Code improvements final steps

Discussion: #18

Author: purejava

src/main/java/org/cryptomator/linux/tray/AppindicatorTrayMenuController.java

@@ -10,10 +10,12 @@
 import org.cryptomator.integrations.tray.TrayMenuController;
 import org.cryptomator.integrations.tray.TrayMenuException;
 import org.cryptomator.integrations.tray.TrayMenuItem;
+import org.purejava.appindicator.GCallback;
 import org.purejava.appindicator.MemoryAllocator;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.lang.foreign.Arena;
 import java.lang.foreign.MemorySegment;
 import java.lang.foreign.SegmentScope;
 import java.util.List;
@@ -46,9 +48,11 @@ public void showTrayIcon(Consumer<TrayIconLoader> iconLoader, Runnable runnable,
 	}
 
 	private void showTrayIconWithSVG(String s) {
-		indicator = app_indicator_new(MemoryAllocator.ALLOCATE_FOR("org.cryptomator.Cryptomator"),
-				MemoryAllocator.ALLOCATE_FOR(s),
-				APP_INDICATOR_CATEGORY_APPLICATION_STATUS());
+		try (var arena = Arena.openConfined()) {
+			indicator = app_indicator_new(arena.allocateUtf8String("org.cryptomator.Cryptomator"),
+					arena.allocateUtf8String(s),
+					APP_INDICATOR_CATEGORY_APPLICATION_STATUS());
+		}
 	}
 
 	@Override
@@ -58,7 +62,9 @@ public void updateTrayIcon(Consumer<TrayIconLoader> iconLoader) {
 	}
 
 	private void updateTrayIconWithSVG(String s) {
-		app_indicator_set_icon(indicator, MemoryAllocator.ALLOCATE_FOR(s));
+		try (var arena = Arena.openConfined()) {
+			app_indicator_set_icon(indicator, arena.allocateUtf8String(s));
+		}
 	}
 
 	@Override
@@ -79,12 +85,14 @@ private void addChildren(MemorySegment menu, List<TrayMenuItem> items) {
 			switch (item) {
 				case ActionItem a -> {
 					var gtkMenuItem = gtk_menu_item_new();
-					gtk_menu_item_set_label(gtkMenuItem, MemoryAllocator.ALLOCATE_FOR(a.title()));
-					g_signal_connect_object(gtkMenuItem,
-							MemoryAllocator.ALLOCATE_FOR("activate"),
-							MemoryAllocator.ALLOCATE_CALLBACK_FOR(new ActionItemCallback(a), SCOPE),
-							menu,
-							0);
+					try (var arena = Arena.openConfined()) {
+						gtk_menu_item_set_label(gtkMenuItem, arena.allocateUtf8String(a.title()));
+						g_signal_connect_object(gtkMenuItem,
+								arena.allocateUtf8String("activate"),
+								GCallback.allocate(new ActionItemCallback(a), SCOPE),
+								menu,
+								0);
+					}
 					gtk_menu_shell_append(menu, gtkMenuItem);
 				}
 				case SeparatorItem separatorItem -> {
@@ -94,7 +102,9 @@ private void addChildren(MemorySegment menu, List<TrayMenuItem> items) {
 				case SubMenuItem s -> {
 					var gtkMenuItem = gtk_menu_item_new();
 					var gtkSubmenu = gtk_menu_new();
-					gtk_menu_item_set_label(gtkMenuItem, MemoryAllocator.ALLOCATE_FOR(s.title()));
+					try (var arena = Arena.openConfined()) {
+						gtk_menu_item_set_label(gtkMenuItem, arena.allocateUtf8String(s.title()));
+					}
 					addChildren(gtkSubmenu, s.items());
 					gtk_menu_item_set_submenu(gtkMenuItem, gtkSubmenu);
 					gtk_menu_shell_append(menu, gtkMenuItem);