I have an NSButton in my preferences to interact with adding the application to the LoginItems. If the adding of the login item fails, I want to uncheck the box so the user doesn't get a false sense that it was added to the login items. However, after doing this, when I click the checkbox again, the bindings is not triggered.
- (void)addLoginItem:(BOOL)status
{
NSURL *url = [[[NSBundle mainBundle] bundleURL] URLByAppendingPathComponent:
#"Contents/Library/LoginItems/HelperApp.app"];
// Registering helper app
if (LSRegisterURL((__bridge CFURLRef)url, true) != noErr) {
NSLog(#"LSRegisterURL failed!");
}
if (!SMLoginItemSetEnabled((__bridge CFStringRef)[[NSBundle mainBundle] bundleIdentifier], (status) ? true : false)) {
NSLog(#"SMLoginItemSetEnabled failed!");
[self willChangeValueForKey:#"startAtLogin"];
[self.startAtLogin setValue:[NSNumber numberWithBool:[self automaticStartup]] forKey:#"state"];
[self didChangeValueForKey:#"startAtLogin"];
}
}
- (void)setAutomaticStartup:(BOOL)state
{
NSLog(#"Set automatic startup: %d", state);
if ([self respondsToSelector:#selector(addLoginItem:)]) {
[self addLoginItem:state];
}
}
- (BOOL)automaticStartup
{
BOOL isEnabled = NO;
// the easy and sane method (SMJobCopyDictionary) can pose problems when sandboxed. -_-
CFArrayRef cfJobDicts = SMCopyAllJobDictionaries(kSMDomainUserLaunchd);
NSArray* jobDicts = CFBridgingRelease(cfJobDicts);
if (jobDicts && [jobDicts count] > 0) {
for (NSDictionary* job in jobDicts) {
if ([[[NSBundle mainBundle] bundleIdentifier] isEqualToString:[job objectForKey:#"Label"]]) {
isEnabled = [[job objectForKey:#"OnDemand"] boolValue];
break;
}
}
}
NSLog(#"Is Enabled: %d", isEnabled);
// if (isEnabled != _enabled) {
[self willChangeValueForKey:#"startupEnabled"];
startupEnabled = isEnabled;
[self didChangeValueForKey:#"startupEnabled"];
// }
return isEnabled;
}
I have my databinding for the checkbox bound to self.automaticStartup. If I remove the line [self.startAtLogin setValue:[NSNumber numberWithBool:[self automaticStartup]] forKey:#"state"]; then the bindings work fine, but it doesn't uncheck, if the adding of the item fails.
How can I change this binding value programmatically so that every other binding event is not ignored?
From your explanation, your bound value is automaticStartup, but you are sending willChangeValueForKey: for startAtLogin. In order for bindings to work correctly, you need to alert on the change to the bound variable at some point. However, since you are in the midst of setAutomaticStartup: at the time, it's not really safe to do that here.
In this case, I would not use bindings to perform the change itself, I would consider the old-style IBAction mechanism and then set the checkbox value manually through an IBOutlet when you can confirm the status.
Related
I have a core data application with an NSTableView bound to an NSArrayController. I manage adding and removing objects using the array controller. I'm trying to add undo/redo support so when a person deletes an object from the table view, using a menu item, they can undo the delete.
My delete method is:
- (IBAction)removeHost:(id)sender
{
NSInteger row = [bookmarkList selectedRow];
// Get the object so we can get to the attributes of the host
NSArray *a = [bookmarksController arrangedObjects];
NSManagedObject *object = [a objectAtIndex:row];
if (!object) return;
NSManagedObjectContext *managedObjectContext = [self managedObjectContext];
NSUndoManager *undoManager = [managedObjectContext undoManager];
if (managedObjectContext.undoManager == nil)
{
NSLog(#"No undo manager in app controller!");
} else {
NSLog(#"We've got an undo manager in app controller!");
}
[undoManager registerUndoWithTarget:self selector:#selector(addBookmarkObject:) object:object];
[bookmarksController removeObject:object];
[undoManager setActionName:#"Bookmark Delete"];
}
Deleting the object works fine, but undo does not. The Command-Z menu item is never enabled. I setup a temporary menu item and action to test the undoManager,
- (IBAction)stupidUndoRemoveHost:(id)sender
{
NSManagedObjectContext *managedObjectContext = [self managedObjectContext];
NSUndoManager *undoer = [managedObjectContext undoManager];
NSLog(#"canUndo? %hhd", [undoer canUndo]);
NSLog(#"canRedo? %hhd", [undoer canRedo]);
NSLog(#"isUndoRegistrationEnabled? %hhd", [undoer isUndoRegistrationEnabled]);
NSLog(#"undoMenuItemTitle = %#", [undoer undoMenuItemTitle]);
NSLog(#"redoMenuItemTitle = %#", [undoer redoMenuItemTitle]);
[undoer undo];
}
Using this IBAction I can do the undo (well, sort of, it adds the object twice so clearly there's still more wrong here), but I can only do it once. If I delete another object canUndo returns 0, and stupidUndoRemoveHost does nothing.
I know I'm not understanding something here. I've read through more posts here than I can count, several blog posts, and the Apple documentation. I've done this before, but it was like ten years ago, so my skills are a bit rusty. Any help or pointers in the right direction are greatly appreciated.
Update: here is the addBookmarkObject method:
- (void)addBookmarkObject: (NSManagedObject *)object
{
[bookmarksController addObject:object];
}
And here is windowWillReturnUndoManager from the AppDelegate:
- (NSUndoManager *)windowWillReturnUndoManager:(NSWindow *)window {
// Returns the NSUndoManager for the application. In this case, the manager returned is that of the managed object context for the application.
NSUndoManager *undoManager = [[NSUndoManager alloc] init];
self.persistentContainer.viewContext.undoManager = undoManager;
if (self.persistentContainer.viewContext.undoManager == nil)
{
NSLog(#"No undo manager!");
} else {
NSLog(#"We've got an undo manager!");
}
return self.persistentContainer.viewContext.undoManager;
}
windowWillReturnUndoManager: is called every time Appkit wants to register an undo operation and when it wants to enable/disable the Undo menu item. If windowWillReturnUndoManager: returns a new undo manager then the undo stack is empty and the Undo menu item is disabled.
Core Data will register an undo operation when an object is removed, removeHost: shouldn't register an extra undo operation.
- (IBAction)removeHost:(id)sender
{
[bookmarksController remove:sender];
[undoManager setActionName:#"Bookmark Delete"];
}
The Xcode macOS Cocoa App with Core Data template has some flaws.
NSWindowDelegate method windowWillReturnUndoManager: isn't called because in the xib, the delegate of the window isn't connected to the app delegate. Fix: connect the delegate of the window to the Delegate.
self.persistentContainer.viewContext.undoManager is nil. Fix: create the undo manager once when the persistent container is created.
- (NSPersistentContainer *)persistentContainer {
// The persistent container for the application. This implementation creates and returns a container, having loaded the store for the application to it.
#synchronized (self) {
if (_persistentContainer == nil) {
_persistentContainer = [[NSPersistentContainer alloc] initWithName:#"TestCDUndo"];
[_persistentContainer loadPersistentStoresWithCompletionHandler:^(NSPersistentStoreDescription *storeDescription, NSError *error) {
if (error != nil) {
…
abort();
}
self->_persistentContainer.viewContext.undoManager = [[NSUndoManager alloc] init];
}];
}
}
return _persistentContainer;
}
NSDocument continues to be a software maintenance nightmare.
Anyone else having a problem where they want certain blocking dialogs to be handled SYNCHRONOUSLY?
BEGIN EDIT: I may have found a solution that allows me to wait synchronously
Can anyone verify that this would be an "Apple approved" solution?
static BOOL sWaitingForDidSaveModally = NO;
BOOL gWaitingForDidSaveCallback = NO; // NSDocument dialog calls didSave: when done
...
gWaitingForDidSaveCallback = true;
[toDocument saveDocumentWithDelegate:self
didSaveSelector:#selector(document:didSave:contextInfo:)
contextInfo:nil];
if ( gWaitingForDidSaveCallback )
{
// first, dispatch any other potential alerts synchronously
while ( gWaitingForDidSaveCallback && [NSApp modalWindow] )
[NSApp runModalForWindow: [NSApp modalWindow]];
if ( gWaitingForDidSaveCallback )
{
sWaitingForDidSaveModally = YES;
[NSApp runModalForWindow: [NSApp mbWindow]]; // mbWindow is our big (singleton) window
sWaitingForDidSaveModally = NO;
}
}
...
- (void)document:(NSDocument *)doc didSave:(BOOL)didSave contextInfo:(void *)contextInfo
{
[self recordLastSaveURL];
gWaitingForDidSaveCallback = NO;
if ( sWaitingForDidSaveModally )
[NSApp stopModal];
}
END EDIT
I have to support Snow Leopard/Lion/ML
App termination is an ugly process.
When the user decides to quit, and the document has changes that need saving, I call this:
gWaitingForDidSaveCallback = true;
[toDocument saveDocumentWithDelegate:self
didSaveSelector:#selector(document:didSave:contextInfo:)
contextInfo:nil];
I really really really want this call to be synchronous, but in latest Lion, this hangs my app:
while ( gWaitingForDidSaveCallback )
{
// didSave: callback clears sWaitingForDidSaveCallback
// do my own synchronous wait for now
[[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceReferenceDate:0.05]];
}
My best guess for the hang is that the mouseDown: of a window close button
is confusing the NSDocument.
So now, I have to return, and pepper my apps main loop with unmaintainable state machine logic to prevent user from executing various dangerous hotkeys.
Ok, so I grin and bear it, and run into yet another roadblock!
In previous OS versions/SDKs, [NSApp modalWindow] would return a window when it
was in this state. Now it doesn't! Grrrrr...
NSDocument has no API to test when it is in this state!
So, now there is no mechanism to globally check this state!
I have to add yet another state variable to my state machine.
Anyone have a cleaner solution for this problem that works in all OS versions and all present (and future) SDKs?
The better way is to save unsaved documents in chain. It is very easy:
// Catch application terminate event
-(NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender
{
NSDocumentController *dc = [NSDocumentController sharedDocumentController];
for (NSInteger i = 0; i < [[dc documents] count]; i++)
{
Document *doc = [[dc documents] objectAtIndex:i];
if ([doc isDocumentEdited])
{
// Save first unsaved document
[doc saveDocumentWithDelegate:self
didSaveSelector:#selector(document:didSave:contextInfo:)
contextInfo:(__bridge void *)([NSNumber numberWithInteger:i + 1])]; // Next document
return NSTerminateLater; // Wait until last document in chain will be saved
}
}
return NSTerminateNow; // All documents are saved or there are no open documents. Terminate.
}
...
// Document saving finished
-(void)document:(NSDocument *)doc didSave:(BOOL)didSave contextInfo:(void *)contextInfo
{
if (didSave) // Save button pressed
{
NSDocumentController *dc = [NSDocumentController sharedDocumentController];
NSInteger nextIndex = [(__bridge NSNumber *)contextInfo integerValue];
for (NSInteger i = nextIndex; i < [[dc documents] count]; i++)
{
Document *doc = [[dc documents] objectAtIndex:nextIndex];
if ([doc isDocumentEdited])
{
// Save next unsaved document
[doc saveDocumentWithDelegate:self
didSaveSelector:#selector(document:didSave:contextInfo:)
contextInfo:(__bridge void *)([NSNumber numberWithInteger:nextIndex + 1])]; // Next document
return;
}
}
[NSApp replyToApplicationShouldTerminate:YES]; // All documents saved. Terminate.
}
else [NSApp replyToApplicationShouldTerminate:NO]; // Saving canceled. Terminate canceled.
}
Maybe this answer is too late to be useful but... In one of my apps I implemented -(IBAction)terminate:(id)sender in my NSApplication derived class which would conditionally call [super terminate] to actually close the application only if all open documents were cleanly saved. I may have found some of this in the Apple docs or other examples.
The terminate override will go through each document and either close it (because it's saved), or call the document's canCloseDocumentWithDelegate method in the NSDocument derived class passing 'self' and 'terminate' as the didSaveSelector. Since the terminate method falls through and does nothing except make the document present an NSAlert, the alert in the document class will callback and re-run the terminate routine if the user clicks YES or NO. If all documents are clean, the app will terminate since [super terminate] will get called. If any more dirty documents exist, the process repeats.
For example:
#interface MyApplication : NSApplication
#end
#implementation MyApplication
- (IBAction)terminate:(id)sender
{
//Loop through and find any unsaved document to warn the user about.
//Close any saved documents along the way.
NSDocument *docWarn = NULL;
NSArray *documents = [[NSDocumentController sharedDocumentController] documents];
for(int i = 0; i < [documents count]; i++)
{
NSDocument *doc = [documents objectAtIndex:i];
if([doc isDocumentEdited])
{
if(docWarn == NULL || [[doc windowForSheet] isKeyWindow])
docWarn = doc;
}
else
{
//close any document that doesn't need saving. this will
//also close anything that was dirty that the user answered
//NO to on the previous call to this routine which triggered
//a save prompt.
[doc close];
}
}
if(docWarn != NULL)
{
[[docWarn windowForSheet] orderFront:self];
[[docWarn windowForSheet] becomeFirstResponder];
[docWarn canCloseDocumentWithDelegate:self shouldCloseSelector:#selector(terminate:) contextInfo:NULL];
}
else
{
[super terminate:sender];
}
}
#end
Later in the document derived class:
typedef struct {
void * delegate;
SEL shouldCloseSelector;
void *contextInfo;
} CanCloseAlertContext;
#interface MyDocument : NSDocument
#end
#implementation MyDocument
- (void)canCloseDocumentWithDelegate:(id)inDelegate shouldCloseSelector:(SEL)inShouldCloseSelector contextInfo:(void *)inContextInfo
{
// This method may or may not have to actually present the alert sheet.
if (![self isDocumentEdited])
{
// There's nothing to do. Tell the delegate to continue with the close.
if (inShouldCloseSelector)
{
void (*callback)(id, SEL, NSDocument *, BOOL, void *) = (void (*)(id, SEL, NSDocument *, BOOL, void *))objc_msgSend;
(callback)(inDelegate, inShouldCloseSelector, self, YES, inContextInfo);
}
}
else
{
NSWindow *documentWindow = [self windowForSheet];
// Create a record of the context in which the panel is being
// shown, so we can finish up when it's dismissed.
CanCloseAlertContext *closeAlertContext = malloc(sizeof(CanCloseAlertContext));
closeAlertContext->delegate = (__bridge void *)inDelegate;
closeAlertContext->shouldCloseSelector = inShouldCloseSelector;
closeAlertContext->contextInfo = inContextInfo;
// Present a "save changes?" alert as a document-modal sheet.
[documentWindow makeKeyAndOrderFront:nil];
NSBeginAlertSheet(#"Would you like to save your changes?", #"Yes", #"Cancel", #"No", documentWindow, self,
#selector(canCloseAlertSheet:didEndAndReturn:withContextInfo:), NULL, closeAlertContext, #"%");
}
}
- (void)canCloseAlertSheet:(NSWindow *)inAlertSheet didEndAndReturn:(int)inReturnCode withContextInfo:(void *)inContextInfo
{
CanCloseAlertContext *canCloseAlertContext = inContextInfo;
void (*callback)(id, SEL, NSDocument *, BOOL, void* ) = (void (*)(id, SEL, NSDocument *, BOOL, void* ))objc_msgSend;
if (inAlertSheet) [inAlertSheet orderOut:self];
// The user's dismissed our "save changes?" alert sheet. What happens next depends on how the dismissal was done.
if (inReturnCode==NSAlertAlternateReturn)
{
//Cancel - do nothing.
}
else if (inReturnCode==NSAlertDefaultReturn)
{
//Yes - save the current document
[self saveDocumentWithDelegate:(__bridge id)canCloseAlertContext->delegate
didSaveSelector:canCloseAlertContext->shouldCloseSelector contextInfo:canCloseAlertContext->contextInfo];
}
else
{
// No - just clear the dirty flag and post a message to
// re-call the shouldCloseSelector. This should be
// the app:terminate routine.
[self clearDirtyFlag];
if (canCloseAlertContext->shouldCloseSelector)
{
(callback)((__bridge id)canCloseAlertContext->delegate,
canCloseAlertContext->shouldCloseSelector, self, YES, canCloseAlertContext->contextInfo);
}
}
// Free up the memory that was allocated in -canCloseDocumentWithDelegate:shouldCloseSelector:contextInfo:.
free(canCloseAlertContext);
}
#end
And that should do it - No loops... no waiting...
Does anyone know of any class or lib that can implement autocompletion to an NSTextField?
I'am trying to get the standard autocmpletion to work but it is made as a synchronous api. I get my autocompletion words via an api call over the internet.
What have i done so far is:
- (void)controlTextDidChange:(NSNotification *)obj
{
if([obj object] == self.searchField)
{
[self.spinner startAnimation:nil];
[self.wordcompletionStore completeString:self.searchField.stringValue];
if(self.doingAutocomplete)
return;
else
{
self.doingAutocomplete = YES;
[[[obj userInfo] objectForKey:#"NSFieldEditor"] complete:nil];
}
}
}
When my store is done, i have a delegate that gets called:
- (void) completionStore:(WordcompletionStore *)store didFinishWithWords:(NSArray *)arrayOfWords
{
[self.spinner stopAnimation:nil];
self.completions = arrayOfWords;
self.doingAutocomplete = NO;
}
The code that returns the completion list to the nstextfield is:
- (NSArray *)control:(NSControl *)control textView:(NSTextView *)textView completions:(NSArray *)words forPartialWordRange:(NSRange)charRange indexOfSelectedItem:(NSInteger *)index
{
*index = -1;
return self.completions;
}
My problem is that this will always be 1 request behind and the completion list only shows on every 2nd char the user inputs.
I have tried searching google and SO like a mad man but i cant seem to find any solutions..
Any help is much appreciated.
Instead of having the boolean property doingAutocomplete, make the property your control that made the request. Let's call it autoCompleteRequestor:
#property (strong) NSControl* autoCompleteRequestor;
So where you set your current property doingAutocomplete to YES, instead store a reference to your control.
- (void)controlTextDidChange:(NSNotification *)obj
{
if([obj object] == self.searchField)
{
[self.spinner startAnimation:nil];
[self.wordcompletionStore completeString:self.searchField.stringValue];
if(self.autoCompleteRequestor)
return;
else
{
self.autoCompleteRequestor = [[obj userInfo] objectForKey:#"NSFieldEditor"];
}
}
}
Now when your web request is done, you can call complete: on your stored object.
- (void) completionStore:(WordcompletionStore *)store didFinishWithWords:(NSArray *)arrayOfWords
{
[self.spinner stopAnimation:nil];
self.completions = arrayOfWords;
if (self.autoCompleteRequestor)
{
[self.autoCompleteRequestor complete:nil];
self.autoCompleteRequestor = nil;
}
}
NSTextView has the functionality of completing words of partial words.
Take a look at the documentation for this component.
Maybe you can switch to this component in your application.
Having a heck of a time with this one.
I've got a super-simple Cocoa app containing one WebView, a WebScripting API defined in the page, and a single NSObject defined on that API. When I turn on the debugger tools (in the embedded WebView), I can see the API on the JavaScript window object, and I can see my "api" property defined on that -- but when I call the API's "get" method, the arguments aren't being serialized -- when the Obj-C method gets called, the arguments are missing. See below, which hopefully illustrates:
I've combed through the docs, I've (apparently) set the appropriate methods to expose everything that needs to be exposed, and I can see the method being called. There has to be something stupid I'm missing, but as a relative newbie to this environment, I'm not seeing it.
Thanks in advance for your help!
Have you set WebKitDeveloperExtras to YES in your default user defaults when you send -[NSUserDefaults registerDefaults:]?
Depending on what version of Xcode you're using you could be getting a known error. If you're using LLDB on anything but the most recent version, it might not be giving you the right variables in the debugger. The solution has been to use GDB instead of LLDB until Apple fixes the problem. But I think they fixed the problem in the latest version. I'd change the debugger to use GDB and see if you're getting the right variables in Xcode. (Product-> Edit Scheme...-> Run -> Debugger). I came across this problem in iOS, though, so I don't know its applicability to OSX. Worth a try anyway.
I originally came across the problem here: https://stackoverflow.com/a/9485349/1147934
I process javascript in the main thread of my app from a local file stored in the apps directory. I check for beginning and ending tokens for the js functions I am executing and whether the function contains a variable.
Hopefully this can give you some good ideas for your issue. You could also do alerts in the js to see if the values post correctly as you run the app (I am sure you thought of that already, but it's worth mentioning.) Happy coding! I hope this helps!
in the .h file define:
NSMutableString *processedCommand;
NSArray *commandArguments;
In the .m file:
// tokens
#define kOpenToken #"<%%"
#define kCloseToken #"%%>"
// this will throw
-(void)executeJScriptCommand:(NSString *)aCommand {
[self performSelectorOnMainThread:#selector(executeThisCommand:) withObject:aCommand waitUntilDone:YES];
}
// this will throw
-(NSString *)executeCommand:(NSString *)command {
NSString *aCommand = [[[command stringByReplacingOccurrencesOfString:kOpenToken withString:#""]
stringByReplacingOccurrencesOfString:kCloseToken withString:#""]
stringByTrimmingLeadingAndTrailingWhitespaces];
if ([aCommand hasPrefix:#"="])
{
// variable. get value
[self getVariableFromCommand:aCommand];
}
else {
[self executeThisCommand:aCommand];
}
NSString *returnValue = [NSString stringWithString:processedCommand];
self.processedCommand = nil;
self.commandArguments = nil;
return returnValue;
}
-(void)executeThisCommand:(NSString *)aCommand {
BOOL hasError = NO;
// clear result
self.processedCommand = nil;
self.commandArguments = nil;
BOOL isFromJS = NO;
NSString *function = nil;
NSMutableArray *commandParts = nil;
#try {
// first, break the command into its parts and extract the function that needs to be called, and the (optional) arguments
commandParts = [[NSMutableArray alloc] initWithArray:[aCommand componentsSeparatedByString:#":"]];
if ([[[commandParts objectAtIndex:0] lowercaseString] isEqualToString:#"js-call"]) {
isFromJS = YES;
[commandParts removeObjectAtIndex:0];
}
// get our function, arguments
function = [[commandParts objectAtIndex:0] retain];
[commandParts removeObjectAtIndex:0];
if ([commandParts count] > 0){
if (isFromJS == YES) {
NSString *arguments = [[commandParts objectAtIndex:0] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
if ([arguments length] > 0) {
self.commandArguments = [arguments JSONValue];
}
}
else {
self.commandArguments = [NSArray arrayWithArray:commandParts];
}
}
// build invoke
SEL sel = NSSelectorFromString(function);
if ([self respondsToSelector:sel]) {
[self performSelectorOnMainThread:sel withObject:nil waitUntilDone:YES];
// using invocation causes a SIGABORT because the try/catch block was not catching the exception.
// using perform selector fixed the problem (i.e., the try/catch block now correctly catches the exception, as expected)
}
else {
[appDelegate buildNewExceptionWithName:#"" andMessage:[NSString stringWithFormat:#"Object does not respond to selector %#", function]];
}
}
#catch (NSException * e) {
hasError = YES;
[self updateErrorMessage:[NSString stringWithFormat:#"Error processing command %#: %#", aCommand, [e reason]]];
}
#finally {
[function release];
[commandParts release];
}
if (hasError == YES) {
[appDelegate buildNewExceptionWithName:#"executeThisCommand" andMessage:self.errorMessage];
}
}
// this can return nil
-(NSString *)getQueryStringValue:(NSString *)name {
NSString *returnValue = nil;
if (queryString != nil) {
returnValue = [queryString objectForKey:[name lowercaseString]];
}
return returnValue;
}
I'm trying to create the effect of an NSComboBox with completes == YES, no button, and numberOfVisibleItems == 0 (for an example, try filling in an Album or Artist in iTunes's Get Info window).
To accomplish this, I'm using an NSTextField control, which autocompletes on -controlTextDidChange: to call -[NSTextField complete:], which triggers the delegate method:
- (NSArray *)control:(NSControl *)control
textView:(NSTextView *)textView
completions:(NSArray *)words
forPartialWordRange:(NSRange)charRange
indexOfSelectedItem:(NSInteger *)index;
I've gotten this working correctly, the only problem being the side effect of a dropdown showing. I would like to suppress it, but I haven't seen a way to do this. I've scoured the documentation, Internet, and Stack Overflow, with no success.
I'd prefer a delegate method, but I'm open to subclassing, if that's the only way. I'm targeting Lion, in case it helps, so solutions don't need to be backward compatible.
To solve this, I had to think outside the box a little. Instead of using the built-in autocomplete mechanism, I built my own. This wasn't as tough as I had originally assumed it would be. My -controlTextDidChange: looks like so:
- (void)controlTextDidChange:(NSNotification *)note {
// Without using the isAutoCompleting flag, a loop would result, and the
// behavior gets unpredictable
if (!isAutoCompleting) {
isAutoCompleting = YES;
// Don't complete on a delete
if (userDeleted) {
userDeleted = NO;
} else {
NSTextField *control = [note object];
NSString *fieldName = [self fieldNameForTag:[control tag]];
NSTextView *textView = [[note userInfo] objectForKey:#"NSFieldEditor"];
NSString *typedText = [[textView.string copy] autorelease];
NSArray *completions = [self comboBoxValuesForField:fieldName
andPrefix:typedText];
if (completions.count >= 1) {
NSString *completion = [completions objectAtIndex:0];
NSRange difference = NSMakeRange(
typedText.length,
completion.length - typedText.length);
textView.string = completion;
[textView setSelectedRange:difference
affinity:NSSelectionAffinityUpstream
stillSelecting:NO];
}
}
isAutoCompleting = NO;
}
}
And then I implemented another delegate method I wasn't previously aware of (the missing piece of the puzzle, so to speak).
- (BOOL)control:(NSControl *)control
textView:(NSTextView *)textView doCommandBySelector:(SEL)commandSelector {
// Detect if the user deleted text
if (commandSelector == #selector(deleteBackward:)
|| commandSelector == #selector(deleteForward:)) {
userDeleted = YES;
}
return NO;
}
Update: Simplified and corrected solution
It now doesn't track the last string the user entered, instead detecting when the user deleted. This solves the problem in a direct, rather than roundabout, manner.