How to detect a button click - logic error code provided

Question

What I want to do is, when I click the button once it should get highlighted (I am loading an image to show the highlighted effect), and when I click the button again (for the second time) it should remove the highlighted image and add a normal image. It should also add and remove elements from a Mutable Array.

But what is happening is that, when I click (once or several times) it only adds images, and does not remove any. Help me please

Code
I am adding a button. The below 2 lines are placed in the viewdidload method

UIButton *but= [UIButton buttonWithType:UIButtonTypeRoundedRect];
    // then i set the size etc, and do the following

        [but addTarget:self action:@selector(butclick:) forControlEvents:UIControlEventTouchUpInside];

    -(void)butclick:(id)sender{

        if([sender isSelected]==NO) {
            [sender setBackgroundImage:[UIImage imageNamed:@"highlighted.png"] forState:UIControlStateNormal];
            [sender setSelected:YES];

            [self.mutArry addObject:[sender titleForState:UIControlStateSelected]];

        } else {
            [sender setBackgroundImage:[UIImage imageNamed:@"nothighlighter.png"] forState:UIControlStateNormal];
            [sender setSelected:NO];
            [self.mutArry removeObject:[sender titleForState:UIControlStateSelected]];

        }

}

Answer 1

u might want to use a BOOL (like a flag) to use it instead of using the highlight idea.

toggle it with each press, and according to its value perform ur operation, it will always add a value once and remove a value the next press. the first is according to what the initial value of that flag is.

    if (flag)
    {
    //add your object and set to highlight
       flag = NO;
    }else
    {
       flag = yes;
       //remove object and set to not highlighted
    }

set the flag to NO when when it was found true, and to YES when it was found false. ensures it will keep changing

Answer 2

Have the following property defined and synthesized in that class

BOOL selected;

in viewDidLoad, set is to false

self.selected = NO;

Now do the following:

-(void)butclick:(id)sender{

    if(!self.selected) {
        [sender setBackgroundImage:[UIImage imageNamed:@"highlighted.png"] forState:UIControlStateNormal];
        self.selected =  YES;

        [self.mutArry addObject:[sender titleForState:UIControlStateSelected]];

    } else {
        [sender setBackgroundImage:[UIImage imageNamed:@"nothighlighter.png"] forState:UIControlStateNormal];
        self.selected = NO;
        [self.mutArry removeObject:[sender titleForState:UIControlStateSelected]];

    }

}