I am trying to automate some tasks (there's no applescript support) so I have to use CGEvents and post these events. Mouse clicking works fine, but NSKeyDown (enter) only works if I click on the app in the dock(which makes it front most app)...
Here's my code so far:
for (NSDictionary *dict in windowList) {
NSLog(#"%#", dict);
if ([[dict objectForKey:#"kCGWindowName"] isEqualToString:#"Some Window..."]) {
WIDK = [[dict objectForKey:#"kCGWindowNumber"] intValue];
break;
};
}
CGEventRef CGEvent;
NSEvent *customEvent;
customEvent = [NSEvent keyEventWithType:NSKeyDown
location:NSZeroPoint
modifierFlags:0
timestamp:1
windowNumber:WIDK
context:nil
characters:nil
charactersIgnoringModifiers:nil
isARepeat:NO
keyCode:36];
CGEvent = [customEvent CGEvent];
for (int i=0; i <5; i++) {
sleep(3);
CGEventPostToPSN(&psn, CGEvent);
NSLog(#"posted the event");
}
CFRelease(eOne);
The reason why I have posteventtopsn in a loop is for testing purposes (I just need it to send it once). While the program is in the loop, if I activate my app to front most, then the event works fine.
What am I doing wrong? Is there a way it can work if it in background? Thanks.
Here is a better way to post keyboard events to the front-most application:
CGEventRef a = CGEventCreateKeyboardEvent(NULL, 124, true);
CGEventRef b = CGEventCreateKeyboardEvent(NULL, 124, false);
CGEventPost(kCGHIDEventTap, a);
CGEventPost(kCGHIDEventTap, b);
CGEventPost lets you determine where the event is posted. I used this code recently to allow someone to remotely control a PPT presentation on my laptop. (Character 124 is the right arrow key.)
Note that you should be freeing the event after posting it.
You can send to a specific app (eg not the front app) by using CGEventPostToPSN.
i think it's because you create a NSEvent using "WIDK" for parameter windowNumber , and WIDK is related to your app only.
Related
I am writing an audio plugin (VST) in Objective-C on OSX. My plugin gets loaded into an application and is given an NSWindow in which to add my own NSView. I need to be able to intercept keyboard events on the NSWindow which I can partly do, but not fully.
Here's what I have tried so far:
Make sure my view is the first response and handle keyDown events. This works for most keyDown events, but not carriage return or special keys like cut/copy/paste.
Use addLocalMonitorForEventsMatchingMask. This doesn't provide anything more useful than keyDown.
The NSWindow I'm given has a menu with some key equivalents for cut/copy/paste. I occasionally need to intercept these if the user has something selected in my NSView. I also occasionally need to intercept carriage return if the user is entering some data.
My UI is rendered using OpenGL so I'm not using standard Cocoa UI components apart from NSView to host my OpenGL surface.
I don't want the user to have to enable anything special to do this, like accessibility.
In my keyDown handler I have something like this:
- (void)keyDown:(NSEvent*)event
{
NSString* s = event.charactersIgnoringModifiers;
unichar modified_key = 0;
if (s && [s length] > 0)
{
modified_key = [s characterAtIndex:0];
}
if (modified_key == NSCarriageReturnCharacter)
{
// carriage return
}
}
This works in a stand alone application, but fails when it's hosted as an audio plugin. The problem I think is that the application hosting the plugin is intercepting events before they reach my event handlers.
You seem to be handling the event in a strange way. Process the NSEvent keyCode directly. You can use modifierFlags to get the modifiers.
This won't work for certain "system" key combinations (like Command + Space) for which you will need accessibility access.
- (void)keyDown:(NSEvent *)event
{
if (event.keyCode == 36)
NSLog(#"you pressed return!");
if (event.modifierFlags & NSEventModifierFlagCommand)
{
if (event.keyCode == 8)
NSLog(#"you pressed command+c!");
}
}
You can list the currently open windows using CGWindowListCreate, e.g:
CFArrayRef windowListArray = CGWindowListCreate(kCGWindowListOptionOnScreenOnly|kCGWindowListExcludeDesktopElements, kCGNullWindowID);
NSArray *windows = CFBridgingRelease(CGWindowListCreateDescriptionFromArray(windowListArray));
// stuff here with windows array
CFRelease(windowListArray);
With this you can get a specific window, e.g. a window from Chrome that's somewhere in the background of the current workspace, but not minimized. I also found that you can simulate mouse-clicks anywhere on-screen using CGEventCreateMouseEvent:
CGEventRef click_down = CGEventCreateMouseEvent(NULL, kCGEventLeftMouseDown, point, kCGMouseButtonLeft);
CGEventPost(kCGHIDEventTap, click_down);
Instead of sending this event to the front-most window under this point on the screen, can I send this to a window in background? Or is the only way to temporarily switch to that window (bring it to front), click, and switch back to the previous frontmost window?
This post suggests the latter is possible:
Cocoa switch focus to application and then switch it back
Although I'm very interested in seeing whether this can be avoided, whether we can send mouse-clicks directly to a specific window in background without bringing it into view. I can consider any Objective-C, C, or C++ options for this.
Finally got this working after finding an alternative to the deprecated GetPSNForPID function:
NSEvent *customEvent = [NSEvent mouseEventWithType: NSEventTypeLeftMouseDown
location: point
modifierFlags: NSEventModifierFlagCommand
timestamp:[NSDate timeIntervalSinceReferenceDate]
windowNumber:[self.windowID intValue]
context: nil
eventNumber: 0
clickCount: 1
pressure: 0];
CGEvent = [customEvent CGEvent];
CGEventPostToPid(PID, CGEvent);
Didn't realise there was a CGEventPostToPid method instead of CGEventPostToPSN. No need for the ProcessSerialNumber struct.
In Mac OS ML one can setup to switch dictation on by pressing fn key twice. I would like to use the same global shortcut in my application. Does anyone have experience with watching for double pressed keys?
With NSEvent you can setup a global monitor using addGlobalMonitorForEventsMatchingMask:handler: Here is the bit of code that will allow you to monitor for the fn key but you can of course change it no anything if you also filter for NSKeyDownMask.
__block double prevTimeInterval = 0;
[NSEvent addGlobalMonitorForEventsMatchingMask:NSFlagsChangedMask handler:^(NSEvent *theEvent) {
if (theEvent.keyCode == 63) {
if (theEvent.timestamp - prevTimeInterval < 0.2)
NSLog(#"Double pressed fn key");
prevTimeInterval = theEvent.timestamp;
}
}];
I'm trying to learn to code for the Mac. I've been a Java guy for a while, so I hope the problem I'm running into is a simple misunderstanding of Cocoa.
I've got the following code:
-(IBAction)beginEventMonitor:(id)sender {
_eventMonitor = [NSEvent addGlobalMonitorForEventsMatchingMask:(NSLeftMouseUpMask)
handler:^(NSEvent *incomingEvent) {
//NSWindow *targetWindowForEvent = [incomingEvent window];
NSLog(#"Got a mouse click event at %#", NSStringFromPoint([incomingEvent locationInWindow]));
}];
}
-(IBAction)stopEventMonitor:(id)sender {
if (_eventMonitor) {
[NSEvent removeMonitor:_eventMonitor];
_eventMonitor = nil;
}
}
This is a simple hook to tell me when a mouse click happens at a global level. The handler is working, but the contents of the incomingEvent don't seem to be set to anything. The only useful information that I can find is the location of the mouse at the time of the click, and the windowId of the window that was clicked in.
Shouldn't I be able to get more information? Am I not setting up the monitor correctly? I'd really like to be able to know which window was clicked in, but I can't even find a way to turn the mouse location or windowId into something useful.
You can retrieve more information about the window using the CGWindow APIs (new in Leopard), for example:
CGWindowID windowID = (CGWindowID)[incomingEvent windowNumber];
CFArrayRef a = CFArrayCreate(NULL, (void *)&windowID, 1, NULL);
NSArray *windowInfos = (NSArray *)CGWindowListCreateDescriptionFromArray(a);
CFRelease(a);
if ([windowInfos count] > 0) {
NSDictionary *windowInfo = [windowInfos objectAtIndex:0];
NSLog(#"Name: %#", [windowInfo objectForKey:(NSString *)kCGWindowName]);
NSLog(#"Owner: %#", [windowInfo objectForKey:(NSString *)kCGWindowOwnerName]);
//etc.
}
[windowInfos release];
There's lots of information there (look in CGWindow.h or refer to the docs for available keys). There are also functions to create screenshots of just one window (which even works if it's partially covered by another window), cool stuff!
Using touchesBeganWithEvent, touchesEndedWithEvent, etc you can get the touch data from the multitouch trackpad, but is there a way to block that touch data from moving the mouse/activating the system-wide gestures (similar to what is done in the chinese text input)?
As noted by valexa, using NSEventMask for CGEventTap is a hack. Tarmes also notes that Rob Keniger's answer no longer works (OS X >= 10.8). Luckily, Apple has provided a way to do this quite easily by using kCGEventMaskForAllEvents and converting the CGEventRef to an NSEvent within the callback:
NSEventMask eventMask = NSEventMaskGesture|NSEventMaskMagnify|NSEventMaskSwipe|NSEventMaskRotate|NSEventMaskBeginGesture|NSEventMaskEndGesture;
CGEventRef eventTapCallback(CGEventTapProxy proxy, CGEventType type, CGEventRef eventRef, void *refcon) {
// convert the CGEventRef to an NSEvent
NSEvent *event = [NSEvent eventWithCGEvent:eventRef];
// filter out events which do not match the mask
if (!(eventMask & NSEventMaskFromType([event type]))) { return [event CGEvent]; }
// do stuff
NSLog(#"eventTapCallback: [event type] = %d", [event type]);
// return the CGEventRef
return [event CGEvent];
}
void initCGEventTap() {
CFMachPortRef eventTap = CGEventTapCreate(kCGSessionEventTap, kCGHeadInsertEventTap, kCGEventTapOptionListenOnly, kCGEventMaskForAllEvents, eventTapCallback, nil);
CFRunLoopAddSource(CFRunLoopGetCurrent(), CFMachPortCreateRunLoopSource(kCFAllocatorDefault, eventTap, 0), kCFRunLoopCommonModes);
CGEventTapEnable(eventTap, true);
CFRunLoopRun();
}
Note that the call to CFRunLoopRun() is included since this snippet was taken from a project which could not use NSApplication but instead had a bare-bones CFRunLoop. Omit it if you use NSApplication.
UPDATE: my answer below no longer works. See the answer here.
Usually to do this you'd need to use a Quartz Event Tap, although the touch events don't seem to be "officially" supported by the CGEvent API. The non-multitouch event types in NSEvent.h seem to map to the CGEvent types in CGEventTypes.h, so the multitouch ones will probably work, even if they're not documented.
In order to block the events from propagating, you need to return NULL from the event tap callback.
You'd need some code like this:
#import <ApplicationServices/ApplicationServices.h>
//assume CGEventTap eventTap is an ivar or other global
void createEventTap(void)
{
CFRunLoopSourceRef runLoopSource;
//listen for touch events
//this is officially unsupported/undocumented
//but the NSEvent masks seem to map to the CGEvent types
//for all other events, so it should work.
CGEventMask eventMask = (
NSEventMaskGesture |
NSEventMaskMagnify |
NSEventMaskSwipe |
NSEventMaskRotate |
NSEventMaskBeginGesture |
NSEventMaskEndGesture
);
// Keyboard event taps need Universal Access enabled,
// I'm not sure about multi-touch. If necessary, this code needs to
// be here to check whether we're allowed to attach an event tap
if (!AXAPIEnabled()&&!AXIsProcessTrusted()) {
// error dialog here
NSAlert *alert = [[[NSAlert alloc] init] autorelease];
[alert addButtonWithTitle:#"OK"];
[alert setMessageText:#"Could not start event monitoring."];
[alert setInformativeText:#"Please enable \"access for assistive devices\" in the Universal Access pane of System Preferences."];
[alert runModal];
return;
}
//create the event tap
eventTap = CGEventTapCreate(kCGHIDEventTap, //this intercepts events at the lowest level, where they enter the window server
kCGHeadInsertEventTap,
kCGEventTapOptionDefault,
eventMask,
myCGEventCallback, //this is the callback that we receive when the event fires
nil);
// Create a run loop source.
runLoopSource = CFMachPortCreateRunLoopSource(kCFAllocatorDefault, eventTap, 0);
// Add to the current run loop.
CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource, kCFRunLoopCommonModes);
// Enable the event tap.
CGEventTapEnable(eventTap, true);
}
//the CGEvent callback that does the heavy lifting
CGEventRef myCGEventCallback(CGEventTapProxy proxy, CGEventType type, CGEventRef theEvent, void *refcon)
{
//handle the event here
//if you want to capture the event and prevent it propagating as normal, return NULL.
//if you want to let the event process as normal, return theEvent.
return theEvent;
}