Invalidating a nstimer
One of the events that is checked for is the ‘timer interval elapsed event’.
When the run loop detects this kind of event it will fire the method on the target associated with the timer. The reason: there is a point in the loop () in which the timer events are managed.
From the article, creating a scheduled, non-repeating timer can be done something like this: This will create a timer that is fired after 2.0 seconds and calls target Method: on self with one argument, which is a pointer to the NSTimer instance.
If you then want to look in more detail at the method you can refer back to the docs for more information, but there is explanation around the code too.
Further executions/delays controlled by // return value from closure, which can be .
Seasoned Cocoa developers may snicker at the title of this post, because it’s probably obvious to them. Maybe I can save someone some head-scratching by relaying my tale. Now, I’ve been around the Cocoa block a few times, so I knew this to be the case (the docs state it explicitly), but I clearly hadn’t thought through the ramifications. Let’s say you have a window, isn’t called until the controller’s retain count is zero, and until the timer invalidates (which will be never, on a repeating timer), the controller’s retain count will never be zero.
The final result will look like this: You can get the full code here.
If you take a look at the Timer Programming Topics article, it’s divided into two parts: – Timers – Using Timers For articles that take this format, there is often an overview of the class and what it’s used for, and then some sample code on how to use it, in this case in the “Using Timers” section.
There are sections on “Creating and Scheduling a Timer”, “Stopping a Timer” and “Memory Management”.
However, when you use a repeating timer and forget about retaining, this means trouble.
This post includes 2 ways applied by my team to deal with that issue.
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Each i OS application creates at least one NSThread object (the Main Thread) which represents the thread of execution of the application code.