Finer dispatch for ViewModels init

vlc-android/src/org/videolan/vlc/viewmodels/BaseModel.kt

@@ -54,7 +54,7 @@ abstract class BaseModel<T : MediaLibraryItem> : ViewModel(), RefreshModel {
     private val filter by lazy(LazyThreadSafetyMode.NONE) { FilterDelegate(dataset) }
 
     val dataset by lazy {
-        launch(UI) { fetch() }
+        fetch()
         LiveDataset<T>()
     }
 

vlc-android/src/org/videolan/vlc/viewmodels/MedialibraryModel.kt

@@ -27,6 +27,7 @@ import org.videolan.medialibrary.interfaces.MediaAddedCb
 import org.videolan.medialibrary.interfaces.MediaUpdatedCb
 import org.videolan.medialibrary.media.MediaLibraryItem
 import org.videolan.vlc.util.EmptyMLCallbacks
+import org.videolan.vlc.util.uiStart
 
 
 abstract class MedialibraryModel<T : MediaLibraryItem> : BaseModel<T>(), Medialibrary.OnMedialibraryReadyListener, MediaUpdatedCb by EmptyMLCallbacks, MediaAddedCb by EmptyMLCallbacks {
@@ -39,11 +40,11 @@ abstract class MedialibraryModel<T : MediaLibraryItem> : BaseModel<T>(), Mediali
     }
 
     override fun onMedialibraryReady() {
-        launch(UI) { refresh() }
+        launch(UI, uiStart()) { refresh() }
     }
 
     override fun onMedialibraryIdle() {
-        launch(UI) { refresh() }
+        launch(UI, uiStart()) { refresh() }
     }
 
     override fun onCleared() {

vlc-android/src/org/videolan/vlc/viewmodels/browser/BrowserProvider.kt

@@ -54,12 +54,16 @@ abstract class BrowserProvider(val url: String?, private val showHiddenFiles: Bo
     override fun fetch() {
         val prefetchList by lazy(LazyThreadSafetyMode.NONE) { prefetchLists[url] }
         if (url === null) {
-            browseRoot()
-            parseSubDirectories()
+            launch(UI) {
+                browseRoot()
+                parseSubDirectories()
+            }
         } else if (prefetchList !== null && !prefetchList.isEmpty()) {
-            dataset.value = prefetchList
-            prefetchLists.remove(url)
-            parseSubDirectories()
+            launch(UI) {
+                dataset.value = prefetchList
+                prefetchLists.remove(url)
+                parseSubDirectories()
+            }
         } else browse(url, browserListener)
     }