When dragging past first or last state, don't reinit target

Example bug:
1. Swipe up to overview and let go
2. Swipe all the way to the top of the screen, past where all apps stops
3. Swipe down

Before this change, you get reset in NORMAL state instead of OVERVIEW.

By ensuring that getTargetState() checks the drag direction before
returning a new state, we guarantee we only re-init in the case that the
state is actually changing. Otherwise it's possible to change the state
to one that is impossible, such as NORMAL when swiping up from ALL APPS.

Change-Id: I19913dded9c94228d06289780b6400e99403f378

4 files changed, 14 insertions, 4 deletions

diff --git a/quickstep/src/com/android/launcher3/uioverrides/LandscapeStatesTouchController.java b/quickstep/src/com/android/launcher3/uioverrides/LandscapeStatesTouchController.java
index 355b88d91..30ceb43f9 100644
--- a/quickstep/src/com/android/launcher3/uioverrides/LandscapeStatesTouchController.java
+++ b/quickstep/src/com/android/launcher3/uioverrides/LandscapeStatesTouchController.java
@@ -60,12 +60,13 @@ public class LandscapeStatesTouchController extends PortraitStatesTouchControlle
 
     @Override
     protected LauncherState getTargetState(LauncherState fromState, boolean isDragTowardPositive) {
-        if (fromState == ALL_APPS) {
+        if (fromState == ALL_APPS && !isDragTowardPositive) {
             // Should swipe down go to OVERVIEW instead?
             return TouchInteractionService.isConnected() ?
                     mLauncher.getStateManager().getLastState() : NORMAL;
-        } else {
+        } else if (isDragTowardPositive) {
             return ALL_APPS;
         }
+        return fromState;
     }
 }
diff --git a/quickstep/src/com/android/launcher3/uioverrides/PortraitStatesTouchController.java b/quickstep/src/com/android/launcher3/uioverrides/PortraitStatesTouchController.java
index 1b65ca0b0..c92264f3a 100644
--- a/quickstep/src/com/android/launcher3/uioverrides/PortraitStatesTouchController.java
+++ b/quickstep/src/com/android/launcher3/uioverrides/PortraitStatesTouchController.java
@@ -140,7 +140,7 @@ public class PortraitStatesTouchController extends AbstractStateChangeTouchContr
 
     @Override
     protected LauncherState getTargetState(LauncherState fromState, boolean isDragTowardPositive) {
-        if (fromState == ALL_APPS) {
+        if (fromState == ALL_APPS && !isDragTowardPositive) {
             // Should swipe down go to OVERVIEW instead?
             return TouchInteractionService.isConnected() ?
                     mLauncher.getStateManager().getLastState() : NORMAL;
diff --git a/src/com/android/launcher3/touch/AbstractStateChangeTouchController.java b/src/com/android/launcher3/touch/AbstractStateChangeTouchController.java
index 9726704dd..3d85ac3c6 100644
--- a/src/com/android/launcher3/touch/AbstractStateChangeTouchController.java
+++ b/src/com/android/launcher3/touch/AbstractStateChangeTouchController.java
@@ -124,6 +124,10 @@ public abstract class AbstractStateChangeTouchController extends AnimatorListene
         return mLauncher.getAllAppsController().getShiftRange();
     }
 
+    /**
+     * Returns the state to go to from fromState given the drag direction. If there is no state in
+     * that direction, returns fromState.
+     */
     protected abstract LauncherState getTargetState(LauncherState fromState,
             boolean isDragTowardPositive);
 
diff --git a/src_ui_overrides/com/android/launcher3/uioverrides/AllAppsSwipeController.java b/src_ui_overrides/com/android/launcher3/uioverrides/AllAppsSwipeController.java
index c97c3ccec..d1cddc18f 100644
--- a/src_ui_overrides/com/android/launcher3/uioverrides/AllAppsSwipeController.java
+++ b/src_ui_overrides/com/android/launcher3/uioverrides/AllAppsSwipeController.java
@@ -54,7 +54,12 @@ public class AllAppsSwipeController extends AbstractStateChangeTouchController {
 
     @Override
     protected LauncherState getTargetState(LauncherState fromState, boolean isDragTowardPositive) {
-        return fromState == ALL_APPS ? NORMAL : ALL_APPS;
+        if (fromState == NORMAL && isDragTowardPositive) {
+            return ALL_APPS;
+        } else if (fromState == ALL_APPS && !isDragTowardPositive) {
+            return NORMAL;
+        }
+        return fromState;
     }
 
     @Override