altosdroid: Safeguard preferences code in case it's called too early

Make sure there's a backend set up before accessing data as it seems
this code can be called before the preferences code is called before
the backend is created.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/altosdroid/app/src/main/java/org/altusmetrum/AltosDroid/AltosDroidPreferences.java b/altosdroid/app/src/main/java/org/altusmetrum/AltosDroid/AltosDroidPreferences.java
index f49f11004a30c419da4b311abe36d110064bfce5..4d9204d9ac79c71b210e3a53d54467d999a6aa0f 100644 (file)
--- a/altosdroid/app/src/main/java/org/altusmetrum/AltosDroid/AltosDroidPreferences.java
+++ b/altosdroid/app/src/main/java/org/altusmetrum/AltosDroid/AltosDroidPreferences.java
@@ -72,6 +72,8 @@ public class AltosDroidPreferences extends AltosPreferences {
        }
 
        public static void set_active_device(DeviceAddress address) {
+               if (backend == null)
+                       return;
                synchronized(backend) {
                        active_device_address = address;
                        if (active_device_address != null) {
@@ -86,6 +88,9 @@ public class AltosDroidPreferences extends AltosPreferences {
        }
 
        public static DeviceAddress active_device() {
+               if (backend == null)
+                       return null;
+
                synchronized(backend) {
                        return active_device_address;
                }
@@ -94,6 +99,8 @@ public class AltosDroidPreferences extends AltosPreferences {
        static LinkedList<AltosDroidMapSourceListener> map_source_listeners;
 
        public static void set_map_source(int map_source) {
+               if (backend == null)
+                       return;
                synchronized(backend) {
                        AltosDroidPreferences.map_source = map_source;
                        backend.putInt(mapSourcePreference, map_source);
@@ -107,12 +114,17 @@ public class AltosDroidPreferences extends AltosPreferences {
        }
 
        public static int map_source() {
+               if (backend == null)
+                       return MAP_SOURCE_ONLINE;
                synchronized(backend) {
                        return map_source;
                }
        }
 
        public static void register_map_source_listener(AltosDroidMapSourceListener l) {
+               if (backend == null)
+                       return;
+
                synchronized(backend) {
                        if (map_source_listeners == null)
                                map_source_listeners = new LinkedList<AltosDroidMapSourceListener>();
@@ -121,18 +133,25 @@ public class AltosDroidPreferences extends AltosPreferences {
        }
 
        public static void unregister_map_source_listener(AltosDroidMapSourceListener l) {
+               if (backend == null)
+                       return;
                synchronized(backend) {
                        map_source_listeners.remove(l);
                }
        }
 
        public static int font_size() {
+               if (backend == null)
+                       return font_size_medium;
+
                synchronized (backend) {
                        return font_size;
                }
        }
 
        public static void set_font_size(int new_font_size) {
+               if (backend == null)
+                       return;
                synchronized (backend) {
                        if (font_size != new_font_size) {
                                font_size = new_font_size;
@@ -144,12 +163,18 @@ public class AltosDroidPreferences extends AltosPreferences {
 
 
        public static int tracker_sort() {
+               if (backend == null)
+                       return 0;
+
                synchronized(backend) {
                        return tracker_sort;
                }
        }
 
        public static void set_tracker_sort(int new_tracker_sort) {
+               if (backend == null)
+                       return;
+
                synchronized(backend) {
                        if (tracker_sort != new_tracker_sort) {
                                tracker_sort = new_tracker_sort;