Revert "Revert "Enable FLAG_SLIPPERY window flag when swipe down on workspace""

This reverts commit c4c8b3c695.

Reason for revert: Re-enabling for R1

Change-Id: Id6706c548dcc9debbfaf2069164636bc22aa9b5e

quickstep/src/com/android/launcher3/uioverrides/touchcontrollers/StatusBarTouchController.java

@@ -17,17 +17,22 @@ package com.android.launcher3.uioverrides.touchcontrollers;
 
 import static android.view.MotionEvent.ACTION_DOWN;
 import static android.view.MotionEvent.ACTION_MOVE;
+import static android.view.MotionEvent.ACTION_UP;
+import static android.view.MotionEvent.ACTION_CANCEL;
 
+import android.graphics.PointF;
 import android.os.RemoteException;
 import android.util.Log;
+import android.util.SparseArray;
 import android.view.MotionEvent;
 import android.view.ViewConfiguration;
+import android.view.Window;
+import android.view.WindowManager;
 
 import com.android.launcher3.AbstractFloatingView;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherState;
-import com.android.launcher3.touch.TouchEventTranslator;
 import com.android.launcher3.util.TouchController;
 import com.android.quickstep.RecentsModel;
 import com.android.systemui.shared.recents.ISystemUiProxy;
@@ -36,18 +41,29 @@ import java.io.PrintWriter;
 
 /**
  * TouchController for handling touch events that get sent to the StatusBar. Once the
- * Once the event delta y passes the touch slop, the events start getting forwarded.
+ * Once the event delta mDownY passes the touch slop, the events start getting forwarded.
  * All events are offset by initial Y value of the pointer.
  */
 public class StatusBarTouchController implements TouchController {
 
     private static final String TAG = "StatusBarController";
 
+    /**
+     * Window flag: Enable touches to slide out of a window into neighboring
+     * windows in mid-gesture instead of being captured for the duration of
+     * the gesture.
+     *
+     * This flag changes the behavior of touch focus for this window only.
+     * Touches can slide out of the window but they cannot necessarily slide
+     * back in (unless the other window with touch focus permits it).
+     */
+    private static final int FLAG_SLIPPERY = 0x20000000;
+
     protected final Launcher mLauncher;
-    protected final TouchEventTranslator mTranslator;
     private final float mTouchSlop;
     private ISystemUiProxy mSysUiProxy;
     private int mLastAction;
+    private final SparseArray<PointF> mDownEvents;
 
     /* If {@code false}, this controller should not handle the input {@link MotionEvent}.*/
     private boolean mCanIntercept;
@@ -56,7 +72,7 @@ public class StatusBarTouchController implements TouchController {
         mLauncher = l;
         // Guard against TAPs by increasing the touch slop.
         mTouchSlop = 2 * ViewConfiguration.get(l).getScaledTouchSlop();
-        mTranslator = new TouchEventTranslator((MotionEvent ev)-> dispatchTouchEvent(ev));
+        mDownEvents = new SparseArray<>();
     }
 
     @Override
@@ -64,7 +80,6 @@ public class StatusBarTouchController implements TouchController {
         writer.println(prefix + "mCanIntercept:" + mCanIntercept);
         writer.println(prefix + "mLastAction:" + MotionEvent.actionToString(mLastAction));
         writer.println(prefix + "mSysUiProxy available:" + (mSysUiProxy != null));
-
     }
 
     private void dispatchTouchEvent(MotionEvent ev) {
@@ -81,26 +96,31 @@ public class StatusBarTouchController implements TouchController {
     @Override
     public final boolean onControllerInterceptTouchEvent(MotionEvent ev) {
         int action = ev.getActionMasked();
+        int idx = ev.getActionIndex();
+        int pid = ev.getPointerId(idx);
         if (action == ACTION_DOWN) {
             mCanIntercept = canInterceptTouch(ev);
             if (!mCanIntercept) {
                 return false;
             }
-            mTranslator.reset();
-            mTranslator.setDownParameters(0, ev);
+            mDownEvents.put(pid, new PointF(ev.getX(), ev.getY()));
         } else if (ev.getActionMasked() == MotionEvent.ACTION_POINTER_DOWN) {
-            // Check!! should only set it only when threshold is not entered.
-            mTranslator.setDownParameters(ev.getActionIndex(), ev);
+           // Check!! should only set it only when threshold is not entered.
+           mDownEvents.put(pid, new PointF(ev.getX(idx), ev.getY(idx)));
         }
         if (!mCanIntercept) {
             return false;
         }
         if (action == ACTION_MOVE) {
-            float dy = ev.getY() - mTranslator.getDownY();
-            float dx = ev.getX() - mTranslator.getDownX();
-            if (dy > mTouchSlop && dy > Math.abs(dx)) {
-                mTranslator.dispatchDownEvents(ev);
-                mTranslator.processMotionEvent(ev);
+            float dy = ev.getY(idx) - mDownEvents.get(pid).y;
+            float dx = ev.getX(idx) - mDownEvents.get(pid).x;
+            // Currently input dispatcher will not do touch transfer if there are more than
+            // one touch pointer. Hence, even if slope passed, only set the slippery flag
+            // when there is single touch event. (context: InputDispatcher.cpp line 1445)
+            if (dy > mTouchSlop && dy > Math.abs(dx) && ev.getPointerCount() == 1) {
+                ev.setAction(ACTION_DOWN);
+                dispatchTouchEvent(ev);
+                setWindowSlippery(true);
                 return true;
             }
             if (Math.abs(dx) > mTouchSlop) {
@@ -110,13 +130,27 @@ public class StatusBarTouchController implements TouchController {
         return false;
     }
 
-
     @Override
     public final boolean onControllerTouchEvent(MotionEvent ev) {
-        mTranslator.processMotionEvent(ev);
+        if (ev.getAction() == ACTION_UP || ev.getAction() == ACTION_CANCEL) {
+            dispatchTouchEvent(ev);
+            setWindowSlippery(false);
+            return true;
+        }
         return true;
     }
 
+    private void setWindowSlippery(boolean enable) {
+        Window w = mLauncher.getWindow();
+        WindowManager.LayoutParams wlp = w.getAttributes();
+        if (enable) {
+            wlp.flags |= FLAG_SLIPPERY;
+        } else {
+            wlp.flags &= ~FLAG_SLIPPERY;
+        }
+        w.setAttributes(wlp);
+    }
+
     private boolean canInterceptTouch(MotionEvent ev) {
         if (!mLauncher.isInState(LauncherState.NORMAL) ||
                 AbstractFloatingView.getTopOpenViewWithType(mLauncher,
@@ -132,4 +166,4 @@ public class StatusBarTouchController implements TouchController {
         mSysUiProxy = RecentsModel.INSTANCE.get(mLauncher).getSystemUiProxy();
         return mSysUiProxy != null;
     }
-}
+}