I've got five radio buttons, and selecting one should deselect the others.
I've been over a lot of the questions here about radio buttons in Swift, but they're either for iOS or outdated versions of Swift, because Xcode isn't offering me options like ".isSelected". I've got ".isEnabled" but clearly semantics matter here, because "enabled" isn't the same thing as "selected" and it shows.
Writing my code as a series of "if-else" statements along these lines:
func disableUnselectedButtons() {
if Button2.isEnabled == true {
Button1.isEnabled = false
Button3.isEnabled = false
Button4.isEnabled = false
Button5.isEnabled = false
}
}
results in a situation where I can select all five buttons, and can't DEselect any of them after another has been selected. I've tried variations of .on/.off as well, and can't find the right one for this situation.
It's also clumsy as heck to write a method with five if-else statements along those lines. So there's that.
What's the best way to go about implementing this?
If your radio buttons have the same superview and have the same action then they should work as expected.
To set the same action for each of your radio buttons you can do one of the following.
If you are using Storyboards, open both storyboard and related NSViewController swift file. Ctrl-drag your first radio button to the swift file. Then do the same for each of the other radio buttons ensuring you are dragging onto the function generated from the first Ctrl-drag.
If you are creating the radio buttons in code then set the action parameter in the init for each radio button to be the same.
Another way to approach this is to represent the buttons as a Set and then it's easy to iterate through them and configure their state. The below code actually allows for allowing multiple selections to support a scenario that wants to "select three of the six options".
let allButtons = Set(1...5). //or however many you want
func selectActiveButtons(_ activeButtons: Set<Int>, from allButtons: Set<Int>){
let inactive = allButtons.subtracting(activeButtons)
setButtonState(forButtons: inactive, isSelected: false)
setButtonState(forButtons: activeButtons, isSelected: true)
}
func setButtonState(forButtons buttons: Set<Int>, isSelected: Bool) {
buttons.forEach{
//remove below line and replace with code to update buttons in UI
print("Button \($0): \(isSelected ? "Selected" : "Unselected")")
}
}
// select buttons 1 & 3.
//If wanting a "classic" radio button group just use one value in the arrayLiteral.
selectActiveButtons(Set(arrayLiteral: 1,3), from: allButtons)
Related
I have a couple of UIKit pop-up menu buttons with identical menu items on the same screen in a Swift app. The buttons are built by calling a function that uses an array of strings to create the list of menu items.
The problem is that depending on the button's vertical position on the screen, the menu items may appear in the order specified by the function, or reversed. If the button is in the upper half of the screen, the menu items are listed in the correct order. If the button is in the lower half of the screen the menu items are listed in reverse order.
I would prefer the menu items to appear in the same order regardless of the button's position on the screen. I could check the button location and have the menu creation function reverse the order, but that seems kind of clunky. I am hoping there's a cleaner way to override this behaviour.
The code and array used to create the button menus:
let buttonMenuItems = ["Spring","Summer","Autumn","Winter"]
func createAttributeMenu(menuNumber: Int)->UIMenu {
var menuActions: [UIAction] = []
for attribute in buttonMenuItems {
let item = UIAction(title: attribute) { action in
self.updateMenu(menuID: menuNumber, selected: attribute)
}
menuActions.append(item)
}
return UIMenu(title: "", children: menuActions)
}
The result is this:
Versions I'm using now in testing: Xcode 14.1, iOS 16.1, but I have seen this behaviour on earlier versions as well. (back to iOS 14.x)
Starting with iOS 16, there is a .preferredMenuElementOrder property that can be set on the button:
case automatic
A constant that allows the system to choose an ordering strategy according to the current context.
case priority
A constant that displays menu elements according to their priority.
case fixed
A constant that displays menu elements in a fixed order.
Best I can tell (as with many Apple definitions), there is no difference between .automatic and .priority.
From the .priority docs page:
Discussion
This ordering strategy displays the first menu element in the UIMenu closest to the location of the user interaction.
So, we get "reversed" order based on the position of the menu relative to the button.
To keep your defined order:
buttonNearTop.menu = createAttributeMenu(menuNumber: 1)
buttonNearBottom.menu = createAttributeMenu(menuNumber: 2)
if #available(iOS 16.0, *) {
buttonNearBottom.preferredMenuElementOrder = .fixed
buttonNearTop.preferredMenuElementOrder = .fixed
} else {
// out of luck... you get Apple's "priority" ordering
}
I have a button that responds to various mouse clicks (regular click, right click, control+click, option+click, command+click...) to show different popup menus. Since it would be annoying for VoiceOver users to use actual physical mouse, I would like to map those to different VoiceOver actions.
However, I'm not getting the results I expected. Could someone help me to understand better what I'm missing? Here is what I discovered so far.
If I subclass NSButton and override the following functions, they work fine. Except there's one odd thing. If I press vo+command+space to bring up the list of available actions, VoiceOver says Action 1 instead of Show Menu.
override func accessibilityPerformPress() -> Bool {
print("Pressed!")
return true
}
override func accessibilityPerformShowAlternateUI() -> Bool {
print("Show Alternate UI")
return true
}
override func accessibilityPerformShowMenu() -> Bool {
print("Show Menu")
return true
}
In the same NSButton subclass, if I also override accessibilityCustomActions function, "Do Something" never comes up in the list of available actions when I press vo+command+space.
override func accessibilityCustomActions() -> [NSAccessibilityCustomAction]? {
let custom = NSAccessibilityCustomAction(name: "Do Something", target: self, selector: #selector(doSomething))
return [custom]
}
#objc func doSomething() -> Bool {
print("Done something.")
return true
}
If I subclass NSView instead of NSButton, and override the same functions from #1, everything works fine. Unlike first case, even VoiceOver correctly says "Show Menu" for the action from accessibilityPerformShowMenu instead of "Action 1".
in the same NSView subclass, if I override accessibilityCustomActions along with accessibilityPerformPress, accessibilityPerformShowMenu, or accessibilityPerformShowAlternateUI, "Do Something" doesn't come up in the action list.
However, "Do Something" does come up in the action list if I just override accessibilityCustomActions by itself without accessibilityPerformPress, accessibilityPerformShowMenu, and accessibilityPerformShowAlternateUI.
I tried creating another action with the name "Press" that does the same thing when pressing vo+space, and including in the return value of accessibilityCustomActions. However, Vo+space did not trigger the action. Instead, I had to press vo+command+space, and then select "Press". I guess the action just has the name "Press", but it's not actually connected to vo+space. I'm not sure how I can actually make that particular custom action to respond to vo+space.
I would appreciate if someone could help me to implement accessibilityCustomActions as well as accessibilityPerformPress, accessibilityPerformShowMenu, and accessibilityPerformShowAlternateUI together into NSButton.
Thanks so much!
The problem is that you are overriding these AX methods on the NSButton, not the NSButtonCell. For nearly everything to do with accessibility in NSControls, you will want to deal with the NSCell in question. If you use the custom action code you've written above and stick it in a subclass of NSButtonCell used by your button, then it will work.
Dear SAPUI5 developers,
I have a sap.m.IconTabBar and I set the active tab by the code when the user switch between pages. I used the following code:
sap.ui.getCore().byId(this.createId("iconTabBar")).setSelectedKey("1");
The problem is that it switch the selected tab correctly to the first tab. But it does not show the blue line under the tab that shows it is selected.
Please look at the following images:
What shows when I select the first tab by code:
But what it shows when I press the tab by the mouse it shows a blue line under the icon like the following:
As #Ash said in the comments you need to call fireSelect but this works just if user the second tab at first. If the user is on the first tab and switches between the pages then fireSelect does not act properly. Thus you need to select the second tab at first then it will works almost all times.
sap.ui.getCore().byId(this.createId("iconTabBar")).setSelectedKey("2");
sap.ui.getCore().byId(this.createId("iconTabBar")).setSelectedKey("1");
sap.ui.getCore().byId(this.createId("iconTabBar")).fireSelect();
Ok I had a look into the IconTabBar source Code and theres something I dont really get why but here is how it proceeds :
when you call IconTabBar.setSelectedKey(key), it calls IconTabHeader.setSelectedKey(key)
then internally the IconTabBarHeader calls setSelectedItem(item, true)
the 'true' here is important, the parameter is named 'bAPIchange' in the setSelectedItem function, and it is used as condition for the fireSelect() :
if (!bAPIchange) {
// fire event on iconTabBar
if (bIsParentIconTabBar) {
oParent.fireSelect({
selectedItem: this.oSelectedItem,
selectedKey: sSelectedKey,
item: this.oSelectedItem,
key: sSelectedKey
});
} else {
// fire event on header
this.fireSelect({
selectedItem: this.oSelectedItem,
selectedKey: sSelectedKey,
item: this.oSelectedItem,
key: sSelectedKey
});
}
}
Which explains why the event is not fired in your case
I want to only highlight a data point when the finger is on the chart, as soon as it lifts off the screen I want to call, or simple deselect the highlight.
func chartValueNothingSelected(chartView: ChartViewBase) {
print("Nothing Selected")
markerView.hidden = true
}
I've tried to override the touch ended but haven't gotten it to work.
You can turn off highlighting any bars/data all together using the highlightEnabled property.
Example of this is:
barChartView.data?.highlightEnabled = false
If you still want to be able to highlight values, but want them to automatically deselect after the touch has ended, I also found another function highlightValues(highs: [ChartHighlight]?) which says in the documentation..
Provide null or an empty array to undo all highlighting.
Call this when you want to deselect all the values and I believe this will work. Example of this could be:
let emptyVals = [ChartHighlight]()
barChartView.highlightValues(emptyVals)
Ref:
Charts Docs: highlightValues documentation
If you don't have to do anything with the tapped data you can use:
barChartView.data?.highlightEnabled = false
If you want to use the tapped data point without displaying the highlight lines, you can use the selection delegate (don't forget to add ChartViewDelegate to your class):
yourChartView.delegate = self // setup the delegate
Add delegate function:
func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight) {
// do something with the selected data entry here
yourChartView.highlightValue(nil) // deselect selected data point
}
I have a UITableView, which I want to put into an editing state if certain conditions are met. The primary way to toggling edit is through an edit button.
So the view elements I have are
let tableView = UITableView()
let editButton = UIButton()
And whether the tableView should be in editing mode is fed from:
let editing = BehaviorSubject(value: false)
Which will be hooked up to the tableView using something like:
editing.subscribeNext { isEditing in
tableView.setEditing(isEditing, animated: true)
}
When the edit button is tapped, I want that to push a new value to editing, that is the negation of the most recent value sent to editing. The most recently value may have been set by a tap on editButton, or it may have come from somewhere else.
I don't understand how to combine the stream for the button press with the stream for editing in such a way that allows this without an infinite loop e.g.
Obervable.combineLatest(editButton.rx_tap.asObservable(), editing) { _, isEditing in
editing.onNext(!isEditing)
}
I'm aware that the tableView has an editing property, but I don't want to rely on that as I am looking for a more general solution that I can re-use elsewhere. I'm also not looking to track the value of isEditing in an instance var, or even as a Variable(), as I am looking for a stateless, stream based solution (if this is at all possible).
Thank you!
With some help from the RxSwift GitHub issues forum I've now worked it out :). The key was withLatestFrom. I've included an example of this below in case it will help anyone else. editButton is the primary way to trigger editing mode on or off, and I've included an event sent via tableView.rx_itemSelected as an additional input example (in this case, I want editing to end any time an item is selected).
let isEditing = BehaviorSubject(value: false)
let tableView = UITableView()
let editButton = UIButton()
tableView.rx_itemSelected
.map { _ in false }
.bindTo(isEditing)
editButton.rx_tap.withLatestFrom(isEditing)
.map { !$0 }
.bindTo(isEditing)
isEditing.subscribeNext { editing in
tableView.setEditing(editing, animated: true)
}
Note: This solution sends .Next(false) to isEditing every time an item is selected, even if the table isn't currently in editing mode. If you feel this is a bad thing, and want to filter rx_itemSelected to only send .Next(false) if the table is actually in editing mode, you could probably do this using a combination of withLatestFrom and filter.
What if you define editing as a Variable instead of a BehaviourSubject. A Variable cannot error out which makes sense in this case. The declaration would look like this:
let editing = Variable(value: false)
You could subscribe to a button tap and change the value of editing to the negated current one:
editButton.rx_tap.asObservable().subscribeNext { editing.value = !editing.value }
With changing the value property of editing this method is called
editing.subscribeNext { isEditing in
tableView.setEditing(isEditing, animated: true)
}
All of this is not tested, but might lead you in the right direction for the right solution.