Improve automatic synchronization process

src/main/java/com/owncloud/android/syncadapter/FileSyncAdapter.java

@@ -34,8 +34,28 @@
 import android.content.SyncResult;
 import android.os.Bundle;
 import android.support.annotation.PluralsRes;
+import android.preference.PreferenceManager;
 import android.support.v4.app.NotificationCompat;
 
+import com.owncloud.android.R;
+import com.owncloud.android.authentication.AuthenticatorActivity;
+import com.owncloud.android.datamodel.FileDataStorageManager;
+import com.owncloud.android.datamodel.OCFile;
+import com.owncloud.android.lib.common.operations.RemoteOperationResult;
+import com.owncloud.android.lib.common.operations.RemoteOperationResult.ResultCode;
+import com.owncloud.android.lib.common.utils.Log_OC;
+import com.owncloud.android.operations.RefreshFolderOperation;
+import com.owncloud.android.operations.UpdateOCVersionOperation;
+import com.owncloud.android.ui.activity.ErrorsWhileCopyingHandlerActivity;
+
+import org.apache.jackrabbit.webdav.DavException;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
 import com.owncloud.android.R;
 import com.owncloud.android.authentication.AuthenticatorActivity;
 import com.owncloud.android.datamodel.FileDataStorageManager;
@@ -141,15 +161,18 @@ public synchronized void onPerformSync(Account account, Bundle extras,
             String authority, ContentProviderClient providerClient,
             SyncResult syncResult) {
 
+        String timeString = PreferenceManager.getDefaultSharedPreferences(getContext()).getString("time_between_sync", "60");
+        int timeTillNextSyncInMinutes = Integer.parseInt(timeString);
+
         mCancellation = false;
         mFailedResultsCounter = 0;
         mLastFailedResult = null;
         mConflictsFound = 0;
         mFailsInFavouritesFound = 0;
-        mForgottenLocalFiles = new HashMap<String, String>();
+        mForgottenLocalFiles = new HashMap<>();
         mSyncResult = syncResult;
         mSyncResult.fullSyncRequested = false;
-        mSyncResult.delayUntil = (System.currentTimeMillis()/1000) + 3*60*60; // avoid too many automatic synchronizations
+        mSyncResult.delayUntil = (System.currentTimeMillis()/1000) + timeTillNextSyncInMinutes*60; // avoid too many automatic synchronizations
 
         this.setAccount(account);
         this.setContentProviderClient(providerClient);

src/main/java/com/owncloud/android/ui/activity/Preferences.java

@@ -24,6 +24,7 @@
 
 import android.accounts.Account;
 import android.app.Activity;
+import android.content.ContentResolver;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.pm.PackageInfo;
@@ -98,6 +99,7 @@ public class Preferences extends PreferenceActivity
 
     public final static String PREFERENCE_USE_FINGERPRINT = "use_fingerprint";
     public static final String PREFERENCE_EXPERT_MODE = "expert_mode";
+    public static final String PREFERENCE_TIME_BETWEEN_SYNC = "time_between_sync";
 
     private static final int ACTION_REQUEST_PASSCODE = 5;
     private static final int ACTION_CONFIRM_PASSCODE = 6;
@@ -119,6 +121,7 @@ public class Preferences extends PreferenceActivity
     private SwitchPreference mExpertMode;
     private AppCompatDelegate mDelegate;
 
+    private Preference mPrefTimeBetweenSynchronizations;
     private ListPreference mPrefStoragePath;
     private String mStoragePath;
     private String pendingLock;
@@ -179,6 +182,25 @@ public void onCreate(Bundle savedInstanceState) {
         setupDevCategory(accentColor, preferenceScreen);
     }
 
+    @Override
+    protected void onResume() {
+        super.onResume();
+
+        boolean isAutoSyncEnabled = ContentResolver.getSyncAutomatically(
+                AccountUtils.getCurrentOwnCloudAccount(this), getString(R.string.authority));
+        mPrefTimeBetweenSynchronizations.setEnabled(isAutoSyncEnabled);
+        String summary;
+        if (isAutoSyncEnabled) {
+            SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
+            int minutesBetweenSyncs = Integer.parseInt(prefs.getString("time_between_sync", "60"));
+            summary = getResources().getQuantityString(
+                    R.plurals.minutes, minutesBetweenSyncs, minutesBetweenSyncs);
+        } else {
+            summary = getString(R.string.prefs_time_between_sync_sync_disabled);
+        }
+        mPrefTimeBetweenSynchronizations.setSummary(summary);
+    }
+
     private void setupDevCategory(int accentColor, PreferenceScreen preferenceScreen) {
         // Dev category
         PreferenceCategory preferenceCategoryDev = (PreferenceCategory) findPreference("dev_category");
@@ -220,7 +242,6 @@ private void setupAboutCategory(int accentColor, String appVersion) {
         PreferenceCategory preferenceCategoryAbout = (PreferenceCategory) findPreference("about");
         preferenceCategoryAbout.setTitle(ThemeUtils.getColoredTitle(getString(R.string.prefs_category_about),
                 accentColor));
-
         /* About App */
         Preference pAboutApp = findPreference("about_app");
         if (pAboutApp != null) {
@@ -564,11 +585,36 @@ private void setupDetailsCategory(int accentColor, PreferenceScreen preferenceSc
 
         setupExpertModePreference(preferenceCategoryDetails, fSyncedFolderLightEnabled);
 
+        setupTimeBetweenSynchronizationsPreference(preferenceCategoryDetails, fSyncedFolderLightEnabled);
+
         if (!fPassCodeEnabled && !fDeviceCredentialsEnabled && !fShowHiddenFilesEnabled && fSyncedFolderLightEnabled) {
             preferenceScreen.removePreference(preferenceCategoryDetails);
         }
     }
 
+    private void setupTimeBetweenSynchronizationsPreference(
+            PreferenceCategory preferenceCategoryDetails,
+            boolean fSyncedFolderLightEnabled) {
+        mPrefTimeBetweenSynchronizations = findPreference(PREFERENCE_TIME_BETWEEN_SYNC);
+
+        if (fSyncedFolderLightEnabled) {
+            preferenceCategoryDetails.removePreference(mPrefTimeBetweenSynchronizations);
+        } else if (mPrefTimeBetweenSynchronizations != null) {
+            mPrefTimeBetweenSynchronizations.setOnPreferenceChangeListener((preference, newValueObject) -> {
+                if (newValueObject instanceof String && ((String) newValueObject).length() > 0) {
+                    int newValue = Integer.parseInt((String) newValueObject);
+                    if (newValue > 0) {
+                        mPrefTimeBetweenSynchronizations.setSummary(
+                                getResources().getQuantityString(
+                                        R.plurals.minutes, newValue, newValue));
+                        return true;
+                    }
+                }
+                return false;
+            });
+        }
+    }
+
     private void setupExpertModePreference(PreferenceCategory preferenceCategoryDetails,
                                            boolean fSyncedFolderLightEnabled) {
         mExpertMode = (SwitchPreference) findPreference(PREFERENCE_EXPERT_MODE);

src/main/res/values/strings.xml

@@ -443,6 +443,14 @@
 
     <string name="prefs_category_details">Details</string>
 
+
+    <string name="prefs_time_between_sync">Time between synchronization</string>
+    <string name="prefs_time_between_sync_sync_disabled">Automatic synchronization disabled</string>
+    <plurals name="minutes">
+        <item quantity="one">One minute</item>
+        <item quantity="other">%d minutes</item>
+    </plurals>
+
     <string name="sync_folder_failed_content">Sync of %1$s folder could not be completed</string>
 
 	<string name="subject_user_shared_with_you">%1$s shared \"%2$s\" with you</string>

src/main/res/xml/preferences.xml

@@ -50,6 +50,7 @@
 		<com.owncloud.android.ui.ThemeableSwitchPreference
 			android:title="@string/prefs_expert_mode"
 			android:key="expert_mode"/>
+        <android.preference.EditTextPreference android:numeric="integer" android:inputType="number" android:defaultValue="60" android:title="@string/prefs_time_between_sync" android:key="time_between_sync" />
 	</PreferenceCategory>
 
 	<PreferenceCategory android:title="@string/prefs_category_more" android:key="more">