canvas canvas = new Canvas(result);
        Paint paint = new Paint();
        //设置 Shader
        paint.setShader(new BitmapShader(square, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP));
        paint.setAntiAlias(true);
        float radius = size / 2f;
        //绘制一个圆
        canvas.drawCircle(radius, radius, radius, paint);


        /************************描边*********************/
        //注意：避免出现描边被屏幕边缘裁掉
        float borderRadius = radius - (borderWidth / 2);
        //画边框
        canvas.drawCircle(radius, radius, borderRadius, mBorderPaint);
        return result;
    }

    @Override
    public void updateDiskCacheKey(MessageDigest messageDigest) {
        messageDigest.update(ID.getBytes(CHARSET));
    }

    @Override
    public boolean equals(Object o) {
        return o instanceof GlideCircleBorderTransform;
    }

    @Override
    public int hashCode() {
        return ID.hashCode();
    }
}

使用：

    /**
     * 加载图片-- 圆形+描边展示---不展示渐进动画
     * @param glideContextWrapper
     * @param imageView
     * @param url
     * @param borderWidth
     * @param borderColor
     * @param placeholder
     */
    public static void loadCircle(GlideContextWrapper glideContextWrapper, ImageView imageView, String url, float borderWidth, int borderColor,@IdRes int placeholder) {
        RequestOptions options = new RequestOptions()
                .placeholder(placeholder)
                .fallback(placeholder)
                .centerCrop()
                .bitmapTransform(new GlideCircleBorderTransform(borderWidth, borderColor))
                .diskCacheStrategy(DiskCacheStrategy.DATA);
        ImageLoader.getRequestManager(glideContextWrapper)
                .load(url)
                .apply(options)
                .into(imageView);
    }

详情见：https://blog.csdn.net/wlytctw/article/details/81740915