Update dropzones to match the size of the existing split

The dropzones were always split exactly in half on the screen
which looks weird if you adjust the split to a different size
and then drag new apps into split.

This adjusts the dropzones to match the size of the existing
split.

It also fixes a bug where the existing split bounds weren't
being properly calculated in the policy so the drag and drop
highlight wouldn't switch to the correct side until you
passed through the middle instead of where the divider
actually is.

Bug: 209504662
Test: manual - 1) have apps in split
               2) adjust the divider
               3) start dragging a new app into split, pass
                  across the divider
               => the highlight should immediately switch
               => the highlight should match the size of the
                  existing split
               4) test in landscape & portrait
Change-Id: I3c7a288625ad766d0c467d713a451fe8bfc1d669

2 files changed, 62 insertions, 8 deletions

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragAndDropPolicy.java b/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragAndDropPolicy.java
index b65a2e4ffca6..8e6c05d83906 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragAndDropPolicy.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragAndDropPolicy.java
@@ -151,7 +151,13 @@ public class DragAndDropPolicy {
                 final Rect rightHitRegion = new Rect();
                 final Rect rightDrawRegion = bottomOrRightBounds;
 
-                displayRegion.splitVertically(leftHitRegion, rightHitRegion);
+                // If we have existing split regions use those bounds, otherwise split it 50/50
+                if (inSplitScreen) {
+                    leftHitRegion.set(topOrLeftBounds);
+                    rightHitRegion.set(bottomOrRightBounds);
+                } else {
+                    displayRegion.splitVertically(leftHitRegion, rightHitRegion);
+                }
 
                 mTargets.add(new Target(TYPE_SPLIT_LEFT, leftHitRegion, leftDrawRegion));
                 mTargets.add(new Target(TYPE_SPLIT_RIGHT, rightHitRegion, rightDrawRegion));
@@ -162,8 +168,13 @@ public class DragAndDropPolicy {
                 final Rect bottomHitRegion = new Rect();
                 final Rect bottomDrawRegion = bottomOrRightBounds;
 
-                displayRegion.splitHorizontally(
-                        topHitRegion, bottomHitRegion);
+                // If we have existing split regions use those bounds, otherwise split it 50/50
+                if (inSplitScreen) {
+                    topHitRegion.set(topOrLeftBounds);
+                    bottomHitRegion.set(bottomOrRightBounds);
+                } else {
+                    displayRegion.splitHorizontally(topHitRegion, bottomHitRegion);
+                }
 
                 mTargets.add(new Target(TYPE_SPLIT_TOP, topHitRegion, topDrawRegion));
                 mTargets.add(new Target(TYPE_SPLIT_BOTTOM, bottomHitRegion, bottomDrawRegion));
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragLayout.java b/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragLayout.java
index 4d981f6aff50..fd3be2b11c15 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragLayout.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/draganddrop/DragLayout.java
@@ -17,6 +17,7 @@
 package com.android.wm.shell.draganddrop;
 
 import static android.app.StatusBarManager.DISABLE_NONE;
+import static android.view.ViewGroup.LayoutParams.MATCH_PARENT;
 
 import static com.android.wm.shell.common.split.SplitScreenConstants.SPLIT_POSITION_BOTTOM_OR_RIGHT;
 import static com.android.wm.shell.common.split.SplitScreenConstants.SPLIT_POSITION_TOP_OR_LEFT;
@@ -33,11 +34,11 @@ import android.content.Context;
 import android.content.res.Configuration;
 import android.graphics.Color;
 import android.graphics.Insets;
+import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.os.RemoteException;
 import android.view.DragEvent;
 import android.view.SurfaceControl;
-import android.view.ViewGroup;
 import android.view.WindowInsets;
 import android.view.WindowInsets.Type;
 import android.widget.LinearLayout;
@@ -74,6 +75,7 @@ public class DragLayout extends LinearLayout {
     private DropZoneView mDropZoneView2;
 
     private int mDisplayMargin;
+    private int mDividerSize;
     private Insets mInsets = Insets.NONE;
 
     private boolean mIsShowing;
@@ -90,13 +92,15 @@ public class DragLayout extends LinearLayout {
 
         mDisplayMargin = context.getResources().getDimensionPixelSize(
                 R.dimen.drop_layout_display_margin);
+        mDividerSize = context.getResources().getDimensionPixelSize(
+                R.dimen.split_divider_bar_width);
 
         mDropZoneView1 = new DropZoneView(context);
         mDropZoneView2 = new DropZoneView(context);
-        addView(mDropZoneView1, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
-                ViewGroup.LayoutParams.MATCH_PARENT));
-        addView(mDropZoneView2, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
-                ViewGroup.LayoutParams.MATCH_PARENT));
+        addView(mDropZoneView1, new LinearLayout.LayoutParams(MATCH_PARENT,
+                MATCH_PARENT));
+        addView(mDropZoneView2, new LinearLayout.LayoutParams(MATCH_PARENT,
+                MATCH_PARENT));
         ((LayoutParams) mDropZoneView1.getLayoutParams()).weight = 1;
         ((LayoutParams) mDropZoneView2.getLayoutParams()).weight = 1;
         updateContainerMargins();
@@ -184,6 +188,7 @@ public class DragLayout extends LinearLayout {
                 int bgColor1 = getResizingBackgroundColor(taskInfo1);
                 mDropZoneView1.setAppInfo(bgColor1, icon1);
                 mDropZoneView2.setAppInfo(bgColor1, icon1);
+                updateDropZoneSizes(null, null); // passing null splits the views evenly
             }
         } else {
             // We're already in split so get taskInfo from the controller to populate icon / color.
@@ -200,7 +205,45 @@ public class DragLayout extends LinearLayout {
                 mDropZoneView1.setAppInfo(topOrLeftColor, topOrLeftIcon);
                 mDropZoneView2.setAppInfo(bottomOrRightColor, bottomOrRightIcon);
             }
+
+            // Update the dropzones to match existing split sizes
+            Rect topOrLeftBounds = new Rect();
+            Rect bottomOrRightBounds = new Rect();
+            mSplitScreenController.getStageBounds(topOrLeftBounds, bottomOrRightBounds);
+            updateDropZoneSizes(topOrLeftBounds, bottomOrRightBounds);
+        }
+    }
+
+    /**
+     * Sets the size of the two drop zones based on the provided bounds. The divider sits between
+     * the views and its size is included in the calculations.
+     *
+     * @param bounds1 bounds to apply to the first dropzone view, null if split in half.
+     * @param bounds2 bounds to apply to the second dropzone view, null if split in half.
+     */
+    private void updateDropZoneSizes(Rect bounds1, Rect bounds2) {
+        final int orientation = getResources().getConfiguration().orientation;
+        final boolean isPortrait = orientation == Configuration.ORIENTATION_PORTRAIT;
+        final int halfDivider = mDividerSize / 2;
+        final LinearLayout.LayoutParams dropZoneView1 =
+                (LayoutParams) mDropZoneView1.getLayoutParams();
+        final LinearLayout.LayoutParams dropZoneView2 =
+                (LayoutParams) mDropZoneView2.getLayoutParams();
+        if (isPortrait) {
+            dropZoneView1.width = MATCH_PARENT;
+            dropZoneView2.width = MATCH_PARENT;
+            dropZoneView1.height = bounds1 != null ? bounds1.height() + halfDivider : MATCH_PARENT;
+            dropZoneView2.height = bounds2 != null ? bounds2.height() + halfDivider : MATCH_PARENT;
+        } else {
+            dropZoneView1.width = bounds1 != null ? bounds1.width() + halfDivider : MATCH_PARENT;
+            dropZoneView2.width = bounds2 != null ? bounds2.width() + halfDivider : MATCH_PARENT;
+            dropZoneView1.height = MATCH_PARENT;
+            dropZoneView2.height = MATCH_PARENT;
         }
+        dropZoneView1.weight = bounds1 != null ? 0 : 1;
+        dropZoneView2.weight = bounds2 != null ? 0 : 1;
+        mDropZoneView1.setLayoutParams(dropZoneView1);
+        mDropZoneView2.setLayoutParams(dropZoneView2);
     }
 
     public void show() {