Memory leak at the sample app's RecyclerViewActivity

[Tobibur]

This is a very nice & useful library you made. I was checking the sample app and got this memory leak notification.

[Piasy]

Hi, I'm busy these days, could you please do some investigation about this problem? PR is welcome!

[xujiaji]

我是在自定义Application中创建一个方法通过反射清理掉引用，在对应的Activity的onDestroy生命周期调用一下cleanGlideLoading()

    public void cleanGlideLoading() {
        Field mRequestTargetMap = null;
        try {
            mRequestTargetMap = mGlideImageLoader.getClass().getDeclaredField("mRequestTargetMap");
            mRequestTargetMap.setAccessible(true);
            Map map = (Map) mRequestTargetMap.get(mGlideImageLoader);
            map.clear();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }

[Piasy]

@xujiaji 可以考虑为 ImageLoader 增加一个接口，用于显式清理资源，供使用者调用。欢迎提交 PR。