In iOS 6, I have a UITableView, with pull to refresh enabled. In the top cell, I have a couple of customs controls which the user can interactive by dragging a circular slider (see this example). See screenshot...
The control need a tag and dragging of the slider indicators need to be dragged but they can be tricky to grab as the hit seems to often be on the cell background, causing the table dragging to kick in.
I would like to disable the default scrolling of table if the tap event happens anywhere on those controls. Two options I can think off:
disable table dragging for any event within that top cell
make sure the controls handles events on an larger area, in particular in parts where they have a transparent background
Any suggestions on how to achieve either of these?
Thanks!
I used to subclass of UIControl and override these functions:
override func continueTracking(_ touch: UITouch, with event: UIEvent?) -> Bool { }
override func endTracking(_ touch: UITouch?, with event: UIEvent?) {}
override func beginTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {}
It works fine for me of this circle slider style.
If still doesn't work you can try to turn on/off your tableView scrollable in the methods above.
tableView.isScrollEnabled = false / true
Related
I have a layout with a UIView at the top of the page and, right below it, I have a UITableView.
What I am wanting to do is to transfer the gesture interactions on the UIView to the UITableView, so when the user makes a drag up/down on the UIView, the UITableView scrolls vertically.
I tried the following code
tableView.gestureRecognizers?.forEach { uiView.addGestureRecognizer($0) }
but it removed the gestureRecognizers from the UITableView somehow :/
Obs.: the UIView cannot be a Header of the UIScrollView
That's Tricky
What is problem ?
Your top view is not allowed to pass through view behind it...
What would be possible solutions
pass all touches to view behind it (Seems to not possible or very tough practically )
Tell window to ignore touches on top view (Easy one)
Second option is better and easy.
So What you need to do is create subclass of UIView and override
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView?
and return nil if you found same view on hitTest action
Here Tested and working example
class PassThroughME : UIView {
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
return super.hitTest(point, with: event) == self ? nil : self
}
}
That's it now use PassThroughME either by adding class to your view in storyboard or programmatically whatever way you have added your view
Check image i have black color view with 0.7 alpha on top still i am able to scroll
Hope it is helpful
I am working on a tiny project where I want to use the 3D touch screen pressure capabilities (e.g. touch.force).
Right now I can measure force in my ViewController and it is behaving like I want it:
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
if let touch = touches.first {
if traitCollection.forceTouchCapability == UIForceTouchCapability.available {
// 3D Touch capable
let force = touch.force
print("Force: " + force.description)
}
}
}
I have one UIImageView that presents a picture. I also use an custom UICollectionView as overlay, which contains transparent cells and colored cells. What I am trying to achieve is to measure both force, and be able to remove the color from the cells when they are pressed, but I am failing to do both. I can either measure force, or change the color of a cell in the UICollectionView, but not both.
The solution as I see it is to forward touches from the UICollectionView to the next view in the hierarchy. But another solution could be to measure both force and register taps on cells from within the custom UICollectionView.
My question is, is either of my proposed solutions any good? And if so, how do I achieve them?
Apparently the override func touches... methods are part of UIView, not neccesarily UIViewControllers. This means that implementing the touchesMoved and other methods into my custom UICollectionView is perfectly possible and it solved my problem of handling touches and taps at the same time.
I have a custom button and it's added to a static cell. Somehow whenever I tap the button, it doesn't react immediately like when the button is added to a plain normal view.
When tapped, it registers the tap right away but the background color has a slight delay before changing.
To change the color I have the following code in my subclass of UIButton:
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
super.touchesBegan(touches, withEvent: event)
border.fillColor = .redColor() // border is a CAShapeLayer
print("began") // This prints right when the button is clicked
}
This button is added in a subclass of UITableViewCell and the button is reacting, except changing the color has a delay. How can I fix this?
Answer (by Jelly):
The answer of Jelly helped me a lot and made the button react a bit better. Knowing what the problem is also made it easier to research the problem and found out to make the button react just as it would in a normal view I have to disable both delaysContentTouches in the table view and it's subviews:
tableView.delaysContentTouches = false
tableView.subviews.forEach { ($0 as? UIScrollView)?.delaysContentTouches = false }
Set delaysContentTouches = false on your tableView.
On top of my UICollectionViewCells in my UICollectionView I've overlaid a UIButton that intercepts touches so I can respond to touch events more granularly. The issue is that now the collection view no longer gets didSelectItemAtIndexPath messages. (For obvious reasons... the button has absorbed the touch and isn't signaling to the collection view that the item was selected.)
Is there a way to signal to the collection view that the cell was selected? I've seen similar questions but none seem to give a convincing answer.
You can override the pointInside:withEvent: message on UIView [and subclasses] and return false to continue propagating the touch event.
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIView_Class/#//apple_ref/occ/instm/UIView/pointInside:withEvent:
class PassThroughButton: UIButton {
override func pointInside(point: CGPoint, withEvent event: UIEvent?) -> Bool {
// do something
// then continue event propigation
return false
}
}
I have a custom subclass of UIView, designed in IB that contains a few labels and a button.
There is an action for touchUpInside event on the button and the target is the custom view.
I am attaching this custom view to a self.tableView.tableHeaderView for a tableview in my UI.
The strange thing is this custom view is not responding to touches. I can see it nicely with all the labels and the button in side the table view, that means the table view handles and shows it correctly, however it is not responding to touches.
I checked the whole view hierarchy and all the views involved have userInteractionEnabled as YES.
If i drag some other controls into that custom view for example a switch, segmented control..they do not respond as well. It is like these controls in custom view are not registering touches.
It doesn't make any sense. I am out of ideas. Can you help to allow the touch event on the button to arrive to its parent view?
What is a "headerTableView"? Do you mean a UITableViewHeaderFooterView? Have you tried setting userInteractionEnabled on the root UITableViewHeaderFooterView?
This is a hack that will detect a button touch and trigger touchUpInside programmatically:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?)
{
super.touchesBegan(touches, with: event)
if let touch = touches.first, button.bounds.contains(touch.location(in: button)) {
button.sendActions(for: UIControl.Event.touchUpInside)
}
}
I don’t know what your real problem is because that button should work without this.