4
votes

I have a tutorial for my app, which should display only the first time the app is opened and should be tapped to dismiss.

I am initializing a UITapGestureRecognizer in my viewDidLoad:

tapper_tut = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTap:)];
tapper_tut.cancelsTouchesInView = FALSE;
[self.view addGestureRecognizer:tapper_tut];

and I have an IBAction to detect the tap and set the tutorial to hidden:

- (IBAction)dismiss_tut{
    if (????????????????) {
        _tutorial.hidden = YES;
    }
}

But I have no idea what to put in the if statement condition, or if this is even that right way to go about this.

How would I dismiss a UIImageView on a tap?

4
why you want if statement?Vaibhav Saran

4 Answers

12
votes
UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
[self.view addGestureRecognizer:gr];
// if not using ARC, you should [gr release];
// mySensitiveRect coords are in the coordinate system of self.view


- (void)handleGesture:(UIGestureRecognizer *)gestureRecognizer {
    CGPoint p = [gestureRecognizer locationInView:self.view];
    if (CGRectContainsPoint(mySensitiveRect, p)) {
        NSLog(@"got a tap in the region i care about");
    } else {
        NSLog(@"got a tap, but not where i need it");
    }
}
3
votes

You can make viewDidLoad like this

- (void)viewDidLoad 
  { 
      [super viewDidLoad];
      self.view.backgroundColor = [UIColor whiteColor];

      /* Create the Tap Gesture Recognizer */
      self.tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
                                   action:@selector(handleTaps:)]; 

     /* The number of fingers that must be on the screen */
      self.tapGestureRecognizer.numberOfTouchesRequired = 1;

     /* The total number of taps to be performed before the gesture is recognized */
      self.tapGestureRecognizer.numberOfTapsRequired = 1;

     /* Add this gesture recognizer to the view */
     [self.view addGestureRecognizer:self.tapGestureRecognizer];
  }

To detect the taps you can make the method like this.

- (void) handleTaps:(UITapGestureRecognizer*)paramSender
  {
      NSUInteger touchCounter = 0; 
      for (touchCounter = 0;touchCounter < paramSender.numberOfTouchesRequired;touchCounter++)
      {
            CGPoint touchPoint =[paramSender locationOfTouch:touchCounter inView:paramSender.view];
            NSLog(@"Touch #%lu: %@",(unsigned long)touchCounter+1, NSStringFromCGPoint(touchPoint));
      }
  }
2
votes

you have to declare .h file as "UIGestureRecognizerDelegate"

you have getting tap of gesture as two way as given below steps.

1) Call delegate method of GestureRecognizer (not given action )

UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:nil]; // not given  action.
recognizer.numberOfTouchesRequired=1;// here how many tap you want set it 
[self.view addGestureRecognizer:recognizer];
recognizer.delegate = self;

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
 {
     //whatever you want write code here
    return NO;
  }

2) given action

 UITapGestureRecognizer *oneTouch=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(Addphoto)];
 [oneTouch setNumberOfTouchesRequired:1];
 [self.view addGestureRecognizer:oneTouch];

 -(IBAction)Addphoto
 {
     //whatever you want write code here
 }

may be it will help .

0
votes

I think u need to detect the first time launch of the application which u can do with following

![[NSUserDefaults standardUserDefaults] boolForKey:@"HasLaunchedOnce"]

Put this in your if statement .