blacklist: fix emptying list

This commit fixes a bug when unblocking the last contact in the black 
list fragment.

The empty message was not displayed in the UI thread.

Change-Id: I2b3f033550d30d5466e58edcd556f38d39abcfac
Tuleap: #1500
Reviewed-by: Aline Bonnet <aline.bonnet@savoirfairelinux.com>

ring-android/app/src/main/java/cx/ring/contactrequests/BlackListFragment.java

@@ -116,9 +116,10 @@ public class BlackListFragment extends BaseFragment<BlackListPresenter> implemen
 
     @Override
     public void updateView(final ArrayList<BlackListViewModel> list) {
-        RingApplication.uiHandler.post(new Runnable() {
+        getActivity().runOnUiThread(new Runnable() {
             @Override
             public void run() {
+                mBlacklist.setVisibility(View.VISIBLE);
                 if (mBlacklist.getAdapter() != null) {
                     mAdapter.replaceAll(list);
                 } else {
@@ -132,7 +133,22 @@ public class BlackListFragment extends BaseFragment<BlackListPresenter> implemen
     }
 
     @Override
-    public void displayEmptyListMessage(boolean display) {
-        mEmptyTextView.setVisibility(display? View.VISIBLE : View.GONE);
+    public void hideListView() {
+        getActivity().runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                mBlacklist.setVisibility(View.GONE);
+            }
+        });
+    }
+
+    @Override
+    public void displayEmptyListMessage(final boolean display) {
+        getActivity().runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                mEmptyTextView.setVisibility(display ? View.VISIBLE : View.GONE);
+            }
+        });
     }
 }
\ No newline at end of file

ring-android/libringclient/src/main/java/cx/ring/contactrequests/BlackListPresenter.java

@@ -91,6 +91,7 @@ public class BlackListPresenter extends RootPresenter<BlackListView> implements
         }
 
         if(mViewModels.isEmpty()) {
+            getView().hideListView();
             getView().displayEmptyListMessage(true);
         } else {
             getView().updateView(mViewModels);

ring-android/libringclient/src/main/java/cx/ring/contactrequests/BlackListView.java

@@ -25,5 +25,7 @@ public interface BlackListView {
 
     void updateView(ArrayList<BlackListViewModel> list);
 
+    void hideListView();
+
     void displayEmptyListMessage(boolean display);
 }