I'm trying to change the image button just in the moment that the button is pressed. When released, i want go back to the original.
I read some posts here, but it's not working.
Is it possible do it in the GUI without programming?
I tried this:
-(IBAction) toggleUIButtonImage:(id)sender{
if ([sender isSelected]) {
[sender setImage:unselectedImage forState:UIControlStateNormal];
[sender setSelected:NO];
}else {
[sender setImage:selectedImage forState:UIControlStateSelected];
[sender setSelected:YES];
}
}
But what kind of sender events should i associated the function toggleUIButtonImage ?
Thanks
You can do it in interface builder by giving different settings to each button state config:
Or you can also change the 'settings' of the button in code by using 'UIButton' setImage:forState method.
[myButton setImage:highlightedImage forState:UIControlStateHighlighted];
Usually, you should do it by 'configuring' the button as described above and not by changing the sub views of the button manually as a response to user interaction. The reason it doesn't work for you is the inherent hidden behaviour of UIButton. You manually make the change of a subview of the button as a response to user interaction, but your change is changed back to what was defined in the settings of your button (according to the button's state). So it seems like your code doesn't do anything at all.
in the ViewDidLoad Method
set the property of
[[button setImage:[UIImage ImageNamed:#"unselectedImage.png"] forState: UIControlStateNormal];
[[button setImage:[UIImage ImageNamed:#"selectedImage.png"] forState: UIControlStateHighlighted ];
This can be done with Interface Builder, no code necessary.
Select your button in IB, go to the right sidebar, change the Type to Custom, make sure State Config is Default, and type in the name of your "regular image" reference in the Background Image text field.
Then change State Config to Highlighted, and type in the name of your "pressed image" reference in the Background Image text field.
In IB, you can set the image for the Highlighted (not Selected) state of the button. That should do it.
Look in the Button section of the Utilities pane, and select Highlighted from the State Config drop-down.
I'm losing my mind over this one. I have UIButton connected as Outlet. I want to change it's image. In the viewDidLoad function, I try to set the image like so:
[button1 setImage:[UIImage imageNamed:#"house.png"] forState:UIControlStateNormal];
Nothing happens. However, if I use ImagePicker, it somehow works. In the ImagePickers function "didFinishPickingImage", I repeat the exactly same command as above for setting image and it works, the image is displayed normally.
I've been thinking that maybe the button's image is not refreshing itself, but trying to call [button1 setNeedsDisplay], or [button1.imageView setNeedsDisplay] or even [button1.imageView.image setNeedsDisplay] does nothing.
Does anyone have any idea about this? I've wasted two hours by now and I'm really getting frustrated, because I'm certain that the reason must be so stupid it's unbelivable.
Please check your button type.
If your button type is "System" you should change it to "Custom"
Two things to do here:
#1, change your code to:
[button1 setImage:[UIImage imageNamed:#"house.png"] forState:UIControlStateNormal];
and #2
make sure your UIImage returns a valid image.
In other words,
UIImage * imageToSet = [UIImage imageNamed: #"house.png"];
if(imageToSet)
{
[button1 setImage:[UIImage imageNamed:#"house.png"] forState:UIControlStateNormal];
} else {
// if you see this line in your console, then you know where to look for a problem
NSLog( #"why is my image object nil?");
}
For anyone who will find themselves in a similar situation; I was using the mentioned button inside a custom cell for table view. However, the cells aren't loaded right away (i.e. inside viewDidLoad/viewWillAppear etc.), but inside the tableView:cellForRowAtIndexPath function. All my button variables were nil at that point. My solution was to load the image after the cell has been created and it has worked straight away afterwards.
Here are a couple additional notes. UIButton setImage: forState: is the correct method:
[button1 setImage:[UIImage imageNamed:#"house.png"] forState:UIControlStateNormal];
imageNamed is a great convenience method for grabbing the image, but make sure it returns an object. Forgetting to include the image file in the current target gets me all of the time.
[UIImage imageNamed:#"house.png"]
You also don't need the extension. The SDK works this out.
[UIImage imageNamed:#"house"]
And even though UIControlState is a bit mask, you cannot OR the values together. This does not not not work and I must must must remember this because it gets me every time I use the call.
// NO NO NO
[button1 setImage:[UIImage imageNamed:#"house"] forState:UIControlStateNormal|UIControlStateSelected];
// YES
[button1 setImage:[UIImage imageNamed:#"house"] forState:UIControlStateNormal];
[button1 setImage:[UIImage imageNamed:#"house"] forState:UIControlStateSelected];
Was getting the same problem when UIbutton was in UITableViewCell.
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setImage:[UIImage imageNamed:#"detail.png"] forState:UIControlStateNormal];
should work in UITableViewCell
Glad to know that the problem is solved but none of the answers actually addresses the problem.
Generally, if the code is correct, then the error shifts from "syntax error" to the "logical error" category. There is no definite guide to handle it but here is a small checklist that can help anyone to troubleshoot their code.
1) The IBOutlet is not connected or renamed.
2) Make sure that the UIButton type is custom.
3) The image is set (more than once), somewhere else in the code.
4) You are trying to set the Image through any sync method which is not using the main thread. (There are several threads on that alone).
5) If you are nesting the images as subviews, make sure the problem isn't with their parent view.
6) If it is appearing in Simulator but not in the device, It's a lettercase (Uppercase, lowercase difference in the code and the filename.
7) Modern simulators works with very low GPU memory on older machines. You can tweak the simlator options to make it appear. E.g (Command + Right Arrow) twice to change the simulator orientation and your changes will appear.
There are few other but common pitfalls where developers usually overlook
1) The image doesn't exist OR you are making a spelling mistake.
2) The filetype is different than mentioned. (JPG, PNG).
Last thing you'll want to check - make sure you're setting the image on the main thread! Just ran into an issue where I was setting a button image in a callback from ALAssetLibrary (fetching images from photo library). The image wouldn't update until I tapped the button. Turns out the callback was happening off main...
for those having issues with system images not appearing, just use systemName: instead of named
if let starImg = UIImage(systemName: "star.fill") {
button.setImage(starImg, for: .normal)
}
It's for ios13 and later...
For me it was to move the line:
[button1 setImage:[UIImage imageNamed:#"house.png"] forState:UIControlStateNormal];
from awakeFromNib method
to viewDidLoad method
I guess,
don't create like this
UIButton *nextButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
by this create method ,UIButton is create by use default type,so your background image is not work.
try this,
UIButton *nextButton = [[UIButton alloc] initWithFrame:CGRectMake(9, 154, 300, 48)];
or other,except buttonWithType
This is happening because the state of the Button doesn't stays selected once clicked by default.
I solved it by making an IBaction on that button click and toggling the selected state.
-(IBAction) checkButtonClicked:(id)sender{
checkButton.selected = !checkButton.selected;
}
In my case, it is drawn by custom animation code and not set by the image, so it doesn't work by setting any image, it has to change the animation code.
With images, you have to import them into the project not as references but as copies. So when you go to add files to project, choose "Create groups" instead of "Create folder references". Also make sure "Copy items if needed" is checked.
This is confusing because importing as references works when you are using images as textures (e.g. for Sprites). However, it doesn't work when you want to use images for buttons (e.g. for using image name in [UIImage imageNamed:#"house.png"]
I faced this same issue of the image not being shown on the UIButton.
I had to change this line -
myButton.setImage(<my_UIImage_object>, for: [.normal, .focused])
to this -
myButton.setImage(<my_UIImage_object>, for: .normal)
I'm trying to change the title of a button when the user press on it with the following code:
- (IBAction) hideKB: (UIButton *) sender {
sender.titleLabel.text = #"↓";
}
But when I click the app crashes and I can't understand why.
Removing the sender stuff, the button works with no problems.
The correct method signature for an action is
- (IBAction)action:(id)sender
Your app is crashing because your object is being sent a message it doesn't understand.
Try replacing your code with something along the lines of:
- (IBAction)hideKB:(id)sender {
UIButton *button = (UIButton *)sender;
[button setTitle:#"↓" forState:UIControlStateNormal];
}
As you may notice I've also changed the line that sets the button title. This is because you should never manipulate a UIButton's titleLabel property directly, but rather you should be using the appropriate setter method as shown above.
Edit: To clarify, most controls will allow you to use dot notation to edit the text property of their titleLabel. However, UIButton instances support different titles (as well as images and background images) depending on the state they're in.
If you're wondering why a UIButton could be in one of several different states, a good example you often see is buttons that are "greyed out". What this means is that those buttons are in the UIControlStateDisabled state. You can find a list of all the possible states for a control in the documentation.
Try using
- (void)setTitle:(NSString *)title forState:(UIControlState)state
e.g.
[sender setTitle:"↓" forState:UIControlStateNormal];
you can try with:
[(UIButton *)sender setTitle: #"↓"" forState: UIControlStateNormal];
For more information, you can refer to setTitle:forState: in UIButton Class Reference
Hope this helps.
I am new to iphone.I created a UIButton programmatically,which is used to exit from subView to PreviousView.
For this, I written code as follows:
-(IBAction)button99:(id)sender
{
[myview1 removeFromSuperview];
}
But the above event is not fired.What can i do for this?
Can any one suggest me proper code.
Thanks in Advance.
Add this to your code,
[yourButton addTarget:self action:#selector(button99:) forControlEvents:UIControlEventTouchUpInside];
To use the button with (IBAction) you should use Interface Builder to link that method to the actual button. If you link that to the button the method will be fired.
Be sure to declare the IBAction in the .h file also..
And indeed Simon is correct when you wish to do it programmatically..!
I have UIButton that I set the background image for three states, normal, highlighted, and disabled, all with the following format:
[button setBackgroundImage:buttonBGD forState:UIControlStateDisabled];
My problem is, that when the button is disabled, the iPhone chooses to lighten the image for me. Which isn't desired. But if I tell it:
[button setAdjustsImageWhenDisabled:NO];
Then the image doesn't change at all. How do I remove the automatic lightening of the image, and instead use just the original image I created?
Try:
[button setBackgroundImage:buttonBGD forState:UIControlStateNormal | UIControlStateDisabled]
If you want the same disabled image when the button is selected and disabled, then add:
[button setBackgroundImage:buttonBGD forState:UIControlStateSelected | UIControlStateDisabled];
Hope that helps!
Actually this are the constraints made by apple and as such there is no work around way. But u can try using the custom button and try using a bit more dark image then required in disabled state so that when it gets lightened then it is up to the mark as per your requirements.
Hope this helps.
Try removing the selected state while disabled:
[button setSelected:NO];