Used Xcode's "Convert to Modern Objective-C syntax"

FSUserDefaults/FSUserDefaults.h

@@ -43,6 +43,6 @@
 @property (nonatomic, strong, readonly) NSUserDefaults *userDefaults;
 
 + (instancetype)sharedInstance;
-- (instancetype)initWithSuiteName:(NSString *)suiteName;
+- (instancetype)initWithSuiteName:(NSString *)suiteName NS_DESIGNATED_INITIALIZER;
 
 @end

QuietUnrarAppDelegate.h

@@ -41,6 +41,6 @@ enum
 - (BOOL) shouldFileBeReplaced:(NSString *) filename;
 - (void) alertUserOfMissing:(const char *) volume;
 - (void) hideDockIcon: (BOOL) hide;
-- (NSString *) requestArchivePassword;
+@property (NS_NONATOMIC_IOSONLY, readonly, copy) NSString *requestArchivePassword;
 
 @end

QuietUnrarAppDelegate.m

@@ -139,7 +139,7 @@ BOOL appRunning = NO;
 
 - (void)applicationWillBecomeActive:(NSNotification *)notification {
     //no use, if app is already running when I try and openfile it is my apps bundle id
-    NSLog(@"%@", [[NSWorkspace sharedWorkspace] frontmostApplication].bundleIdentifier);
+    NSLog(@"%@", [NSWorkspace sharedWorkspace].frontmostApplication.bundleIdentifier);
 }
 
 - (BOOL)application:(id)sender openFileWithoutUI:(NSString *)filename {
@@ -168,10 +168,10 @@ BOOL appRunning = NO;
     NSAlert *alert = [[NSAlert alloc] init];
     [alert addButtonWithTitle:@"Overwrite"];
     NSButton * skipButton = [alert addButtonWithTitle:@"Skip"];
-    [skipButton setKeyEquivalent:@"\e"];
-    [alert setMessageText:[NSString stringWithFormat:@"Overwrite %@?", filename]];
-    [alert setInformativeText:[NSString stringWithFormat:@"The file %@ already exists. Do you wish to extract it again, overwriting the original file?", filename]];
-    [alert setAlertStyle:NSAlertStyleWarning];
+    skipButton.keyEquivalent = @"\e";
+    alert.messageText = [NSString stringWithFormat:@"Overwrite %@?", filename];
+    alert.informativeText = [NSString stringWithFormat:@"The file %@ already exists. Do you wish to extract it again, overwriting the original file?", filename];
+    alert.alertStyle = NSAlertStyleWarning;
 
     if ([alert runModal] == NSAlertFirstButtonReturn) {
         result = YES;
@@ -185,9 +185,9 @@ BOOL appRunning = NO;
 - (void) alertUserOfMissing:(const char *) volume {
     NSAlert *alert = [[NSAlert alloc] init];
     [alert addButtonWithTitle:@"OK"];
-    [alert setMessageText:[NSString stringWithFormat:@"Archive part %s is missing.", volume]];
-    [alert setInformativeText:@"Unable to extract all files from RAR archive as part of it is missing"];
-    [alert setAlertStyle:NSAlertStyleCritical];
+    alert.messageText = [NSString stringWithFormat:@"Archive part %s is missing.", volume];
+    alert.informativeText = @"Unable to extract all files from RAR archive as part of it is missing";
+    alert.alertStyle = NSAlertStyleCritical;
 
     [alert runModal];
 
@@ -202,7 +202,7 @@ BOOL appRunning = NO;
 
         [bundle loadNibNamed:@"PasswordView" owner:self topLevelObjects: nil];
     } else {
-        [passwordField setStringValue:@""];
+        passwordField.stringValue = @"";
     }
 
     NSString * password = nil;
@@ -210,13 +210,13 @@ BOOL appRunning = NO;
     NSAlert *alert = [[NSAlert alloc] init];
     [alert addButtonWithTitle:@"OK"];
     [alert addButtonWithTitle:@"Cancel"];
-    [alert setMessageText:@"Archive Requires a password"];
-    [alert setInformativeText:@"To extract the contents of this archive a password is required."];
-    [alert setAccessoryView:passwordView];
-    [alert setAlertStyle:NSAlertStyleWarning];
+    alert.messageText = @"Archive Requires a password";
+    alert.informativeText = @"To extract the contents of this archive a password is required.";
+    alert.accessoryView = passwordView;
+    alert.alertStyle = NSAlertStyleWarning;
 
     if ([alert runModal] == NSAlertFirstButtonReturn) {
-        password = [passwordField stringValue];
+        password = passwordField.stringValue;
     }
 
     return password;
@@ -241,7 +241,7 @@ BOOL appRunning = NO;
     if (show) {
         statusBarItem = [NSStatusBar.systemStatusBar statusItemWithLength:NSVariableStatusItemLength];
         statusBarItem.button.title = @"🎫"; //RMCG change to something more appropriate
-        [statusBarItem setMenu:[self makeStatusBarMenu]];
+        statusBarItem.menu = [self makeStatusBarMenu];
     } else {
         [NSStatusBar.systemStatusBar removeStatusItem:statusBarItem];
     }
@@ -249,7 +249,7 @@ BOOL appRunning = NO;
 
 - (NSMenu *) makeStatusBarMenu {
     NSMenu * statusBarMenu = [[NSMenu alloc] init];
-    [statusBarMenu setTitle:@"QuietUnarchiver Menu"];
+    statusBarMenu.title = @"QuietUnarchiver Menu";
 
     NSMenuItem * preferencesMenuItem = [[NSMenuItem alloc] initWithTitle:@"Show Preferences" action:@selector(showPreferencesWindow) keyEquivalent:@""];
     [statusBarMenu addItem:preferencesMenuItem];

TDNPreferencesWindowController.m

@@ -24,7 +24,7 @@
 @synthesize userDefaults, showNotificationsSwitch, playSoundSwitch, hideDockIconSwitch;
 @synthesize quietUnrar;
 
-- (id) init {
+- (instancetype) init {
     return [super initWithWindowNibName:@"PreferencesWindow"];
 }
 
@@ -34,31 +34,31 @@
     userDefaults = [TDNUserDefaults sharedInstance];
 
     // Implement this method to handle any initialization after your window controller's window has been loaded from its nib file.
-    [self.window setTitle:@"QuietUnarchiver Preferences"];
+    (self.window).title = @"QuietUnarchiver Preferences";
 
     if (userDefaults.hideDock) {
-        [hideDockIconSwitch setState:NSControlStateValueOn];
+        hideDockIconSwitch.state = NSControlStateValueOn;
     }
 
     if (userDefaults.showNotification) {
-        [showNotificationsSwitch setState:NSControlStateValueOn];
+        showNotificationsSwitch.state = NSControlStateValueOn;
     }
 
     if (userDefaults.playSounds) {
-        [playSoundSwitch setState:NSControlStateValueOn];
+        playSoundSwitch.state = NSControlStateValueOn;
     }
 }
 
 - (IBAction)showNotificationsSwitchToggled:(id)sender {
-    userDefaults.showNotification = [showNotificationsSwitch state];
+    userDefaults.showNotification = showNotificationsSwitch.state;
 }
 
 - (IBAction)playSoundSwitchToggled:(id)sender {
-    userDefaults.playSounds = [playSoundSwitch state];
+    userDefaults.playSounds = playSoundSwitch.state;
 }
 
 - (IBAction)hideDockIconSwitchToggled:(id)sender {
-    userDefaults.hideDock = [hideDockIconSwitch state];
+    userDefaults.hideDock = hideDockIconSwitch.state;
     [quietUnrar hideDockIcon: userDefaults.hideDock];
 }
 

TDNUnarchiver.m

@@ -116,7 +116,7 @@ int CALLBACK generalCallbackFunction(UINT message, LPARAM userData, LPARAM param
 
     //Determine the folder we should extract the archive to. This by default
     //is the <folderContainingTheArchive>/<archiveNameWithPathExtension>
-    NSString * folderToExtractTo = [filename stringByDeletingPathExtension];
+    NSString * folderToExtractTo = filename.stringByDeletingPathExtension;
 
     // Open the Archive for extraction, we set the open result to 3 so we can see it has changed
     char * filenameCString = (char *)[filename cStringUsingEncoding:NSISOLatin1StringEncoding];
@@ -202,7 +202,7 @@ int CALLBACK generalCallbackFunction(UINT message, LPARAM userData, LPARAM param
         }
     }
 
-    NSString * folderToExtractTo = [filename stringByDeletingPathExtension];
+    NSString * folderToExtractTo = filename.stringByDeletingPathExtension;
 
     BOOL extractFilesSuccessful = [archive extractFilesTo: folderToExtractTo
                                                 overwrite:NO