The image set for button stays blank/white

Question

What I want to do is change the image when I click on the button. This button works well but the image in my button stays blank. I have done some serious research before posting.

I looked at this first Setting an image for a UIButton in code. While I wasn't sure if my image was nil or not I followed this instruction and this confirms me that my image isn't nil. I even did this and I made sure again that the images where present in the Assets folder.

Here is what I get from my console:

2017-04-12 15:57:00.826779+0800 UIImage: 0x170284a10, {64, 64}

2017-04-12 15:57:00.976058+0800 UIImage: 0x1702808c0, {64, 64}

2017-04-12 15:57:01.110049+0800 UIImage: 0x170285140, {64, 64}

2017-04-12 15:57:01.275860+0800 UIImage: 0x170280910, {64, 64}

I have this:

In the .h file

- (IBAction)powerButtonAction:(UIButton*)sender;

@property (weak, nonatomic) IBOutlet UIButton *powerButton;

In the .m file

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


   if (sender.selected) {
       UIImage *powerButtonImage = [UIImage imageNamed:@"power_off.png"];
       [powerButton setImage:powerButtonImage forState:UIControlStateNormal];
       [self.view addSubview:powerButton];
       NSLog(@"%@",powerButtonImage);
       [selectedDevice setPower:powerButton.selected];
       sender.selected = NO;
   } else {
       UIImage *powerButtonImage = [UIImage imageNamed:@"power_on.png"];
       [powerButton setImage:powerButtonImage forState:UIControlStateSelected];
       [self.view addSubview:powerButton];
       NSLog(@"%@",powerButtonImage);
       [selectedDevice setPower:!powerButton.selected];
       sender.selected = YES;
   }
}

check this once http://stackoverflow.com/questions/16909753/how-to-programmatically-set-my-uibutton-image-to-redraw — Anbu.Karthik, Apr 12 '17 at 08:17
Are you insert image in asset or simple are adding in supporting file Please confirm — Lalit kumar, Apr 12 '17 at 08:17
if it is in assest then use direct `power_on` in this place of `power_on.png` — Anbu.Karthik, Apr 12 '17 at 08:20
I checked the link and made the changes, still have the same problem. And I add the images in the Assets.xcassets folder. I have other images in my app who works well. — F.Chen, Apr 12 '17 at 08:39
Why don't you set image for power button for button state selected ? try to set image for selected state of button with [powerButton setImage:powerButtonImage forState:UIControlStateSelected]; — Pankaj K., Apr 12 '17 at 08:46
in else part you are setting button state from normal to selected so you also need to provide image for selected state. please check it. — Pankaj K., Apr 12 '17 at 08:48
There is one more easy way is u can change image in story board for diffrent state like default and selected , so only u have to pass UIButton State. — Ravi Panchal, Apr 13 '17 at 05:57
Your Power Button having Outlet so why u are adding in subview? — Ravi Panchal, Apr 13 '17 at 06:03
@ravi.p I didn't know you could change image for different states. It is working now! Thanks a lot! — F.Chen, Apr 13 '17 at 06:26
@ravi.p Yes go on, helped me a lot! It has been days I am looking how to get it work! — F.Chen, Apr 13 '17 at 07:56

Yatendra · Answer 1 · 2017-04-12T09:15:19.250

0

You have to change only these lines

 -(void)viewDidLoad {
        UIImage *powerButtonImage = [UIImage imageNamed:@"power_off.png"];
        [powerButton setImage:powerButtonImage forState:UIControlStateNormal];
        UIImage *powerButtonImage2 = [UIImage imageNamed:@"power_on.png"];
         [powerButton setImage:powerButtonImage2 forState:UIControlStateSelected];
        [self.view addSubview:powerButton];
    }

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


  sender.selected = !sender.selected;

}

edited Apr 12 '17 at 09:15

answered Apr 12 '17 at 08:56

Yatendra

1,310
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It is what @Prince suggested and I made the changes but still, the images stays white/blanc. What I find strange it's, that my console shows me that the images are there. {64, 64} is the size of my images. – F.Chen Apr 12 '17 at 09:00
@F.Chen if my previous answer not working then try with my new answer once – Yatendra Apr 12 '17 at 09:15

score 0 · Accepted Answer · answered Apr 13 '17 at 12:20

0

You can achieve this using storyBoard

Easiest way

answered Apr 13 '17 at 12:20

Ravi Panchal

1,285
10
22

score -1 · Answer 3 · answered Apr 12 '17 at 08:22

-1

it think you should add frame

powerButton.frame =CGRectMake(x, y , width, height);

answered Apr 12 '17 at 08:22

Return Zero

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The image set for button stays blank/white

3 Answers3