Add loading image only from cache

DetailActivity.kt

override fun onCreate(savedInstanceState: Bundle?) {
    ...
    detailImage.load(url, loadOnlyFromCache = true) {
        supportStartPostponedEnterTransition()
    }
}

GlideLoader.kt

fun ImageView.load(url: String, loadOnlyFromCache: Boolean = false, onLoadingFinished: () -> Unit = {}) {
    ...
    val requestOptions = RequestOptions.placeholderOf(R.drawable.placeholder)
            .dontTransform()
            .onlyRetrieveFromCache(loadOnlyFromCache)
    ...
}