Unit testing ButtonDropTarget
Originally there was a bug in a method (isTextClippedVertically) in ButtonDropTarget. While attempting to write a unit test it became necessary to refactor ButtonDropTarget and DeleteDropTarget to decouple them from their dependency on launcher in order to allow for a unit test to be written
The pattern we are introducing here is to decouple Launcher from a controller, in order to facilitate easier testing.
Instead of calling Launcher.getLauncher() we call the method through ActivityContext, which has a testing wrapper already defined. Here is a diagram that explains the old and new pattern
Design Pattern: https://screenshot.googleplex.com/7apiE2DaGDrFzy9.png
Test: isTextClippedVerticallyTest
Bug: b/274402490
Change-Id: I1f3003d0b62dddbceb6e492b15aa5d7352d3a293
diff --git a/src/com/android/launcher3/DropTargetHandler.kt b/src/com/android/launcher3/DropTargetHandler.kt
new file mode 100644
index 0000000..277f8b3
--- /dev/null
+++ b/src/com/android/launcher3/DropTargetHandler.kt
@@ -0,0 +1,119 @@
+package com.android.launcher3
+
+import android.content.ComponentName
+import android.view.View
+import com.android.launcher3.DropTarget.DragObject
+import com.android.launcher3.SecondaryDropTarget.DeferredOnComplete
+import com.android.launcher3.dragndrop.DragLayer
+import com.android.launcher3.logging.StatsLogManager.LauncherEvent
+import com.android.launcher3.model.ModelWriter
+import com.android.launcher3.model.data.ItemInfo
+import com.android.launcher3.model.data.LauncherAppWidgetInfo
+import com.android.launcher3.util.IntSet
+import com.android.launcher3.util.PendingRequestArgs
+import com.android.launcher3.views.Snackbar
+
+/**
+ * Handler class for drop target actions that require modifying or interacting with launcher.
+ *
+ * This class is created by Launcher and provided the instance of launcher when created, which
+ * allows us to decouple drop target controllers from Launcher to enable easier testing.
+ */
+class DropTargetHandler(launcher: Launcher) {
+ val mLauncher: Launcher = launcher
+
+ val modelWriter: ModelWriter = mLauncher.modelWriter
+
+ fun onDropAnimationComplete() {
+ mLauncher.stateManager.goToState(LauncherState.NORMAL)
+ }
+
+ fun onSecondaryTargetCompleteDrop(target: ComponentName?, d: DragObject) {
+ when (val dragSource = d.dragSource) {
+ is DeferredOnComplete -> {
+ val deferred: DeferredOnComplete = dragSource
+ if (d.dragSource is SecondaryDropTarget.DeferredOnComplete) {
+ target?.let {
+ deferred.mPackageName = it.packageName
+ mLauncher.addOnResumeCallback { deferred.onLauncherResume() }
+ }
+ ?: deferred.sendFailure()
+ }
+ }
+ }
+ }
+
+ fun reconfigureWidget(widgetId: Int, info: ItemInfo) {
+ mLauncher.setWaitingForResult(PendingRequestArgs.forWidgetInfo(widgetId, null, info))
+ mLauncher.appWidgetHolder.startConfigActivity(
+ mLauncher,
+ widgetId,
+ Launcher.REQUEST_RECONFIGURE_APPWIDGET
+ )
+ }
+
+ fun dismissPrediction(
+ announcement: CharSequence,
+ onActionClicked: Runnable,
+ onDismiss: Runnable?
+ ) {
+ mLauncher.dragLayer.announceForAccessibility(announcement)
+ Snackbar.show(mLauncher, R.string.item_removed, R.string.undo, onDismiss, onActionClicked)
+ }
+
+ fun getViewUnderDrag(info: ItemInfo): View? {
+ return if (
+ info is LauncherAppWidgetInfo &&
+ info.container == LauncherSettings.Favorites.CONTAINER_DESKTOP &&
+ mLauncher.workspace.dragInfo != null
+ ) {
+ mLauncher.workspace.dragInfo.cell
+ } else null
+ }
+
+ fun prepareToUndoDelete() {
+ mLauncher.modelWriter.prepareToUndoDelete()
+ }
+
+ fun onDeleteComplete(item: ItemInfo) {
+ var pageItem: ItemInfo = item
+ if (item.container <= 0) {
+ val v = mLauncher.workspace.getHomescreenIconByItemId(item.container)
+ v?.let { pageItem = v.tag as ItemInfo }
+ }
+ val pageIds =
+ if (pageItem.container == LauncherSettings.Favorites.CONTAINER_DESKTOP)
+ IntSet.wrap(pageItem.screenId)
+ else mLauncher.workspace.currentPageScreenIds
+ val onUndoClicked = Runnable {
+ mLauncher.setPagesToBindSynchronously(pageIds)
+ modelWriter.abortDelete()
+ mLauncher.statsLogManager.logger().log(LauncherEvent.LAUNCHER_UNDO)
+ }
+
+ Snackbar.show(
+ mLauncher,
+ R.string.item_removed,
+ R.string.undo,
+ modelWriter::commitDelete,
+ onUndoClicked
+ )
+ }
+
+ fun onAccessibilityDelete(view: View?, item: ItemInfo, announcement: CharSequence) {
+ // Remove the item from launcher and the db, we can ignore the containerInfo in this call
+ // because we already remove the drag view from the folder (if the drag originated from
+ // a folder) in Folder.beginDrag()
+ mLauncher.removeItem(view, item, true /* deleteFromDb */, "removed by accessibility drop")
+ mLauncher.workspace.stripEmptyScreens()
+ mLauncher.dragLayer.announceForAccessibility(announcement)
+ }
+
+ fun getDragLayer(): DragLayer {
+ return mLauncher.dragLayer
+ }
+
+ fun onClick(buttonDropTarget: ButtonDropTarget) {
+ mLauncher.accessibilityDelegate.handleAccessibleDrop(buttonDropTarget, null, null)
+ }
+}
