Keeping a UIButton selected after a touch

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After my user clicks a button, I'd like that button to stay pushed during the time that I perform a network operation. When the network operation is complete, I want the button to return to its default state.

I've tried calling -[UIButton setSelected:YES] right after the button push (with a corresponding call to -[UIButton setSelected:NO] after my network op finishes) but it doesn't seem to do anything. Same thing if I call setHighlighted:.

I suppose I could try swapping out the background image to denote a selected state for the duration of the network op, but that seems like a hack. Any better suggestions?

Here's what my code looks like:

- (IBAction)checkInButtonPushed
{
    self.checkInButton.enabled = NO;
    self.checkInButton.selected = YES;
    self.checkInButton.highlighted = YES;
    [self.checkInActivityIndicatorView startAnimating];
    [CheckInOperation startWithPlace:self.place delegate:self];
}

- (void)checkInCompletedWithNewFeedItem:(FeedItem*)newFeedItem wasNewPlace:(BOOL)newPlace possibleError:(NSError*)error;
{
    [self.checkInActivityIndicatorView stopAnimating];
    self.checkInButton.enabled = YES;
    self.checkInButton.selected = NO;
    self.checkInButton.highlighted = NO;
}
9 Answers

Try using NSOperationQueue to achieve this. Try out code as follows:

[[NSOperationQueue mainQueue] addOperationWithBlock:^{
    theButton.highlighted = YES;
}];

Hope this helps.

Use a block so you don't have to build a whole separate method:

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 0), dispatch_get_main_queue(), ^{
    theButton.highlighted = YES;
});

Update

To be clear you still need to set the background (or normal image) for the combination states as well as the regular ones like sbrocket says in the accepted answer. At some point your button will be both selected and highlighted, and you won't have an image for that unless you do something like this:

[button setBackgroundImage:someImage forState (UIControlStateHighlighted|UIControlStateSelected)];

Otherwise your button can fall back to the UIControlStateNormal image for the brief selected+highlighted state and you'll see a flash.

I have another way ...if you don't want to use images, and you want the effect of a pressed button, You can subclass the Button and here's my code:

in the .h File:

@interface reservasButton : UIButton {

BOOL isPressed;
}
 @end

In the .m File:

#import <QuartzCore/QuartzCore.h>


 @implementation reservasButton

 -(void)setupView {  //This is for Shadow

    self.layer.shadowColor = [UIColor blackColor].CGColor;
    self.layer.shadowOpacity = 0.5; 
    self.layer.shadowRadius = 1;    
    self.layer.shadowOffset = CGSizeMake(2.0f, 2.0f); //comment
    //   self.layer.borderWidth = 1;
    self.contentVerticalAlignment   = UIControlContentVerticalAlignmentCenter;
    self.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;

    // [self setBackgroundColor:[UIColor whiteColor]];

    //  self.opaque = YES;


}

-(id)initWithFrame:(CGRect)frame{
    if((self = [super initWithFrame:frame])){
        [self setupView];
    }

    return self;
}

-(id)initWithCoder:(NSCoder *)aDecoder{
    if((self = [super initWithCoder:aDecoder])){
        [self setupView];
    }

    return self;
}

//Here is the important code

 -(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{


  if (isPressed == FALSE) {

      self.contentEdgeInsets = UIEdgeInsetsMake(1.0,1.0,-1.0,-1.0);
      self.layer.shadowOffset = CGSizeMake(1.0f, 1.0f);
      self.layer.shadowOpacity = 0.8;

      [super touchesBegan:touches withEvent:event];

      isPressed = TRUE;

     }
     else {

         self.contentEdgeInsets = UIEdgeInsetsMake(0.0,0.0,0.0,0.0);
         self.layer.shadowOffset = CGSizeMake(2.0f, 2.0f);
         self.layer.shadowOpacity = 0.5;

         [super touchesEnded:touches withEvent:event];

         isPressed = FALSE;

     }


 } `

Here is a C# / MonoTouch (Xamarin.iOS) implementation using approaches presented above. It assumes you have set the Highlighted image state already, and configures the selected and selected|highlighted states to use the same image.

var selected = button.BackgroundImageForState(UIControlState.Highlighted);
button.SetBackgroundImage(selected, UIControlState.Selected);
button.SetBackgroundImage(selected, UIControlState.Selected | UIControlState.Highlighted);
button.TouchUpInside += delegate
{
    NSTimer.CreateScheduledTimer(TimeSpan.FromMilliseconds(0), delegate
    {
        button.Highlighted = true;
        NSTimer.CreateScheduledTimer(TimeSpan.FromMilliseconds(200), delegate
        {
            button.Highlighted = false;
        });
    });
};
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