如何在按下按钮时更改按钮的颜色，并在按下其他按钮时重置为原始颜色？

Question

So I have two gray UIButton , button1 and button2. I want to change the color of the button when I press it to red and back to gray when I press the other button.

I used this code:

UIButton *btn = (UIButton *)sender;
[btn setBackgroundColor:[UIColor redColor]];

But it makes both buttons red.

How do I make it so that if button1 is red, it will change back to gray when I press button2?

Answer 1

You are going to want to make two separate buttons. By the look of your code you only declared only one button.

Declare both buttons in your interface, initialize them in the ViewDidLoad() method.

Set 2 different targets for each of the buttons so when one is clicked you can set the other buttons colour.

Answer 2

What I am getting from this is that both buttons are connected to the same action/method, which contains the code you gave. The easiest way to do what you specified is to have two different actions/methods, and connect each button to a different method. Connect button1 to button1Pressed and connect button2 to button2Pressed.

In .h put:

{
    //connect these buttons up either via interface builder or through code
    IBOutlet UIButton* button1;
    IBOutlet UIButton* button2;
}

- (IBAction)button1Pressed:(id)sender;
- (IBAction)button2Pressed:(id)sender;

In .m put:

//connect this method to "touch up inside" on button1
- (IBAction)button1Pressed:(id)sender
{
    //makes button1 red
    [button1 setBackgroundColor:[UIColor redColor]];
}

//connect this method to "touch up inside" on button2
- (IBAction)button2Pressed:(id)sender
{
    //changes button1 back to gray
    [button1 setBackgroundColor:[UIColor grayColor]];
}

Hope this helps!

Answer 3

There is many way to solve such issue, in your case we do not really know how you are instantiating your UIButton . The following purpose you one of the possible solution using tag:

First you should define your button in your header:

@implementation _4644518ViewController {
    UIButton *btn1;
    UIButton *btn2;
}

Then, you should implement them in your view and attach to them the tapped method:

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    btn1 = [[UIButton alloc] initWithFrame:CGRectMake(5, 5, 100, 30)];
    [btn1 setTag:101];
    [btn1 setTitle:@"btn1" forState:UIControlStateNormal];
    btn1.backgroundColor = [UIColor lightGrayColor];
    [btn1 addTarget:self action:@selector(btnTapped:) forControlEvents:UIControlEventTouchUpInside];

    [self.view addSubview:btn1];

    btn2 = [[UIButton alloc] initWithFrame:CGRectMake(5, 40, 100, 30)];
    [btn2 setTag:102];
    [btn2 setTitle:@"btn2" forState:UIControlStateNormal];
    btn2.backgroundColor = [UIColor lightGrayColor];
    [btn2 addTarget:self action:@selector(btnTapped:) forControlEvents:UIControlEventTouchUpInside];

    [self.view addSubview:btn2];
}

The last thing to do is to implement your btnTapped method:

- (void)btnTapped:(id)sender
{
    if ([sender tag] == 101) {
        btn1.backgroundColor = [UIColor redColor];
        btn2.backgroundColor = [UIColor lightGrayColor];
    } else if([sender tag] == 102) {
        btn1.backgroundColor = [UIColor lightGrayColor];
        btn2.backgroundColor = [UIColor redColor];
    }
}

As I mentioned earlier, there is many way to perform such algorithm, but I like this one since we don't know many things about your background application and this one will be easy to custom for you.

Answer 4

Create two buttons btn1 & btn2 .

@property (weak, nonatomic) IBOutlet UIButton *btn1;
@property (weak, nonatomic) IBOutlet UIButton *btn2;
- (IBAction)btnClick:(id)sender;

Both btn1 & btn2 should be connected to btnClick . Below code will do the rest of your work

- (IBAction)btnClick:(id)sender {

    if (self.btn1 == sender) {

        [self.btn1 setBackgroundColor:[UIColor redColor]];
        [self.btn2 setBackgroundColor:[UIColor grayColor]];

    }else{

        [self.btn1 setBackgroundColor:[UIColor grayColor]];
        [self.btn2 setBackgroundColor:[UIColor redColor]];

    }

}