Inject keyboard event into NSRunningApplication immediately after foregrounding it - macos

I am trying to bring to foreground a NSRunningApplication* instance, and inject a keyboard event.
NSRunningApplication* app = ...;
[app activateWithOptions: 0];
inject_keystrokes();
... fails to inject keyboard events, but:
NSRunningApplication* app = ...;
[app activateWithOptions: 0];
dispatch_time_t _100ms = dispatch_time( DISPATCH_TIME_NOW, (int64_t)(0.1 * NSEC_PER_SEC) );
dispatch_after(
_100ms,
dispatch_get_main_queue(),
^{ inject_keystrokes(); }
);
... succeeds.
I imagine it takes a certain amount of time for the window to render in the foreground, and maybe this happens on a separate thread, and this explains the injection failure.
However this is a very ugly solution. It relies on an arbitrary time interval.
It would be much cleaner to somehow wait for the window to complete foregrounding.
Is there any way of doing this?
PS inject_keystrokes() uses CGEventPost(kCGHIDEventTap, someCGEvent)
PPS Refs:
- Virtual keypress goes to wrong application
- Send NSEvent to background app
- http://advinprog.blogspot.com/2008/06/so-you-want-to-post-keyboard-event-in.html

Adding an observer for the KVO property isActive on NSRunningApplication works for me.
for (NSRunningApplication* ra in [[NSWorkspace sharedWorkspace] runningApplications])
{
if ([ra.bundleIdentifier isEqualToString:#"com.apple.TextEdit"])
{
[ra addObserver:self forKeyPath:#"isActive" options:0 context:ra];
[ra retain];
[ra activateWithOptions:0];
}
}
// ...
- (void)observeValueForKeyPath:(NSString*)keyPath ofObject:(id)object change:(NSDictionary*)change context:(void*)context
{
if ([keyPath isEqualToString:#"isActive"])
{
NSRunningApplication* ra = (NSRunningApplication*) context;
[ra removeObserver:self forKeyPath:#"isActive"];
[ra release];
inject_keystrokes();
}
}
Note that I manually retain and then release the NSRunningApplication to keep its reference alive, since I'm not keeping it in a property or ivar. You have to be careful that the reference doesn't get dropped with the observer still attached.

Related

objective c WatchKit WKInterfaceController openParentApplication call blocks indefinitely

I'm using the following code to "simply" determine the application state of the parent application from my watch app:
WatchKit Extension:
[WKInterfaceController openParentApplication:[NSDictionary dictionary] reply:^(NSDictionary *replyInfo, NSError *error)
{
UIApplicationState appState = UIApplicationStateBackground;
if(nil != replyInfo)
appState = (UIApplicationState)[((NSNumber*)[replyInfo objectForKey:kAppStateKey]) integerValue];
//handle app state
}];
Main App:
- (void)application:(UIApplication *)application handleWatchKitExtensionRequest:(NSDictionary *)userInfo reply:(void (^)(NSDictionary *replyInfo))reply
{
__block UIBackgroundTaskIdentifier realBackgroundTask;
realBackgroundTask = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
reply([NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:[[UIApplication sharedApplication] applicationState]], kAppStateKey, nil]);
[[UIApplication sharedApplication] endBackgroundTask:realBackgroundTask];
}];
reply([NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:[[UIApplication sharedApplication] applicationState]], kAppStateKey, nil]);
[[UIApplication sharedApplication] endBackgroundTask:realBackgroundTask];
}
When the app is in the foreground this works 100% of the time. When the app is "minimized" or "terminated" this maybe works 50% of the time (maybe less). When it doesn't work it appears to be blocking indefinitely. If after 1 minute, for example, I launch the parent app, the call (openParentApplication) immediately returns with the state "UIApplicationStateBackground" (the state it was before I launched the app as clearly the app isn't in the background state if I launched it).
BTW: I'm testing with real hardware.
What am I doing wrong? Why is iOS putting my main app to sleep immediately after receiving the call even though I create a background task? This is a complete show-stopper.
Any thoughts or suggestions would be greatly appreciated!!
After some research it looks to be a known issue. For example, the following link identifies this issue and provides a solution:
http://www.fiveminutewatchkit.com/blog/2015/3/11/one-weird-trick-to-fix-openparentapplicationreply
However, this solution did not work for me. As a result I implemented the following solution (its a little sloppy, but this is intentional to help condense the solution):
//start the timeout timer
timeoutTimer = [NSTimer scheduledTimerWithTimeInterval:kTimeOutTime target:self selector:#selector(onTimeout) userInfo:nil repeats:NO];
//make the call
messageSent = [WKInterfaceController openParentApplication:[NSDictionary dictionary] reply:^(NSDictionary *replyInfo, NSError *error)
{
if(nil != _stateDelegate)
{
UIApplicationState appState = UIApplicationStateBackground;
if(nil != replyInfo)
appState = (UIApplicationState)[((NSNumber*)[replyInfo objectForKey:kAppStateKey]) integerValue];
[_stateDelegate onOperationComplete:self timeout:false applicationState:appState];
_stateDelegate = nil;
}
}];
//if the message wasn't sent, then this ends now
if(!messageSent)
{
if(nil != _stateDelegate)
{
//just report that the main application is inactive
[_stateDelegate onOperationComplete:self timeout:false applicationState:UIApplicationStateInactive];
}
_stateDelegate = nil;
}
-(void)onTimeout
{
timeoutTimer = nil;
if(nil != _stateDelegate)
{
[_stateDelegate onOperationComplete:self timeout:true applicationState:UIApplicationStateInactive];
}
_stateDelegate = nil;
}
In a nutshell, if the timer fires before I hear back from the main app I will basically assume that the main app has been put to sleep. Keep in mind that all pending calls will succeed at some point (e.g. app state is restored to active) and, thus, you will need to handle this scenario (if necessary).

Cocoa/OSX - Strange behavior in NSSavePanel that not shows sub-itens

I've a NSSavePanel instance with a strange behavior: whenever I open it and click on a directory's arrow (the little expand button) it shows an indeterminate loading icon on the left-bottom corner that never ends, and not shows the directory/file tree. An image can see as follow:
In that example, I've clicked in "workspace" directory. And the panel not shows the sub-itens. Even strange is that after I click it again (redrawing the directory) and then click again (re-open the directory), it properly shows all files.
My code is as follows:
// here, I'm creating a web service client, and then calling a method to download a report, and passing the same class as delegate
- (IBAction) generateReport:(id)sender {
// SOME STUFF HERE...
WSClient *client = [[[WSClient alloc] init] initWithDelegate:self];
[client GenerateReport:#"REPORT" withParams:params];
}
- (void) GenerateReport:(NSString *)from withParams:(NSDictionary *)parameters {
// SOME STUFF HERE...
NSOperationQueue *queue = [[NSOperationQueue alloc] init];
[NSURLConnection sendAsynchronousRequest:request queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
if (!error) {
dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void) {
dispatch_async(dispatch_get_main_queue(), ^(void) {
NSLog(#"GenerateReport: [success]");
[self.delegate successHandlerCallback:data from: from];
});
});
}
}];
// this is the callback
- (void) successHandlerCallback:(NSData *) data from: (NSString *) from {
NSString savePath = [savePath stringByReplacingOccurrencesOfString:#"file://" withString:#""];
NSString *filePath = [NSString stringWithFormat:#"%#", savePath];
[data writeToFile:filePath atomically:YES];
}
// and this is to build a panel to let user chose the directory to save the file
- (NSURL *) getDirectoryPath {
NSSavePanel *panel = [NSSavePanel savePanel];
[panel setNameFieldStringValue:[self getDefaultFileName]];
[panel setDirectoryURL:[NSURL fileURLWithPath:[[NSString alloc] initWithFormat:#"%#%#%#", #"/Users/", NSUserName(), #"/Downloads"]]];
if ([panel runModal] != NSFileHandlingPanelOKButton) return nil;
return [panel URL];
}
Can someone give a hint on where I'm missing?
UPDATE: To me, it seens to be something related with dispatch_async!
Thanks in advance!
Actually, this is a bad interaction between NSSavePanel and the Grand Central Dispatch main queue and/or +[NSOperationQueue mainQueue]. You can reproduce it with just this code:
dispatch_async(dispatch_get_main_queue(), ^{
[[NSSavePanel savePanel] runModal];
});
First, any time you perform GUI operations, you should do so on the main thread. (There are rare exceptions, but you should ignore them for now.) So, you were right to submit the work to the main queue if it was going to do something like open a file dialog.
Unfortunately, the main queue is a serial queue, meaning that it can only run one task at a time, and NSSavePanel submits some of its own work to the main queue. So, if you submit a task to the main queue and that task runs the save panel in a modal fashion, then it monopolizes the main queue until the save panel completes. But the save panel is relying on the ability to submit its own tasks to the main queue and have them run.
As far as I'm concerned, this is a bug in Cocoa. You should submit a bug report to Apple.
The correct solution is for NSSavePanel to submit any tasks it has to the main thread using a re-entrant mechanism like a run-loop source, -performSelectorOnMainThread:..., or CFRunLoopPerformBlock(). It needs to avoid using the main queue of GCD or NSOperationQueue.
Since you can't wait for Apple to fix this, the workaround is for you to do the same. Use one of the above mechanisms to submit your task that may run the save panel to the main queue.
I just found the way: I was making all the calls within the dispatch_async on the main thread queue. By the fact that the download is still running at the callback moment, it conflicted with the thread that opens the panel. I fixed all issues by just placing the correct lines, changing from:
dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void) {
dispatch_async(dispatch_get_main_queue(), ^(void) {
NSLog(#"GenerateReport: [success]");
[self.delegate successHandlerCallback:data from: from];
});
});
to:
dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void) {
NSLog(#"GenerateReport: [success]");
[self.delegate successHandlerCallback:data from: from];
});
and in the callback, just updating the fields. In the end, I found that all of that were a main/background thread misunderstand by me.

Cocoa: Displaying an error after NSApp beginSheet results the main window hiding

I have broken this down into a very small project. Using the following code in the application delegate:
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
TestingWindowController * testingWindowController = [[TestingWindowController alloc] initWithWindowNibName: #"TestingWindowController"];
// Begin our sheet
[NSApp beginSheet: testingWindowController.window
modalForWindow: self.window
modalDelegate: self
didEndSelector: #selector(windowDidEnd:returnCode:contextInfo:)
contextInfo: NULL];
}
- (void)windowDidEnd:(id)alert returnCode:(NSInteger)returnCode contextInfo:(id) contextInfo
{
// If the user did not accept, then we really don't care what else they did!
if (returnCode != NSOKButton) return;
// We have had an error. Display it.
[[NSApplication sharedApplication] presentError: nil
modalForWindow: self.window
delegate: nil
didPresentSelector: nil
contextInfo: NULL];
}
And the following action tied to button on the windows nib. (Note that the nib's window is also set to not be visible on launch).
- (IBAction) onClose: (id) sender
{
[[NSApplication sharedApplication] endSheet: self.window
returnCode: NSOKButton];
[self.window orderOut: nil];
} // End of onClose
What ends up happening is, once I the onClose runs, all of the windows disappear and I am left with nothing but the error dialog (the main window has disappeared).
Is there something wrong with my code? Why does my main window go away?
NOTE: I know that I am not passing an error to the presentError method. I purposely left this null as I only had a short time to write the sample code. Passing an actual error results in the same behaviour.
Sample project is available here.
Looks like you are still using the old api, try the new one
(deselect Always visible at launch for the UserLoginWindowController window)
- (IBAction)userButtonPressed:(id)sender {
UserLoginWindowController * wc = [UserLoginWindowController new];
// we keep a reference, so the WC doesn't deallocate
self.modalWindowController = wc;
[[self window] beginSheet:[wc window] completionHandler:^(NSModalResponse returnCode) {
self.modalWindowController = nil;
}];
}
in the UserLoginWindowController
- (IBAction)cancelButtonPressed:(id)sender {
[[[self window] sheetParent] endSheet:[self window] returnCode:NSModalResponseCancel];
}
You are using 2 methods to open your window, beginSheet:....., and runModalForWindow:. You only need one of those. If you want a sheet attached to your window, use the first method, if you want a stand alone window, use the second. Likewise, in your onClose method, you should use endSheet:returnCode: if you're closing a sheet (the argument for that method should be testingWindowController.window not self.window) , and stopModalWithCode: if you're closing a modal window, you shouldn't have both.

NSOutlineView not refreshing when objects added to managed object context from NSOperations

Background
Cocoa app using core data Two
processes - daemon and a main UI
Daemon constantly writing to a data store
UI process reads from same data
store
Columns in NSOutlineView in UI bound to
an NSTreeController
NSTreeControllers managedObjectContext is bound to
Application with key path of
delegate.interpretedMOC
NSTreeControllers entity is set to TrainingGroup (NSManagedObject subclass is called JGTrainingGroup)
What I want
When the UI is activated, the outline view should update with the latest data inserted by the daemon.
The Problem
Main Thread Approach
I fetch all the entities I'm interested in, then iterate over them, doing refreshObject:mergeChanges:YES. This works OK - the items get refreshed correctly. However, this is all running on the main thread, so the UI locks up for 10-20 seconds whilst it refreshes. Fine, so let's move these refreshes to NSOperations that run in the background instead.
NSOperation Multithreaded Approach
As soon as I move the refreshObject:mergeChanges: call into an NSOperation, the refresh no longer works. When I add logging messages, it's clear that the new objects are loaded in by the NSOperation subclass and refreshed. It seems that no matter what I do, the NSOutlineView won't refresh.
What I've tried
I've messed around with this for 2 days solid and tried everything I can think of.
Passing objectIDs to the NSOperation to refresh instead of an entity name.
Resetting the interpretedMOC at various points - after the data refresh and before the outline view reload.
I'd subclassed NSOutlineView. I discarded my subclass and set the view back to being an instance of NSOutlineView, just in case there was any funny goings on here.
Added a rearrangeObjects call to the NSTreeController before reloading the NSOutlineView data.
Made sure I had set the staleness interval to 0 on all managed object contexts I was using.
I've got a feeling this problem is somehow related to caching core data objects in memory. But I've totally exhausted all my ideas on how I get this to work.
I'd be eternally grateful to anyone who can shed any light as to why this might not be working.
Code
Main Thread Approach
// In App Delegate
-(void)applicationDidBecomeActive:(NSNotification *)notification {
// Delay to allow time for the daemon to save
[self performSelector:#selector(refreshTrainingEntriesAndGroups) withObject:nil afterDelay:3];
}
-(void)refreshTrainingEntriesAndGroups {
NSSet *allTrainingGroups = [[[NSApp delegate] interpretedMOC] fetchAllObjectsForEntityName:kTrainingGroup];
for(JGTrainingGroup *thisTrainingGroup in allTrainingGroups)
[interpretedMOC refreshObject:thisTrainingGroup mergeChanges:YES];
NSError *saveError = nil;
[interpretedMOC save:&saveError];
[windowController performSelectorOnMainThread:#selector(refreshTrainingView) withObject:nil waitUntilDone:YES];
}
// In window controller class
-(void)refreshTrainingView {
[trainingViewTreeController rearrangeObjects]; // Didn't really expect this to have any effect. And it didn't.
[trainingView reloadData];
}
NSOperation Multithreaded Approach
// In App Delegate (just the changed method)
-(void)refreshTrainingEntriesAndGroups {
JGRefreshEntityOperation *trainingGroupRefresh = [[JGRefreshEntityOperation alloc] initWithEntityName:kTrainingGroup];
NSOperationQueue *refreshQueue = [[NSOperationQueue alloc] init];
[refreshQueue setMaxConcurrentOperationCount:1];
[refreshQueue addOperation:trainingGroupRefresh];
while ([[refreshQueue operations] count] > 0) {
[[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.05]];
// At this point if we do a fetch of all training groups, it's got the new objects included. But they don't show up in the outline view.
[windowController performSelectorOnMainThread:#selector(refreshTrainingView) withObject:nil waitUntilDone:YES];
}
// JGRefreshEntityOperation.m
#implementation JGRefreshEntityOperation
#synthesize started;
#synthesize executing;
#synthesize paused;
#synthesize finished;
-(void)main {
[self startOperation];
NSSet *allEntities = [imoc fetchAllObjectsForEntityName:entityName];
for(id thisEntity in allEntities)
[imoc refreshObject:thisEntity mergeChanges:YES];
[self finishOperation];
}
-(void)startOperation {
[self willChangeValueForKey:#"isExecuting"];
[self willChangeValueForKey:#"isStarted"];
[self setStarted:YES];
[self setExecuting:YES];
[self didChangeValueForKey:#"isExecuting"];
[self didChangeValueForKey:#"isStarted"];
imoc = [[NSManagedObjectContext alloc] init];
[imoc setStalenessInterval:0];
[imoc setUndoManager:nil];
[imoc setPersistentStoreCoordinator:[[NSApp delegate] interpretedPSC]];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(mergeChanges:)
name:NSManagedObjectContextDidSaveNotification
object:imoc];
}
-(void)finishOperation {
saveError = nil;
[imoc save:&saveError];
if (saveError) {
NSLog(#"Error saving. %#", saveError);
}
imoc = nil;
[self willChangeValueForKey:#"isExecuting"];
[self willChangeValueForKey:#"isFinished"];
[self setExecuting:NO];
[self setFinished:YES];
[self didChangeValueForKey:#"isExecuting"];
[self didChangeValueForKey:#"isFinished"];
}
-(void)mergeChanges:(NSNotification *)notification {
NSManagedObjectContext *mainContext = [[NSApp delegate] interpretedMOC];
[mainContext performSelectorOnMainThread:#selector(mergeChangesFromContextDidSaveNotification:)
withObject:notification
waitUntilDone:YES];
}
-(id)initWithEntityName:(NSString *)entityName_ {
[super init];
[self setStarted:false];
[self setExecuting:false];
[self setPaused:false];
[self setFinished:false];
[NSThread setThreadPriority:0.0];
entityName = entityName_;
return self;
}
#end
// JGRefreshEntityOperation.h
#interface JGRefreshEntityOperation : NSOperation {
NSString *entityName;
NSManagedObjectContext *imoc;
NSError *saveError;
BOOL started;
BOOL executing;
BOOL paused;
BOOL finished;
}
#property(readwrite, getter=isStarted) BOOL started;
#property(readwrite, getter=isPaused) BOOL paused;
#property(readwrite, getter=isExecuting) BOOL executing;
#property(readwrite, getter=isFinished) BOOL finished;
-(void)startOperation;
-(void)finishOperation;
-(id)initWithEntityName:(NSString *)entityName_;
-(void)mergeChanges:(NSNotification *)notification;
#end
UPDATE 1
I just found this question. I can't understand how I missed it before I posted mine, but the summary is: Core Data wasn't designed to do what I'm doing. Only one process should be using a data store.
NSManagedObjectContext and NSArrayController reset/refresh problem
However, in a different area of my application I have two processes sharing a data store with one having read only access and this seemed to work fine. Plus none of the answers to my last question on this topic mentioned that this wasn't supported in Core Data.
I'm going to re-architect my app so that only one process writes to the data store at any one time. I'm still skeptical that this will solve my problem though. It looks to me more like an NSOutlineView refreshing problem - the objects are created in the context, it's just the outline view doesn't pick them up.
I ended up re-architecting my app. I'm only importing items from one process or the other at once. And it works perfectly. Hurrah!

NSThread with _NSAutoreleaseNoPool error

I have an method which save files to the internet, it works but just slow. Then I'd like to make the user interface more smooth, so I create an NSThread to handle the slow task.
I am seeing a list of errors like:
_NSAutoreleaseNoPool(): Object 0x18a140 of class NSCFString autoreleased with no pool in place - just leaking
Without NSThread, I call the method like:
[self save:self.savedImg];
And I used the following to use NSThread to call the method:
NSThread* thread1 = [[NSThread alloc] initWithTarget:self
selector:#selector(save:)
object:self.savedImg];
[thread1 start];
Thanks.
Well first of all, you are both creating a new thread for your saving code and then using NSUrlConnection asynchronously. NSUrlConnection in its own implementation would also spin-off another thread and call you back on your newly created thread, which mostly is not something you are trying to do. I assume you are just trying to make sure that your UI does not block while you are saving...
NSUrlConnection also has synchronous version which will block on your thread and it would be better to use that if you want to launch your own thread for doing things. The signature is
+ sendSynchronousRequest:returningResponse:error:
Then when you get the response back, you can call back into your UI thread. Something like below should work:
- (void) beginSaving {
// This is your UI thread. Call this API from your UI.
// Below spins of another thread for the selector "save"
[NSThread detachNewThreadSelector:#selector(save:) toTarget:self withObject:nil];
}
- (void) save {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// ... calculate your post request...
// Initialize your NSUrlResponse and NSError
NSUrlConnection *conn = [NSUrlConnection sendSyncronousRequest:postRequest:&response error:&error];
// Above statement blocks until you get the response, but you are in another thread so you
// are not blocking UI.
// I am assuming you have a delegate with selector saveCommitted to be called back on the
// UI thread.
if ( [delegate_ respondsToSelector:#selector(saveCommitted)] ) {
// Make sure you are calling back your UI on the UI thread as below:
[delegate_ performSelectorOnMainThread:#selector(saveCommitted) withObject:nil waitUntilDone:NO];
}
[pool release];
}
You need to mainly create an autorelease pool for the thread. Try changing your save method to be like this:
- (void) save:(id)arg {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
//Existing code
[pool drain];
}
You will not you that the above does not call release on the NSAutoreleasePool. This is a special case. For NSAutoreleasePool drain is equivalent to release when running without GC, and converts to a hint to collector that it might be good point to run a collection.
You may need to create a run loop. I will add to Louis's solution:
BOOL done = NO;
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
[NSRunLoop currentRunLoop];
// Start the HTTP connection here. When it's completed,
// you could stop the run loop and then the thread will end.
do {
SInt32 result = CFRunLoopRunInMode(kCFRunLoopDefaultMode, 1, YES);
if ((result == kCFRunLoopRunStopped) || (result == kCFRunLoopRunFinished)) {
done = YES;
}
} while (!done);
[pool release];
Within the thread, you need to create a new autorelease pool before you do anything else, otherwise the network operations will have issues as you saw.
I don't see any reason for you to use threads for this. Simply doing it asynchronously on the run loop should work without blocking the UI.
Trust in the run loop. It's always easier than threading, and is designed to provide the same result (a never-blocked UI).

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