Enabling Dragging for TabGridDialog and TabGridSheet

This CL enables dragging to reorganize tabs in TabGridDialog and
TabGridSheet. It is now behind the flag TabGroupsAndroidUiImprovements.

Bug: 961433
Change-Id: Ib12025fdd1635962cb785399b7f7558d11ce6e58
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1611305
Commit-Queue: Yue Zhang <yuezhanggg@google.com>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659949}

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_groups/TabGroupUtils.java

@@ -12,6 +12,7 @@ import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.feature_engagement.TrackerFactory;
 import org.chromium.chrome.browser.profiles.Profile;
 import org.chromium.chrome.browser.tab.Tab;
+import org.chromium.chrome.browser.tabmodel.TabModel;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorTabObserver;
 import org.chromium.chrome.browser.tasks.tabgroup.TabGroupModelFilter;
@@ -131,4 +132,20 @@ public class TabGroupUtils {
 
         return selector.getCurrentModel().indexOf(tabs.get(tabs.size() - 1));
     }
+
+    /**
+     * This method judges whether the current move from {@code curIndex} to {@code newIndex} in
+     * {@code tabModel} is a move within one TabGroup or not.
+     * @param tabModel   The TabModel that owns the moving tab.
+     * @param curIndex   The current index of the moving tab.
+     * @param newIndex   The new index of the moving tab.
+     * @return Whether is move happens within one TabGroup or not.
+     */
+    public static boolean isMoveInSameGroup(TabModel tabModel, int curIndex, int newIndex) {
+        int rootId = tabModel.getTabAt(curIndex).getRootId();
+        for (int i = Math.min(newIndex, curIndex); i <= Math.max(newIndex, curIndex); i++) {
+            if (tabModel.getTabAt(i).getRootId() != rootId) return false;
+        }
+        return true;
+    }
 }

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListMediator.java

@@ -20,6 +20,7 @@ import android.view.View;
 import org.chromium.base.Callback;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
+import org.chromium.base.VisibleForTesting;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.metrics.RecordUserAction;
 import org.chromium.chrome.browser.native_page.NativePageFactory;
@@ -429,13 +430,25 @@ class TabListMediator {
         // Handle move without groups enabled.
         if (mTabModelSelector.getTabModelFilterProvider().getCurrentTabModelFilter()
                         instanceof EmptyTabModelFilter) {
-            if (mModel.indexFromId(tab.getId()) == TabModel.INVALID_TAB_INDEX) return;
-            if (newIndex >= mModel.size() || curIndex >= mModel.size()) return;
+            if (!isValidMovePosition(curIndex) || !isValidMovePosition(newIndex)) return;
             mModel.move(curIndex, newIndex);
             return;
         }
 
         // Handle move with groups enabled.
+        // When move within one group.
+        if (TabGroupUtils.isMoveInSameGroup(tabModel, curIndex, newIndex)) {
+            int curPosition = mModel.indexFromId(tab.getId());
+            if (!isValidMovePosition(curPosition)) return;
+            Tab destinationTab =
+                    tabModel.getTabAt(newIndex > curIndex ? newIndex - 1 : newIndex + 1);
+            int newPosition = mModel.indexFromId(destinationTab.getId());
+            if (!isValidMovePosition(newPosition)) return;
+            mModel.move(curPosition, newPosition);
+            return;
+        }
+
+        // When move between groups.
         // Only proceed when all members of the group are moved to target index in TabModel.
         // Regardless of the size of tab group, one tab(group) only proceeds once here per
         // move.
@@ -446,7 +459,7 @@ class TabListMediator {
         Tab currentGroupSelectedTab =
                 TabGroupUtils.getSelectedTabInGroupForTab(mTabModelSelector, tab);
         int curPosition = mModel.indexFromId(currentGroupSelectedTab.getId());
-        if (curPosition == TabModel.INVALID_TAB_INDEX || curPosition > mModel.size()) return;
+        if (!isValidMovePosition(curPosition)) return;
 
         // Find the tab which was in the destination index before this move. Use that tab to
         // figure out the new position.
@@ -456,11 +469,15 @@ class TabListMediator {
         Tab destinationGroupSelectedTab =
                 TabGroupUtils.getSelectedTabInGroupForTab(mTabModelSelector, destinationTab);
         int newPosition = mModel.indexFromId(destinationGroupSelectedTab.getId());
-        if (newPosition == TabModel.INVALID_TAB_INDEX || newPosition > mModel.size()) return;
+        if (!isValidMovePosition(newPosition)) return;
 
         mModel.move(curPosition, newPosition);
     }
 
+    private boolean isValidMovePosition(int position) {
+        return position != TabModel.INVALID_TAB_INDEX && position < mModel.size();
+    }
+
     /**
      * Initialize the component with a list of tabs to show in a grid.
      * @param tabs The list of tabs to be shown.
@@ -507,10 +524,16 @@ class TabListMediator {
                         toViewHolder.getAdapterPosition() - fromViewHolder.getAdapterPosition();
                 TabModelFilter filter =
                         mTabModelSelector.getTabModelFilterProvider().getCurrentTabModelFilter();
+                TabModel tabModel = mTabModelSelector.getCurrentModel();
                 if (filter instanceof EmptyTabModelFilter) {
-                    mTabModelSelector.getCurrentModel().moveTab(currentTabId,
+                    tabModel.moveTab(currentTabId,
                             mModel.indexFromId(currentTabId)
                                     + (distance > 0 ? distance + 1 : distance));
+                } else if (!mCloseAllRelatedTabs) {
+                    int destinationIndex =
+                            tabModel.indexOf(mTabModelSelector.getTabById(destinationTabId));
+                    tabModel.moveTab(
+                            currentTabId, distance > 0 ? destinationIndex + 1 : destinationIndex);
                 } else {
                     List<Tab> destinationTabGroup = getRelatedTabsForId(destinationTabId);
                     int newIndex = distance >= 0 ? TabGroupUtils.getLastTabModelIndexForList(
@@ -571,6 +594,11 @@ class TabListMediator {
         ContextUtils.getApplicationContext().registerComponentCallbacks(mComponentCallbacks);
     }
 
+    @VisibleForTesting
+    void setCloseAllRelatedTabs(boolean flag) {
+        mCloseAllRelatedTabs = flag;
+    }
+
     /**
      * Destroy any members that needs clean up.
      */

chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/tab_management/TabListMediatorUnitTest.java

@@ -232,6 +232,7 @@ public class TabListMediatorUnitTest {
     public void sendsMoveTabSignalCorrectlyWithGroup() {
         initAndAssertAllProperties();
 
+        mMediator.setCloseAllRelatedTabs(true);
         doReturn(mTabGroupModelFilter).when(mTabModelFilterProvider).getCurrentTabModelFilter();
 
         mMediator.getItemTouchHelperCallback(0f).onMove(mRecyclerView, mViewHolder1, mViewHolder2);
@@ -239,6 +240,17 @@ public class TabListMediatorUnitTest {
         verify(mTabGroupModelFilter).moveRelatedTabs(eq(TAB1_ID), eq(2));
     }
 
+    @Test
+    public void sendsMoveTabSignalCorrectlyWithinGroup() {
+        initAndAssertAllProperties();
+
+        doReturn(mTabGroupModelFilter).when(mTabModelFilterProvider).getCurrentTabModelFilter();
+
+        mMediator.getItemTouchHelperCallback(0f).onMove(mRecyclerView, mViewHolder1, mViewHolder2);
+
+        verify(mTabModel).moveTab(eq(TAB1_ID), eq(2));
+    }
+
     @Test
     public void tabClosure() {
         initAndAssertAllProperties();
@@ -458,6 +470,50 @@ public class TabListMediatorUnitTest {
         assertThat(mModel.get(0).get(TabProperties.TITLE), equalTo(TAB2_TITLE));
     }
 
+    @Test
+    public void tabMovementWithinGroup_Forward() {
+        initAndAssertAllProperties();
+
+        // Assume that moveTab in TabModel is finished.
+        doReturn(mTab1).when(mTabModel).getTabAt(POSITION2);
+        doReturn(mTab2).when(mTabModel).getTabAt(POSITION1);
+        doReturn(mTabGroupModelFilter).when(mTabModelFilterProvider).getCurrentTabModelFilter();
+        doReturn(TAB1_ID).when(mTab1).getRootId();
+        doReturn(TAB1_ID).when(mTab2).getRootId();
+
+        assertThat(mModel.size(), equalTo(2));
+        assertThat(mModel.get(1).get(TabProperties.TAB_ID), equalTo(TAB2_ID));
+        assertThat(mModel.get(1).get(TabProperties.TITLE), equalTo(TAB2_TITLE));
+
+        mTabModelObserverCaptor.getValue().didMoveTab(mTab2, POSITION1, POSITION2);
+
+        assertThat(mModel.size(), equalTo(2));
+        assertThat(mModel.get(0).get(TabProperties.TAB_ID), equalTo(TAB2_ID));
+        assertThat(mModel.get(0).get(TabProperties.TITLE), equalTo(TAB2_TITLE));
+    }
+
+    @Test
+    public void tabMovementWithinGroup_Backward() {
+        initAndAssertAllProperties();
+
+        // Assume that moveTab in TabModel is finished.
+        doReturn(mTab1).when(mTabModel).getTabAt(POSITION2);
+        doReturn(mTab2).when(mTabModel).getTabAt(POSITION1);
+        doReturn(mTabGroupModelFilter).when(mTabModelFilterProvider).getCurrentTabModelFilter();
+        doReturn(TAB1_ID).when(mTab1).getRootId();
+        doReturn(TAB1_ID).when(mTab2).getRootId();
+
+        assertThat(mModel.size(), equalTo(2));
+        assertThat(mModel.get(1).get(TabProperties.TAB_ID), equalTo(TAB2_ID));
+        assertThat(mModel.get(1).get(TabProperties.TITLE), equalTo(TAB2_TITLE));
+
+        mTabModelObserverCaptor.getValue().didMoveTab(mTab1, POSITION2, POSITION1);
+
+        assertThat(mModel.size(), equalTo(2));
+        assertThat(mModel.get(0).get(TabProperties.TAB_ID), equalTo(TAB2_ID));
+        assertThat(mModel.get(0).get(TabProperties.TITLE), equalTo(TAB2_TITLE));
+    }
+
     private void initAndAssertAllProperties() {
         List<Tab> tabs = new ArrayList<>();
         for (int i = 0; i < mTabModel.getCount(); i++) {