glide 设置圆角导致图片变形？

glide 设置圆角的时候会导致ImageView的scaleType属性无效？导致图片变形？

原因：属性覆盖了。

为什么呢，其实是因为重复调用了transform方法导致的，

比如new CenterCrop(mContext)或者是new RequestOptions().centerCrop()

public class CenterCrop extends BitmapTransformation {
  ....

  // Bitmap doesn't implement equals, so == and .equals are equivalent here.
  @SuppressWarnings("PMD.CompareObjectsWithEquals")
  @Override
  protected Bitmap transform(
      @NonNull BitmapPool pool, @NonNull Bitmap toTransform, int outWidth, int outHeight) {
    return TransformationUtils.centerCrop(pool, toTransform, outWidth, outHeight);
  }
}

  public RequestOptions centerCrop() {
    return transform(DownsampleStrategy.CENTER_OUTSIDE, new CenterCrop());
  }

可以看到都有调用transform方法的，

再看一种写法

new  RequestOptions().centerCrop().transform(...);

很明显重复了，centerCrop内部已经调用了transform方法，然后后面又跟了一个transform。

解决思路：既然多次调用会覆盖，那就一次调用多个属性。

自定义一个类去继承BitmapTransformation：

/**
 * Created by yechaoa on 2018/9/10.
 * Describe : glide 圆角
 */
public class GlideRoundTransform extends BitmapTransformation {

    private static float radius = 0f;

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

    @Override
    protected Bitmap transform(@NonNull BitmapPool pool, @NonNull Bitmap toTransform, int outWidth, int outHeight) {
        Bitmap bitmap = TransformationUtils.centerCrop(pool, toTransform, outWidth, outHeight);
        return roundCrop(pool, bitmap);
    }

    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);

        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;
    }

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

    @Override
    public void updateDiskCacheKey(MessageDigest messageDigest) {

    }

}

调用：

参数直接传圆角的度数就行

        RequestOptions options =new  RequestOptions().transform(new GlideRoundTransform(5));
        Glide.with(mContext).load(...).apply(options).into(...);