Passing parameters on button action:@selector

Edit. Found a neater way!

One argument that the button can receive is (id)sender. This means you can create a new button, inheriting from UIButton, that allows you to store the other intended arguments. Hopefully these two snippets illustrate what to do.

  myOwnbutton.argOne = someValue
  [myOwnbutton addTarget:self action:@selector(buttonTouchUpInside:) forControlEvents:UIControlEventTouchUpInside];

and

- (IBAction) buttonTouchUpInside:(id)sender {
  MyOwnButton *buttonClicked = (MyOwnButton *)sender; 
  //do as you please with buttonClicked.argOne
}

This was my original suggestion.

There is a way to achieve the same result, but it's not pretty. Suppose you want to add a parameter to your navigate method. The code below will not allow you to pass that parameter to navigate.

[button addTarget:self action:@selector(navigate) forControlEvents:UIControlEventTouchUpInside];

To get around this you can move the navigate method to a class of it's own and set the "parameters" as attributes of that class...

NavigationAid *navAid = [[NavigationAid alloc] init];
navAid.firstParam = someVariableOne
navAid.secondParam = someVariableTwo
[button addTarget:navAid action:@selector(navigate) forControlEvents:UIControlEventTouchUpInside];

Of course you can keep the navigate method in the original class and have it called by navAid, as long as it knows where to find it.

NavigationAid *navAid = [[NavigationAid alloc] init];
navAid.whereToCallNavigate = self
navAid.firstParam = someVariableOne
navAid.secondParam = someVariableTwo
[button addTarget:navAid action:@selector(navigate) forControlEvents:UIControlEventTouchUpInside];

Like I said, it's not pretty, but it worked for me and I haven't found anyone suggesting any other working solution.


I found solution. The call:

-(void) someMethod{
    UIButton * but;
    but.tag = 1;//some id button that you choice 
    [but addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside]; 
}

And here the method called:

-(void) buttonPressed : (id) sender{
    UIButton *clicked = (UIButton *) sender;
    NSLog(@"%d",clicked.tag);//Here you know which button has pressed
}

I made a solution based in part by the information above. I just set the titleLabel.text to the string I want to pass, and set the titleLabel.hidden = YES

Like this :

    UIButton *imageclick = [[UIButton buttonWithType:UIButtonTypeCustom] retain];
    imageclick.frame = photoframe;
    imageclick.titleLabel.text = [NSString stringWithFormat:@"%@.%@", ti.mediaImage, ti.mediaExtension];
    imageclick.titleLabel.hidden = YES;

This way, there is no need for a inheritance or category and there is no memory leak


You can sub-class a UIButton named MyButton, and pass the parameter by MyButton's properties.

Then, get the parameter back from (id)sender.


Add the hidden titleLabel to the parameter is the best solution.

I generated a array arrUrl which store the NSURL of the mov files in my phone album by enumerate assets block.

After that, I grab on Frame, lets say, get the frame at 3:00 second in the movie file, and generated the image file from the frame.

Next, loop over the arrUrl, and use program generate the button with image in the button, append the button to subview of the self.view.

Because I have to pass the movie Url to playMovie function, I have to assign the button.titleLabel.text with one movie url. and the the button events function, retrieve the url from the buttontitleLable.txt.

-(void)listVideos

{
   for(index=0;index<[self.arrUrl count];index++{
      UIButton *imageButton = [UIButton buttonWithType:UIButtonTypeCustom];
      imageButton.frame = CGRectMake(20,50+60*index,50,50);

      NSURL *dUrl = [self.arrUrl objectAtIndex:index];

      [imageButton setImage:[[UIImage allow] initWithCGImage:*[self getFrameFromeVideo:dUrl]] forState:UIControlStateNormal];
      [imageButton addTarget:self action:@selector(playMovie:) forControlEvents:UIControlEventTouchUpInside];
      imageButton.titleLabel.text = [NSString strinfWithFormat:@"%@",dUrl];
      imageButton.titleLabel.hidden = YES;

      [self.view addSubView:imageButton];
   }
}

-(void)playMovie:(id) sender{
   UIButton *btn = (UIButton *)sender;
   NSURL *movUrl = [NSURL URLWithString:btn.titleLabel.text];
   moviePlayer = [[MPMoviePlayerViewController alloc] initWithContentURL:movUrl];
   [self presentMoviePlayerViewControllerAnimated:moviePlayer];
}

-(CGIImageRef *)getFrameFromVideo:(NSURL *)mUrl{
   AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:mUrl option:nil];
   AVAssetImageGenerator *generator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
   generator.appliesPreferredTrackTransform = YES;
   NSError *error =nil;
   CMTime = CMTimeMake(3,1);
   CGImageRef imageRef = [generator copyCGImageAtTime:time actualTime:nil error:&error];
   if(error !=nil) {
      NSLog(@"%@",sekf,error);
   }

   return @imageRef;
}