Glide的加载图片的帮助类,用来把图片圆角或者改成圆形图片

Glide虽然非常好用但是没找到把图片圆角的方法,所以百度了一个非常不错的加载类自己实现圆角图

感谢原文章作者:http://blog.csdn.net/weidongjian/article/details/47144549

自定义一个extend BitmapTransformation的方法，把获得的bitmap转化成圆形图片

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RectF;

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

/**
 * 这是一个Glide的加载图片的帮助类,用来把图片圆角
 * Created by Lizhanqi on 2016/9/16 0016.
 */
public class GlideRoundTransform extends BitmapTransformation {

    private static float radius = 0f;

    public GlideRoundTransform(Context context) {
        this(context, 4);
    }

    public GlideRoundTransform(Context context, int dp) {
        super(context);
        this.radius = Resources.getSystem().getDisplayMetrics().density * dp;
    }

    @Override protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) {
        return roundCrop(pool, toTransform);
    }

    private static Bitmap roundCrop(BitmapPool pool, Bitmap source) {
        if (source == null) return null;

        Bitmap result = pool.get(source.getWidth(), source.getHeight(), Bitmap.Config.ARGB_8888);
        if (result == null) {
            result = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Bitmap.Config.ARGB_8888);
        }

        Canvas canvas = new Canvas(result);
        Paint paint = new Paint();
        paint.setShader(new BitmapShader(source, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP));
        paint.setAntiAlias(true);
        RectF rectF = new RectF(0f, 0f, source.getWidth(), source.getHeight());
        canvas.drawRoundRect(rectF, radius, radius, paint);
        return result;
    }

    @Override public String getId() {
        return getClass().getName() + Math.round(radius);
    }
}

使用方式:

private RequestManager glideRequest= Glide.with(this);

//加载圆形图

glideRequest.load("https://www.baidu.com/img/bdlogo.png")

//最重要就是调用这个方法实现,只传入一个上下文那么他会把图片画成圆形图,传入数字,自定义圆角的角度

.transform(new GlideCircleTransform(context))

.into(imageView);

　//自定义圆角的角度实现圆角矩形

　 glideRequest.load("https://www.baidu.com/img/bdlogo.png").transform(new GlideRoundTransform(context, 10)).into(imageView);