get rid of listener between tab manager and presenter. invert the dependency between them.

app/src/main/java/acr/browser/lightning/activity/BrowserActivity.java

@@ -948,7 +948,7 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
      */
     // TODO move to presenter
     private synchronized void showTab(final int position) {
-        mTabsManager.switchToTab(position);
+        mPresenter.tabChanged(position);
     }
 
     private static void removeViewFromParent(@Nullable View view) {
@@ -1107,6 +1107,8 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
     protected void onDestroy() {
         Log.d(Constants.TAG, "onDestroy");
 
+        mPresenter.shutdown();
+
         if (mHistoryDatabase != null) {
             mHistoryDatabase.close();
             mHistoryDatabase = null;

app/src/main/java/acr/browser/lightning/activity/TabsManager.java

@@ -45,28 +45,9 @@ public class TabsManager {
     @Inject Bus mEventBus;
     @Inject Application mApp;
 
-    @Nullable private TabChangeListener mListener;
-
-    public interface TabChangeListener {
-        void tabChanged(LightningView newTab);
-    }
-
     @Inject
     public TabsManager() {}
 
-    /**
-     * Sets the {@link TabChangeListener} to a new
-     * listener. Can be set to null if the caller
-     * wishes to unregister the listener.
-     *
-     * @param listener the new listener to use or
-     *                 null if the caller wishes to
-     *                 unregister the listener.
-     */
-    public void setTabChangeListener(@Nullable TabChangeListener listener) {
-        mListener = listener;
-    }
-
     /**
      * Restores old tabs that were open before the browser
      * was closed. Handles the intent used to open the browser.
@@ -156,7 +137,6 @@ public class TabsManager {
      * released for garbage collection.
      */
     public synchronized void shutdown() {
-        sendTabChangedEvent(null);
         for (LightningView tab : mTabList) {
             tab.onDestroy();
         }
@@ -247,7 +227,7 @@ public class TabsManager {
      *
      * @param position the position of the tab to delete.
      */
-    public synchronized void deleteTab(int position) {
+    public synchronized boolean deleteTab(int position) {
         Log.d(TAG, "Delete tab: " + position);
         final LightningView currentTab = getCurrentTab();
         int current = positionOf(currentTab);
@@ -261,10 +241,11 @@ public class TabsManager {
             } else {
                 mCurrentTab = getTabAtPosition(current - 1);
             }
-            sendTabChangedEvent(mCurrentTab);
             removeTab(current);
+            return true;
         } else {
             removeTab(position);
+            return false;
         }
     }
 
@@ -333,6 +314,16 @@ public class TabsManager {
         return mCurrentTab != null ? mCurrentTab.getWebView() : null;
     }
 
+    /**
+     * Returns the index of the current tab.
+     *
+     * @return Return the index of the current tab, or -1 if the
+     * current tab is null.
+     */
+    public int indexOfCurrentTab() {
+        return mTabList.indexOf(mCurrentTab);
+    }
+
     /**
      * Return the current {@link LightningView} or null if
      * no current tab has been set.
@@ -356,32 +347,14 @@ public class TabsManager {
         Log.d(TAG, "switch to tab: " + position);
         if (position < 0 || position >= mTabList.size()) {
             Log.e(TAG, "Returning a null LightningView requested for position: " + position);
-            sendTabChangedEvent(null);
             return null;
         } else {
             final LightningView tab = mTabList.get(position);
             if (tab != null) {
                 mCurrentTab = tab;
             }
-            sendTabChangedEvent(tab);
             return tab;
         }
     }
 
-    /**
-     * Send the event that the current tab has changed to
-     * a new tab to the {@link TabChangeListener} if it is
-     * not null.
-     *
-     * @param newView the new tab that we have switcted to,
-     *                can be null if the last tab has been
-     *                deleted.
-     */
-    private void sendTabChangedEvent(@Nullable LightningView newView) {
-        Log.d(TAG, "NULL: " + (mListener == null));
-        if (mListener != null) {
-            mListener.tabChanged(newView);
-        }
-    }
-
 }

app/src/main/java/acr/browser/lightning/browser/BrowserPresenter.java

@@ -13,7 +13,6 @@ import javax.inject.Inject;
 
 import acr.browser.lightning.R;
 import acr.browser.lightning.activity.TabsManager;
-import acr.browser.lightning.activity.TabsManager.TabChangeListener;
 import acr.browser.lightning.app.BrowserApp;
 import acr.browser.lightning.bus.BrowserEvents;
 import acr.browser.lightning.constant.Constants;
@@ -40,25 +39,10 @@ public class BrowserPresenter {
     private boolean mIsIncognito;
     private boolean mIsNewIntent;
 
-    private static class TabListener implements TabChangeListener {
-
-        private BrowserPresenter mPresenter;
-
-        public TabListener(@NonNull BrowserPresenter presenter) {
-            mPresenter = presenter;
-        }
-
-        @Override
-        public void tabChanged(@Nullable LightningView newTab) {
-            mPresenter.onTabChanged(newTab);
-        }
-    }
-
     public BrowserPresenter(@NonNull BrowserView view, boolean isIncognito) {
         BrowserApp.getAppComponent().inject(this);
         mView = view;
         mIsIncognito = isIncognito;
-        mTabsModel.setTabChangeListener(new TabListener(this));
     }
 
     private void onTabChanged(@Nullable LightningView newTab) {
@@ -115,7 +99,10 @@ public class BrowserPresenter {
             if (isShown) {
                 mView.removeTabView();
             }
-            mTabsModel.deleteTab(position);
+            boolean currentDeleted = mTabsModel.deleteTab(position);
+            if (currentDeleted) {
+                tabChanged(mTabsModel.indexOfCurrentTab());
+            }
         }
         final LightningView afterTab = mTabsModel.getCurrentTab();
         if (afterTab == null) {
@@ -178,6 +165,18 @@ public class BrowserPresenter {
         currentTab.loadUrl(url);
     }
 
+    public void shutdown() {
+        onTabChanged(null);
+    }
+
+    public void tabChanged(int position) {
+        if (position < 0) {
+            return;
+        }
+        LightningView tab = mTabsModel.switchToTab(position);
+        onTabChanged(tab);
+    }
+
     public synchronized boolean newTab(String url, boolean show) {
         // Limit number of tabs for limited version of app
         if (!Constants.FULL_VERSION && mTabsModel.size() >= 10) {
@@ -191,7 +190,8 @@ public class BrowserPresenter {
         }
 
         if (show) {
-            mTabsModel.switchToTab(mTabsModel.size() - 1);
+            LightningView tab = mTabsModel.switchToTab(mTabsModel.size() - 1);
+            onTabChanged(tab);
         }
 
         // TODO Restore this
@@ -205,8 +205,4 @@ public class BrowserPresenter {
         return true;
     }
 
-    public void destroy() {
-        mTabsModel.setTabChangeListener(null);
-    }
-
 }