Delay swipe refreshing updates

app/src/main/java/eu/faircode/email/FragmentMessages.java

@@ -213,7 +213,7 @@ import static org.openintents.openpgp.OpenPgpSignatureResult.RESULT_VALID_KEY_UN
 
 public class FragmentMessages extends FragmentBase implements SharedPreferences.OnSharedPreferenceChangeListener {
     private ViewGroup view;
-    private SwipeRefreshLayout swipeRefresh;
+    private SwipeRefreshLayoutEx swipeRefresh;
     private TextView tvSupport;
     private ImageButton ibHintSupport;
     private ImageButton ibHintSwipe;
@@ -1338,16 +1338,15 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
         args.putLong("folder", folder);
         args.putString("type", type);
 
-        new SimpleTask<Integer>() {
+        new SimpleTask<Void>() {
             @Override
-            protected Integer onExecute(Context context, Bundle args) {
+            protected Void onExecute(Context context, Bundle args) {
                 long fid = args.getLong("folder");
                 String type = args.getString("type");
 
                 if (!ConnectionHelper.getNetworkState(context).isSuitable())
                     throw new IllegalStateException(context.getString(R.string.title_no_internet));
 
-                int count;
                 boolean now = true;
                 boolean force = false;
 
@@ -1370,8 +1369,6 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
                             folders.add(folder);
                     }
 
-                    count = folders.size();
-
                     for (EntityFolder folder : folders) {
                         EntityOperation.sync(context, folder.id, true);
 
@@ -1399,13 +1396,7 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
                 if (!now)
                     throw new IllegalArgumentException(context.getString(R.string.title_no_connection));
 
-                return count;
-            }
-
-            @Override
-            protected void onExecuted(Bundle args, Integer count) {
-                if (count > 0)
-                    swipeRefresh.setRefreshing(true);
+                return null;
             }
 
             @Override
@@ -3200,10 +3191,7 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
         adapter.setZoom(zoom);
 
         // Restart spinner
-        if (swipeRefresh.isRefreshing()) {
-            swipeRefresh.setRefreshing(false);
-            swipeRefresh.setRefreshing(true);
-        }
+        swipeRefresh.resetRefreshing();
 
         prefs.registerOnSharedPreferenceChangeListener(this);
         onSharedPreferenceChanged(prefs, "pro");
@@ -3872,7 +3860,6 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
         else
             fabError.hide();
 
-        if (refreshing != swipeRefresh.isRefreshing())
         swipeRefresh.setRefreshing(refreshing);
     }
 

app/src/main/java/eu/faircode/email/SwipeRefreshLayoutEx.java

@@ -0,0 +1,77 @@
+package eu.faircode.email;
+
+/*
+    This file is part of FairEmail.
+
+    FairEmail is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    FairEmail is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with FairEmail.  If not, see <http://www.gnu.org/licenses/>.
+
+    Copyright 2018-2020 by Marcel Bokhorst (M66B)
+*/
+
+import android.content.Context;
+import android.util.AttributeSet;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
+
+public class SwipeRefreshLayoutEx extends SwipeRefreshLayout {
+    private boolean refreshing = false;
+
+    private static final int DELAY_DISABLE = 1000; // milliseconds
+
+    public SwipeRefreshLayoutEx(@NonNull Context context) {
+        super(context);
+    }
+
+    public SwipeRefreshLayoutEx(@NonNull Context context, @Nullable AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    public void setRefreshing(boolean refreshing) {
+        if (this.refreshing == refreshing)
+            return;
+
+        this.refreshing = refreshing;
+
+        removeCallbacks(delayedDisable);
+
+        if (refreshing)
+            super.setRefreshing(refreshing);
+        else
+            postDelayed(delayedDisable, DELAY_DISABLE);
+    }
+
+    @Override
+    public boolean isRefreshing() {
+        return this.refreshing;
+    }
+
+    public void resetRefreshing() {
+        // Restart spinner after screen off, etc
+        if (super.isRefreshing()) {
+            super.setRefreshing(false);
+            super.setRefreshing(true);
+        }
+    }
+
+    private final Runnable delayedDisable = new Runnable() {
+        @Override
+        public void run() {
+            if (!refreshing)
+                SwipeRefreshLayoutEx.super.setRefreshing(refreshing);
+        }
+    };
+}

app/src/main/res/layout/fragment_messages.xml

@@ -6,7 +6,7 @@
     android:layout_height="match_parent"
     tools:context="eu.faircode.email.ActivityView">
 
-    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
+    <eu.faircode.email.SwipeRefreshLayoutEx
         android:id="@+id/swipeRefresh"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
@@ -325,7 +325,7 @@
                 android:layout_height="0dp"
                 app:constraint_referenced_ids="rvMessage" />
         </androidx.constraintlayout.widget.ConstraintLayout>
-    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
+    </eu.faircode.email.SwipeRefreshLayoutEx>
 
     <com.google.android.material.floatingactionbutton.FloatingActionButton
         android:id="@+id/fabMore"