UIButton change background when tapped (programmatically) - ios

I have a custom UIButton but I am not able to make changing background or text color based on a quick tap. If something works, it's only on long press:
buton.isUserInteractionEnabled = true
buton.setTitle("text_normal", for: .normal)
buton.setTitle("text_highlighted", for: .highlighted)
buton.setTitle("text_selected", for: .selected)
buton.setTitle("text_focused", for: .focused)
The only text I can get is "text_highlighted" after holding the button ~1 second. But nothing happens on short tap.
But the action is triggered correctly:
let tap2 = UITapGestureRecognizer(target: self, action: #selector(handleTap))
buton.addGestureRecognizer(tap2)
#objc func handleTap(sender: UITapGestureRecognizer) {
print("click")
}
What I tried:
Adding custom
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
...
which is also triggered later. And combining with tocuhesEnded didn't change the color temporarily as well (maybe it was too quick).
I can't use UIButton(type: .system) as well - it's not system styled button.
Similar as with changing text this is not working as well:
self.setTitleColor(UIColor.gray, for: .normal)
self.setTitleColor(UIColor.yellow, for: .selected)
self.setTitleColor(UIColor.yellow, for: .highlighted)
self.setTitleColor(UIColor.yellow, for: .focused)
I can see yellow only when long pressed. I am looking for something like this, but it needs to work on quick tap as well.
Custom button is modifying layoutSubviews(), but not colors. Custom button contains default image and label. Whole button has rounded corners. But overall nothing special is in there.
I am not using any storyboard or XIB - everything is in Swift 4 programatically.
The button is supposed to lead to another ViewController, but I want to see the immediate feedback on click. Something like when created from storyboard: https://youtu.be/lksW12megQg?t=3m25s - not even simple alpha change works for me right now.

check isselected property of uibutton if button is selected then change the background color of button

Jen Jose was right - there was a problem with my parent class which was 'eating up' my touches. I confirmed this when moving it to different ViewController + I had the same issue with table, which couldn't handle touch events (https://stackoverflow.com/a/9248827/1317362)
EDIT:
To be precise - this button was in a UIScrollView.
Adding scrollView.delaysContentTouches = NO; solved the issue completely.
Details: https://stackoverflow.com/a/16650610/1317362

Related

UIButton Title Label Text Not Changing Using Storyboard or Programmatically

Xcode 12.0.1
I am trying to remove the title label text on a UIButton using the storyboard. I then plan on setting it programmatically. When removing the text via the storyboard, the preview shows the text removed. However, the text remains when I build and run the application.
Changing programmatically is not working either. I try to change in in the controllers viewDidLoad()
punchBtn.setTitle("Transfer", for: .normal)
punchBtn.setTitle("Transfer", for: .application)
punchBtn.setTitle("Transfer", for: .selected)
punchBtn.setTitle("Transfer", for: .reserved)
punchBtn.setTitle("Transfer", for: .highlighted)
punchBtn.setTitle("Transfer", for: .disabled)
punchBtn.setTitle("Transfer", for: .focused)
The interesting thing is the text is changing when the button is selected:
Any advice would be greatly appreciated.
In the file Main.strings you will find this word "punch".
change it from there or else take a new button.
This does sound like a cache issue, because nowhere in the app does it say "Punch" anymore.
Command-Shift-K to clean the project hopefully fixes that.
If that doesn't work, then search the entire workspace for instances where you used the word "punch".
Try this!!!
override func viewWillAppear(_ animated: Bool) {
// other code
// end of method
// Change the text of your button
}

Swift - Push to ViewController from UIButton in CollectionViewCell

I am trying to make my button, when tapped, to push to a new View Controller. I've tried many different ways but it won't trigger the function that I have it linked to. I also checked the 3D stack view of my layers and the button is on top and clickable, even when I check the background color, it's not being covered by anything else.
Does anyone have any ideas to what I am doing wrong?
For now I am trying to make the button print out the sentence in the console, however whenever I press it, the string doesn't pop up, so I haven't bothered to connect it to the view controller yet.
Also, I am coding this app without storyboards.
Here is my code below.
It is under the MainPageCell class declared as a UICollectionViewCell
private let playButton: UIButton = {
let button = UIButton()
button.setTitle("", for: .normal)
button.backgroundColor = .clear
button.translatesAutoresizingMaskIntoConstraints = false
button.addTarget(self, action: #selector(MainPageCell.buttonTapped), for: .touchUpInside)
return button
}()
#objc func buttonTapped() {
print("I PRESSED THE BUTTON")
}
This line is wrong:
button.addTarget(self, action: #selector(MainPageCell.buttonTapped), for: .touchUpInside)
You cannot assign self as the action target in a property declaration initializer, because the instance designated by self does not exist yet. There is no error or warning (I regard that as a bug), but the action method is never called.
Move that assignment elsewhere and rewrite it, like this:
self.playButton.addTarget(self, action: #selector(MainPageCell.buttonTapped), for: .touchUpInside)
Maybe try defining your button action under the UIView Class, I've had a problem like that before, only worked when i linked it to the View Class, Good luck

Swift: Change colour of button when tapped

I'm new to Swift and I'm trying to change the button colour on tap. When the button is tapped, it should change colour and when released it should go back to the original button colour.
An example of this is the calculator. When you tap a button, it changes from light grey to dark grey and when the user removes their finger off the button, it goes back to the original light grey colour. How do I go about doing that?
So far, I've only got this..
#IBAction func changeButtonColourOnTouch(sender: UIButton) {
zeroButton.backgroundColor = UIColor.blueColor()
}
The above code changes the button colour to blue but stays blue.
The problem is, after releasing the button, you should return the color to the original state.
You can link direct from storyboard, in the action TouchUpInside (release) and TouchDown (press) , to change the button color to the correct state in each event.
Or you can add a Target in the button by code, linking to the functions, as the code bellow shows it.
zeroButton.addTarget(self, action: Selector("holdRelease:"), forControlEvents: UIControlEvents.TouchUpInside);
zeroButton.addTarget(self, action: Selector("HoldDown:"), forControlEvents: UIControlEvents.TouchDown)
//target functions
func HoldDown(sender:UIButton)
{
zeroButton.backgroundColor = UIColor.blueColor()
}
func holdRelease(sender:UIButton)
{
zeroButton.backgroundColor = UIColor.whiteColor()
}
Code adapted by the present in the link UIButton with hold down action and release action
The checked answer above works, but if the user holds down on the button, then drags out, the background color won't return to normal. It's a tiny UI bug, but a simple fix. This includes the code of the checked answer.
zeroButton.addTarget(self, action: #selector(holdRelease), for: .touchUpInside);
zeroButton.addTarget(self, action: #selector(heldDown), for: .touchDown)
zeroButton.addTarget(self, action: #selector(buttonHeldAndReleased), for: .touchDragExit)
//target functions
#objc func heldDown()
{
zeroButton.backgroundColor = .blue
}
#objc func holdRelease()
{
zeroButton.backgroundColor = .white
}
#objc func buttonHeldAndReleased(){
zeroButton.backgroundColor = .blue
}
you could also use a tap gesture and change the color of the button as the user is tapping on the button
you could see apple documentation regarding UIGestureRecognizer in here
it is a little bit advanced, but you will learn a lot from it.
You can also use setbackgroundImageForState to define color image as button background for all UIControlState you are interested in e.g. Normal, Highlighted, Disabled, Selected.
let cx = UIGraphicsGetCurrentContext()
let color = UIColor.redColor()
let state = UIControlState.Selected
UIGraphicsBeginImageContext(CGSize(width:1, height:1))
CGContextSetFillColorWithColor(cx, color.CGColor)
CGContextFillRect(cx, CGRect(x:0, y:0, width:1, height:1))
let colorImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
self.zeroButton.setBackgroundImage(colorImage, forState: state)
Now color changes automatically and you don't have to handle it manually.
If you want that for a programmatically defined button, just declare the button of type system during its initialisation:
let button = UIButton(type: .system)

Hide cursor on UITextView - Swift

I have an app that have user feedback feature. I have done the view as shown in the image.
Feedback view that I made
Message area is using UITextView.
What I want to do now is when user finished editing the textView, then they click other places such as the star rating or any area besides textview, it will hide the cursor on the textview but it will keep the written text at the same time.
Can anyone help me with this? Thank you.
You can make the tint color transparent to hide the cursor.
textView.tintColor = UIColor.clearColor()
In Swift 3:
textView.tintColor = UIColor.clear
Update for Swift 3.x:
textField.tintColor = .clear
Try this:
1) Add a tap gesture recogniser to your view in an appropriate place (viewDidLoad for example)
let tapRecognizer = UITapGestureRecognizer(target: self, action: "hideKeyboard")
view.addGestureRecognizer(tapRecognizer)
2) Then you need to add hideKeyboard method. Example implementation
func hideKeyboard() {
view.endEditing(true)
}
That should do it :)

How to prevent uibutton alpha from going to zero when button tapped in Swift?

The alpha of a UIbutton goes to zero, and it becomes transparent when tapped. Ive added this IBAction
#IBAction func btnTapped(sender: UIButton) {
sender.highlighted = false
//...
}
and the UIButton still gets transparent when touched. How to prevent that?
I wrestled with this problem and finally fixed it by changing the button type from System to Custom.
Did you try something like:
yourButtonClass.setTitleColor(UIColor.blackColor(), forState: .Highlighted)

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