I am trying to learn how to create a CGEvent tap using examples on SO and and elsewhere.
I know how to create an event tap using:
let eventTap = CGEvent.tapCreate(*/arguments to create the tap*/)
After that I run
let runLoopSource = CFMachPortCreateRunLoopSource(kCFAllocatorDefault, eventTap, 0)
CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource, .commonModes)
Some, but not all examples I've found online also add the following two lines
CGEvent.tapEnable(tap: eventTap, enable: true)
CFRunLoopRun()
Can someone briefly explain if or when is adding the last two lines are useful/recommended?
The first is easy: the docs say:
Event taps are normally enabled when created. If an event tap becomes unresponsive, or if a user requests that event taps be disabled, then a kCGEventTapDisabled event is passed to the event tap callback function. Event taps may be re-enabled by calling this function.
The second one is probably for cases where the program doesn't have a run loop (on the current thread). For example, a command-line program which doesn't use NSApplication would need to create and run its own run loop.
Related
I have monster named Fungant in my 2D platform game.
It can hide as mushroom and rise to his normal form.
I try to handle it in code, but I don't know how to get information about finished animation (without it, animation of rising and hiding always was skipped).
I think the point there is to get info about complete of the one of two animations - Rise and Hide.
There is current code:
if (
fungantAnimator.GetCurrentAnimatorStateInfo(0).IsName("Fungant Rise")
)
{
fungantAnimator.SetBool("isRising", false);
isRisen = true;
fungantRigidbody.velocity = new Vector2(
walkSpeed * Mathf.Sign(
player.transform.position.x - transform.position.x),
fungantRigidbody.velocity.y
);
}
if (fungantAnimator.GetCurrentAnimatorStateInfo(0).IsName("Fungant Hide"))
{
fungantAnimator.SetBool("isHiding", false);
isRisen = false;
}
I try this two ways:
StateMachineBehaviour
I would like to get StateMachineBehaviour, but how to get it?
No idea how to process this further.
AnimationEvents
Tried to do with animation event but every tutorial have list of functions to choose (looks easy), but in my Unity I can write Function, Float, Int, String or select object (what I should do?).
I decided to write test() function with Debug only inside, and create AnimationEvents with written "test()" in function field, but nothing happens.
Same as above, no more ideas how to process this further.
I personally would use animation events for this. Just add an event to the animation and then the event plays a function after the animation transition is finished.
For more information on how to use animation events you can click here.
This post may also help you to add an event when the animation is finished.
I hope this answer helps you to solve this problem.
I want to check if a pdf file is changed or not, and if is changed i want to update the corresponding view. I don't know if it's more suitable to use a background process as a Thread or as an NSOperation to do this task. The Apple Documentation says: "Examples of tasks that lend themselves well to NSOperation include network requests, image resizing, text processing, or any other repeatable, structured, long-running task that produces associated state or data.But simply wrapping computation into an object doesn’t do much without a little oversight".
Also, if I understood correctly from the documentation, a Thread once started can't be stopped during his execution while an NSOperation could be paused or stopped and also they could rely on dependency to wait the completion of another task.
The workflow of this task should be more or less this diagram:
Task workflow
I managed to get the handler working after the notification of type .write has been sent. If i monitor for example a *.txt file everything works as expected and i receive only one notification. But i am monitoring a pdf file which is generated from terminal by pdflatex and thus i receive with '.write' nearly 15 notification. If i change to '.attrib' i get 3 notification. I need the handler to be called only once, not 15 or 3 times. Do you have any idea how can i do it or is not possible with a Dispatch Source? Maybe there is a way to execute a dispatchWorkItem only once?
I have tried to implement it like this(This is inside a FileMonitor class):
func startMonitoring()
{
....
let fileSystemRepresentation = fileManager.fileSystemRepresentation(withPath: fileStringURL)
let fileDescriptor = open(fileSystemRepresentation, O_EVTONLY)
let newfileMonitorSource = DispatchSource.makeFileSystemObjectSource(fileDescriptor: fileDescriptor,
eventMask: .attrib,
queue: queue)
newfileMonitorSource.setEventHandler(handler:
{
self.queue.async
{
print(" \n received first write event, removing handler..." )
self.newfileMonitorSource.setEventHandler(handler: nil)
self.test()
}
})
self.fileMonitorSource = newfileMonitorSource
fileMonitorSource!.resume()
}
func test()
{
fileMonitorSource?.cancel()
print(" restart monitoring ")
startMonitoring()
}
I have tried to reassign the handler in test(), but it's not working(if a regenerate the pdf file, what is inside the new handler it's not executed) and to me, doing in this way, it seems a bit boilerplate code. I have also tried the following things:
suspend the DispatchSource in the setEventHandler of startMonitoring() (passing nil), but then when i am resuming it, i get the remaining .write events.
cancel the DispatchSource object and recall the startMonitoring() as you can see in the code above, but in this way i create and destroy the DispatchSource object everytime i receive an event, which i don't like because the cancel() function shoul be called in my case only when the user decide to disable this feauture i am implementing.
I will try to write better how the workflow of the app should be so you can have an more clear idea of what i am doing:
When the app starts, a functions sets the default value of some checkboxes of the window preference. The user can modify this checkboxes. So when the user open a pdf file, the idea is to launch in a background thread the following task:
I create a new queue call it A and launch asynch an infinite while where i check the value of the UserDefault checkboxe (that i use to reload and update the pdf file) and two things could happen
if the user set the value to off and the pdf document has been loaded there could be two situations:
if there is no current monitoring of the file (when the app starts): continue to check the checkboxe value
if there is currently a monitoring of the file: stop it
if the user set value to on and the pdf document has been loaded in this background thread (the same queue A) i will create a class Monitor (that could be a subclass of NSThread or a class that uses DispatchSourceFileSystemObject like above), then i will call startMonitoring() that will check the date or .write events and when there is a change it will call the handler. Basically this handler should recall the main thread (the main queue) and check if the file can be loaded or is corrupted and if so update the view.
Note: The infinite while loop(that should be running in the background), that check the UserDefault related to the feature i am implementing it's launched when the user open the pdf file.
Because of the problem above (multiple handlers calls), i should use the cancel() function when the user set checkboxe to off, and not create/destroy the DispatchSource object everytime i receive a .write event.
I have an idle player animation and I want to do a smooth transition between some animations. The idle animation is the default one and from that transition I want to be able to switch to another state(let's say fight) and then back to idle. The code for the idle character animation is currently like :
self.addChild(playerAnimation)
playerAnimation.runAction(SKAction.repeatActionForever(
SKAction.animateWithTextures(playerAnimationManager.idleManAnimation.textureArray, timePerFrame: 0.1)))
Now, this is scheduled to go on forever for now, but I would need to intercept it and add a new animation on top of that (which is the same character, in a new state). I was thinking that I should stop the idle animation, switch to the new one and then back to idle when finished but I am not convinced that this is the best way of chaining animations and I haven't really found a good resource explaining how to go about it.
Any suggestions ? Thanks !
Depending on how short your texture array is, you might be able to do this.
I will try to explain without code seeing how I use objective C and you use Swift
First make a property or variable that can be called by any subroutine in this class file. It should be Boolean and should be set to NO. You could call it idleFlag.
Next make a method that changes the animation to fight mode. This change would be by removing the idle animation and replacing it with the fight animation. This method also set's idleFlag to NO. Let's call the method "beginFightAnim"
And last, in your repeatActionForEver idle animation, right after your animateWithTextures animation, add a runBlock animation. In this block define a static variable (one that will be remembered in the calling of the block over and over) and increment it by +1, add an "if statement" that looks something like this -> if (my_static_var == number_of_frames_in_texture_animations && idleFlag). And in the "if statement" set the static variable to 0 and call "beginFightAnim"
After this all you have to do to change the animation is set idleFlag to YES.
Hope it works!
If you have any problems, please comment below.
I want to do a series of examples to make it easier to understand the matter. Suppose you have your node called playerAnimation, a typical atlasc with a plist where you have
player-idle1.png
player-idle2.png
player-idle3.png
...
If you want to intercept in real-time your animation to know what frame is running in that moment you can do:
override func update(currentTime: CFTimeInterval) {
if String(playerAnimation.texture).rangeOfString("player-idle") != nil {
print(String(playerAnimation.texture))
}
}
At this point, after you have assigned a "key" to your action (withKey:"idleAnimation") you could stop your specific idle action when you preefer to start the other next animation.
Another good thing is to build a structure to know everytime your player status and modify this variable each time you launch a new action or animation:
enum PlayerStatus: Int {
case Idle = 1
case Fight = 2
case Run = 3
case Jump = 4
case Die = 5
...
}
var currentStatus: PlayerStatus!
This is all purely for educational purposes, to help me get a better understanding of how Parse as well as Swift operates.
I would like to make it so a user is only able to like an item once (not being able to hit a button multiple times), as currently, I'm utilizing an anonymous system with Parse.
Would I essentially use an if method with PFUser.CurrentUser() in the likeButton method to halt a user from hitting like again or would I use NSUserDefaults?
I'm not able to post code currently as I'm not near my laptop, however I could later if it helps. Still curious if I could get some info before that however.
Sample code I found on here from a previous question, which essentially implements the same idea.
#IBAction func likeButton(sender: AnyObject) {
let hitPoint = sender.convertPoint(CGPointZero, toView: self.tableView)
let hitIndex = self.tableView.indexPathForRowAtPoint(hitPoint)
let object = objectAtIndexPath(hitIndex)
object.incrementKey("count")
object.saveInBackground()
self.tableView.reloadData()
}
Would I call NSUsersDefaults to stunt the user from hitting it more than once?
Instead of calling saveInBackground(), you'd better call the method saveInBackgroundWithBlock: instead. So the strategy is very simple:
First of all, define a 'busy' flag for the object (For example: savingInBackground) and store it wherever you like ( If you are showing 1 item then simply declare a Bool property / If you are showing a list of Item then declare a Dictionary with format ["objectID/Index": Bool]). This flag should be set to true for the item being saved in the background.
Whenever use taps on a Like button
If current item's savingInBackground flag is true, then do nothing
Else:
Set item's savingInBackground to true
Increase Like count and Call saveInBackgroundWithBlock:
In the completion block of saveInBackgroundWithBlock:, set savingInBackground back to false.
I am on train now so I can't write example code, but I hope that it's clear enough to help you to achieve what you want.
I'm using Python 3.3 with Pygame and PygButton (low rep don't allow me more than two links)
My files at the moment are [int.py http://pastebin.com/sDRhieCG ] and [scene.py http://pastebin.com/Y2Mgsgmr ].
The idea is making a mainloop in int.py the smaller as possible. The code has a commented-out example of the start_screen buttons at the mainloop. It works, but with every new screen the mainloop would be bloated.
So I created a Scene class to apply background, texts and buttons. It works, but I can make the buttons work. E.g. the bquit button doesn't quit the screen (as it did previously when inserted into the mainloop).
I'm trying to create a scene_loop() inside the Scene() to run everything the specific scene has to offer. With a button click it would change scene and such, start a new scene_loop.
I can't seem to add specific methods after the Scene class is instanced, so I created a Scene_Start class to deal with specific methods like the scene_loop and its buttons (since the background is easily placed through the Scene class).
I'm just stuck and can't see a way to resolve this without scrapping everything and starting again.
Help?
tl;dr:
1. PygButton isn't working outside mainloop
2. How can I create a scene_loop that replaces the mainloop for that scene, "unbloating" mainloop (it would only take care of starting the app and changing scenes).
Thank You.
Problem solved. Answering my own question so it can be helpful to others.
Each class have a sceneloop method that runs and "replace" the mainloop. This allows for unbloating and isolating any problem into the scene without affecting the other components.
The mainloop:
while True:
for event in pg.event.get():
if event.type == QUIT or (event.type == KEYDOWN and event.key == K_ESCAPE):
pg.quit()
sys.exit()
scene.startscreen.draw()
scene.startscreen.sceneloop()
pg.display.update()
A sceneloop example. This is a method inside the Scene_Start(Scene) class, instanced as startscreen as show above in the main loop.
def sceneloop(self):
while self.scene_loop == True:
for event in pg.event.get():
if event.type == QUIT or (event.type == KEYDOWN and event.key == K_ESCAPE):
pg.quit()
sys.exit()
if 'click' in self.bcreate.handleEvent(event): #CREATE
startcreate.draw()
startcreate.sceneloop()
if 'click' in self.bstart.handleEvent(event): #START
pg.quit()
sys.exit()
if 'click' in self.bload.handleEvent(event): #LOAD
startload.draw()
startload.sceneloop()
if 'click' in self.boptions.handleEvent(event): #OPTIONS
startoptions.draw()
startoptions.sceneloop()
if 'click' in self.bquit.handleEvent(event): #QUIT
pg.quit()
sys.exit()
self.update()