Question

I am using Xcode to create a Cocoa app for Mac OSX written in Objective-C.

Here is my code:

-(IBAction)clickToLaunchAppButtonClicked:(id)sender; {
//I want to hide the click to load app button
[clickToLoadButton setEnabled:NO];
[clickToLoadButton setHidden:YES];

//***I want to make the app wait for 1 second (This is where I'm stuck!)***

//I want to show the loading label
[loadingLabel setEnabled:YES];
[loadingLabel setHidden:NO];

//I want to show the loading progress bar and initialize it
[loadingProgressBar setHidden:NO];
[loadingProgressBar startAnimation:self];

//***I want to make the app wait for 3 seconds (Again, I don't know how to do this!)***

//I want to stop the loading progress bar animation
[loadingProgressBar stopAnimation:self];

//I want to hide the loading progress bar and loading label
[loadingLabel setHidden:YES];
[loadingLabel setEnabled:NO];
[loadingLabel setHidden:YES];
}

How can I make the app wait/pause for a few seconds? I tried the wait(), delay() or pause() functions, but they freeze the app, which is not what I want. Should I use an NSTimer? If so, please give me a simple way to implement it.

Answer 1

You can place the code you want to run on the 3 second delay in another method (delayedLoad) and use performSelector: withObject: afterDelay:

[self performSelector:@selector(delayedLoad) withObject:nil afterDelay:3.0];

EDIT – spelling it out more in response to your comment

to create the other method, include this code in the same .m file (AppDelegate.m or similar)

-(void)delayedLoad
{

//I want to stop the loading progress bar animation
[loadingProgressBar stopAnimation:self];

//I want to hide the loading progress bar and loading label
[loadingLabel setHidden:YES];
[loadingLabel setEnabled:NO];
[loadingLabel setHidden:YES];
}

And your existing method becomes

-(IBAction)clickToLaunchAppButtonClicked:(id)sender; {
//I want to hide the click to load app button
[clickToLoadButton setEnabled:NO];
[clickToLoadButton setHidden:YES];

//***I want to make the app wait for 1 second (This is where I'm stuck!)***

//I want to show the loading label
[loadingLabel setEnabled:YES];
[loadingLabel setHidden:NO];

//I want to show the loading progress bar and initialize it
[loadingProgressBar setHidden:NO];
[loadingProgressBar startAnimation:self];
[self performSelector:@selector(delayedLoad) withObject:nil afterDelay:3.0];
}

This is how you implement the 3 second delay. Hopefully you can extend this to implement the 1 second delay