IOS: one IBAction for multiple buttons

In my project I must control action of 40 butt开发者_StackOverflow中文版ons, but I don't want to create 40 IBAction, can I use only a IBAction, how?

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If you're using interface builder to create the buttons, simply point them at the same IBAction in the relevant class.

You can then differentiate between the buttons within the IBAction method either by reading the text from the button...

- (IBAction)buttonClicked:(id)sender {
    NSLog(@"Button pressed: %@", [sender currentTitle]);    
}

...or by setting the tag property in Xcode and reading it back via [sender tag]. (If you use this approach, start the tags at 1, as 0 is the default and hence of little use.)

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-(IBAction)myButtonAction:(id)sender {
    if ([sender tag] == 0) {
        // do something here
    }
    if ([sender tag] == 1) {
        // Do something here
    }    
}

// in Other words

-(IBAction)myButtonAction:(id)sender {
        switch ([sender tag]) {
        case 0:
            // Do something here
            break;
        case 1:
           // Do something here
             break;
       default:
           NSLog(@"Default Message here");
            break;
}

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Set all the buttons to use that one action. Actions generally have a sender parameter, which you can use to figure out which button is calling the action. One popular way to tell the difference between buttons is to assign a different value to each button's tag property. So you might have 40 buttons with tags ranging from 1 to 40. (0 probably isn't a great choice for a tag since that's what the default value is, and any button for which you forget to set the tag will have 0 as the tag value.)

This technique is most useful when all the buttons do approximately the same thing, like the buttons on a calculator or keyboard. If each of the buttons does something completely different, then you still end up with the equivalent of 40 methods, but you substitute your own switch statement for Objective-C's messaging system. In that case, it's often better just to spend the time to create as many actions as you need an assign them appropriately.

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Sure. Just connect all buttons to the same action method in Interface Builder. Use the method's sender argument (possibly in conjunction with the buttons' tag property) to identify which button is sending the event.

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Just use one IBAction and assign it to all your buttons.

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Just used the above method myself , had a selection of buttons but converted them all and used switch case instead

-(IBAction)buttons:(id)sender
{

    switch ([sender tag])

    {

        case 0 :

    }
}

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Seems like you are getting all the answers you need, but I wanted to add to everyone else's answers.

Whether you want to use one IBAction or 40 actions is up to what you want the buttons to do. If all the buttons do completely different things, you need all separate IBActions, but if you want all of them to do the same thing, you can use just one. I need more details of those buttons and action, but you probably have title for each button, so you can use that to differentiate each button and create a message or something that's being customized by the particular button pressed. Here is the example. Each time a button is pressed, a label displays a message that say "i.e.title of the button" pressed.

By doing it this way, you don't need to do switch case with all 40 patterns. You can still display or do something that's individualized by the button pressed with just 2-3 lines of code.

- (IBAction)button_Clicked:(UIButton *)sender {

    //Get the buttons' titles.
    NSString *title =[sender titleForState:UIControlStateNormal];

    //Construct a message that includes the *title. 
    NSString *plainText=[NSString stringWithFormat:@"%@ button pressed.", title];

    //Assigns the *plainText to the label. 
    self.Label.text=plainText;

}
@end