Two action methods for an UIButton; next track and seek forward:

Question

I am creating a music player application and it need that 2 actions to be called from a single button, one to skip to next track by touch up inside event and other to fast forward the curenttrack incase of a 'long press'. I don't know which event is pointing to this long press, i thought it to be touch down, but it worked only while holding the button. When i released the button, the track was skipped to next item. pls help

AVAudioPlayer *appSoundPlayer;// declared in .h file

In m file, the method:

-(void)seekForwards{
NSTimeInterval timex;
timex = appSoundPlayer.currentTime;
        timex = timex+5; // forward 5 secs

        appSoundPlayer.currentTime = timex;
        timex = 0;
}

Answer 1

Personally I'd just track the button's state with an integer on your view controller or within a button subclass. If you track what the button is doing you can control what each of the actions do. In your .h file put in some stuff like this:

enum {
    MyButtonScanning,
    MyButtonStalling,
    MyButtonIdle
};



@interface YourClass : UIViewController {
    NSInteger buttonModeAt;
}
@property (nonatomic) NSInteger buttonModeAt;
-(IBAction)buttonPushedDown:(id)sender;
-(void)tryScanForward:(id)sender;
-(IBAction)buttonReleasedOutside:(id)sender;
-(IBAction)buttonReleasedInside:(id)sender;
@end

And then in your .m file throw in some of this stuff:

@implementation YourClass
///in your .m file
@synthesize buttonModeAt;


///link this to your button's touch down
-(IBAction)buttonPushedDown:(id)sender {
    buttonModeAt = MyButtonStalling;
    [self performSelector:@selector(tryScanForward:) withObject:nil afterDelay:1.0];
}

-(void)tryScanForward:(id)sender {
    if (buttonModeAt == MyButtonStalling) {
        ///the button was not released so let's start scanning
        buttonModeAt = MyButtonScanning;

        ////your actual scanning code or a call to it can go here
        [self startScanForward];
    }
}

////you will link this to the button's touch up outside
-(IBAction)buttonReleasedOutside:(id)sender {
    if (buttonModeAt == MyButtonScanning) {
        ///they released the button and stopped scanning forward
        [self stopScanForward];
    } else if (buttonModeAt == MyButtonStalling) {
        ///they released the button before the delay period finished
        ///but it was outside, so we do nothing
    }

    self.buttonModeAt = MyButtonIdle;
}

////you will link this to the button's touch up inside
-(IBAction)buttonReleasedInside:(id)sender {
    if (buttonModeAt == MyButtonScanning) {
        ///they released the button and stopped scanning forward
        [self stopScanForward];
    } else if (buttonModeAt == MyButtonStalling) {
        ///they released the button before the delay period finished so we skip forward
        [self skipForward];
    }

    self.buttonModeAt = MyButtonIdle;

}

After that just link the button's actions to what I've noted in the comments before the IBactions. I haven't tested this but it should work.

Answer 2

you can subclass your button's class and play a bit around UIResponder's methods. For example, in touchesBegan method you can fire some timer and call method which will move throw your file and invalidate this timer in the toucesEnded method