ViewHelper { public static void setBackground(EfficientCacheView cacheView, int viewId, Drawable drawable) { View view = cacheView.findViewByIdEfficient(viewId); if (view != null) { if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) { view.setBackgroundDrawable(drawable); } else { view.setBackground(drawable); } } }  static void setVisibility(EfficientCacheView cacheView, int viewId, int visibility); static void setBackground(EfficientCacheView cacheView, int viewId, Drawable drawable); static void setBackgroundColor(EfficientCacheView cacheView, int viewId,
            @ColorInt int color); static void setBackgroundResource(EfficientCacheView cacheView, int viewId,
            @DrawableRes int resid); static void setTag(EfficientCacheView cacheView, int viewId, Object tag); static void setTag(EfficientCacheView cacheView, int viewId, int key, Object tag); static void setText(EfficientCacheView cacheView, int viewId, CharSequence text); static void setText(EfficientCacheView cacheView, int viewId, @StringRes int resid); static void setTextColor(EfficientCacheView cacheView, int viewId, @ColorInt int color); static void setTextSize(EfficientCacheView cacheView, int viewId, float size); static void setTextSize(EfficientCacheView cacheView, int viewId, int unit, float size); static void setImageResource(EfficientCacheView cacheView, int viewId,
            @DrawableRes int resId); static void setImageDrawable(EfficientCacheView cacheView, int viewId,
            Drawable drawable); static void setImageUri(EfficientCacheView cacheView, int viewId, @Nullable Uri uri); static void setImageBitmap(EfficientCacheView cacheView, int viewId, Bitmap bm);  }
@Test public void testSetBackground() throws Exception { Drawable drawable = Mockito.mock(Drawable.class); ViewHelper.setBackground(mCacheView, NULL_VIEW_ID, drawable); ViewHelper.setBackground(mCacheView, VIEW_ID, drawable); ViewHelper.setBackground(mCacheView, IMAGEVIEW_ID, drawable); ViewHelper.setBackground(mCacheView, TEXTVIEW_ID, drawable); verify(mView).setBackgroundDrawable(drawable); verify(mImageView).setBackgroundDrawable(drawable); verify(mTextView).setBackgroundDrawable(drawable); verifyNoMoreInteractions(mView, mImageView, mTextView); }