From 0dd8345085d059a570859e8cb5376299ed650c2a Mon Sep 17 00:00:00 2001
From: Tony Wickham <twickham@google.com>
Date: Fri, 4 Jun 2021 20:53:48 -0700
Subject: [PATCH] Fix regression where nav bar shows when taskbar is showing

- Add mNavBarButtonAlpha to TaskbarStateHandler, and set it to the inverse of the taskbar alpha.
- Add mPendingSetNavButtonAlpha for when setNavBarButtonAlpha() is called before mSystemUiProxy is initialized.

Test: Go between various launcher states and ensure nav bar only shows up when taskbar hides.
Bug: 187353581
Change-Id: I4b79280d686c787e9128e753070ec591d1ab2e4d
---
 .../taskbar/TaskbarStateHandler.java          | 16 ++++++++++++
 .../com/android/quickstep/SystemUiProxy.java  | 26 +++++++++++++------
 2 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/quickstep/src/com/android/launcher3/taskbar/TaskbarStateHandler.java b/quickstep/src/com/android/launcher3/taskbar/TaskbarStateHandler.java
index e56ee8710b..20d4133a97 100644
--- a/quickstep/src/com/android/launcher3/taskbar/TaskbarStateHandler.java
+++ b/quickstep/src/com/android/launcher3/taskbar/TaskbarStateHandler.java
@@ -27,6 +27,8 @@ import com.android.launcher3.anim.PropertySetter;
 import com.android.launcher3.statemanager.StateManager;
 import com.android.launcher3.states.StateAnimationConfig;
 import com.android.launcher3.util.MultiValueAlpha;
+import com.android.quickstep.AnimatedFloat;
+import com.android.quickstep.SystemUiProxy;
 
 /**
  * StateHandler to animate Taskbar according to Launcher's state machine. Does nothing if Taskbar
@@ -39,12 +41,17 @@ public class TaskbarStateHandler implements StateManager.StateHandler<LauncherSt
     // Contains Taskbar-related properties we should aniamte. If null, don't do anything.
     private @Nullable MultiValueAlpha.AlphaProperty mTaskbarAlpha = null;
 
+    private AnimatedFloat mNavbarButtonAlpha = new AnimatedFloat(this::updateNavbarButtonAlpha);
+
     public TaskbarStateHandler(BaseQuickstepLauncher launcher) {
         mLauncher = launcher;
     }
 
     public void setAnimationController(MultiValueAlpha.AlphaProperty taskbarAlpha) {
         mTaskbarAlpha = taskbarAlpha;
+        // Reapply state.
+        setState(mLauncher.getStateManager().getState());
+        updateNavbarButtonAlpha();
     }
 
     @Override
@@ -68,5 +75,14 @@ public class TaskbarStateHandler implements StateManager.StateHandler<LauncherSt
 
         boolean isTaskbarVisible = (toState.getVisibleElements(mLauncher) & TASKBAR) != 0;
         setter.setFloat(mTaskbarAlpha, MultiValueAlpha.VALUE, isTaskbarVisible ? 1f : 0f, LINEAR);
+        // Make the nav bar visible in states that taskbar isn't visible.
+        // TODO: We should draw our own handle instead of showing the nav bar.
+        float navbarButtonAlpha = isTaskbarVisible ? 0f : 1f;
+        setter.setFloat(mNavbarButtonAlpha, AnimatedFloat.VALUE, navbarButtonAlpha, LINEAR);
+    }
+
+
+    private void updateNavbarButtonAlpha() {
+        SystemUiProxy.INSTANCE.get(mLauncher).setNavBarButtonAlpha(mNavbarButtonAlpha.value, false);
     }
 }
diff --git a/quickstep/src/com/android/quickstep/SystemUiProxy.java b/quickstep/src/com/android/quickstep/SystemUiProxy.java
index d040904f98..090fd015a4 100644
--- a/quickstep/src/com/android/quickstep/SystemUiProxy.java
+++ b/quickstep/src/com/android/quickstep/SystemUiProxy.java
@@ -85,6 +85,7 @@ public class SystemUiProxy implements ISystemUiProxy,
     private float mLastNavButtonAlpha;
     private boolean mLastNavButtonAnimate;
     private boolean mHasNavButtonAlphaBeenSet = false;
+    private Runnable mPendingSetNavButtonAlpha = null;
 
     // TODO(141886704): Find a way to remove this
     private int mLastSystemUiStateFlags;
@@ -157,6 +158,11 @@ public class SystemUiProxy implements ISystemUiProxy,
             setSmartspaceCallback(mPendingSmartspaceCallback);
             mPendingSmartspaceCallback = null;
         }
+
+        if (mPendingSetNavButtonAlpha != null) {
+            mPendingSetNavButtonAlpha.run();
+            mPendingSetNavButtonAlpha = null;
+        }
     }
 
     public void clearProxy() {
@@ -240,14 +246,18 @@ public class SystemUiProxy implements ISystemUiProxy,
         boolean changed = Float.compare(alpha, mLastNavButtonAlpha) != 0
                 || animate != mLastNavButtonAnimate
                 || !mHasNavButtonAlphaBeenSet;
-        if (mSystemUiProxy != null && changed) {
-            mLastNavButtonAlpha = alpha;
-            mLastNavButtonAnimate = animate;
-            mHasNavButtonAlphaBeenSet = true;
-            try {
-                mSystemUiProxy.setNavBarButtonAlpha(alpha, animate);
-            } catch (RemoteException e) {
-                Log.w(TAG, "Failed call setNavBarButtonAlpha", e);
+        if (changed) {
+            if (mSystemUiProxy == null) {
+                mPendingSetNavButtonAlpha = () -> setNavBarButtonAlpha(alpha, animate);
+            } else {
+                mLastNavButtonAlpha = alpha;
+                mLastNavButtonAnimate = animate;
+                mHasNavButtonAlphaBeenSet = true;
+                try {
+                    mSystemUiProxy.setNavBarButtonAlpha(alpha, animate);
+                } catch (RemoteException e) {
+                    Log.w(TAG, "Failed call setNavBarButtonAlpha", e);
+                }
             }
         }
     }