I have an app with two tab views, view 1 and view 2. When I switch to view 2, I need to do some things in view 1, before it switches to view 2. As part of this, I have the following code.
$scope.$on('$ionicView.beforeLeave', (event) => {
const stateName = $ionicHistory.currentStateName()
console.log('beforeLeave', stateName)
})
When I switch to view 2, I expect the console.log to print view 1 as the stateName, however it prints view 2, which is counterintuitive because I would expect to return the state before I leave the view ie beforeLeave.
Is there perhaps some other event I need to listen to?
So it looks like the event $stateChangeStart does the trick that I am looking for, and what I would expect beforeLeave to do.
Related
I am using a SplitViewController and on the detail page (which is set to "defines context"), the user can select "+" in the navbar and I present the next view controller "modally over current context" using a segue. On that view controller I am using Eureka and one of the rows I want to use is PushRow. The issue I am running into is when I select an option on the PushRow, the view (table of options to choose that Eureka generated) never closes. The list of options stays full screen. I can see that PushRow.onChange is called and it has the correct value. For some reason that topmost view will not close.
I dug deeper and it seems like I need to modify the PushRow presentationMode to be "presentModally" since I am presenting it from a modal. However, I am not sure what to put for the controllerProvider. Is this the right path? If so, what would the correct syntax be? I also tried doing a reload in the onChange but that didn't make a difference.
private func getGroupPushRow() -> PushRow<String> {
return PushRow<String>() {
$0.title = "Group"
$0.selectorTitle = "What is the Group?"
$0.noValueDisplayText = "Select a Group..."
$0.options = self.getGroups()
$0.presentationMode = PresentationMode.presentModally(controllerProvider: ControllerProvider<VCType>, onDismiss: { () in
})
$0.onChange({ (row) in
print("in onchange \(row.value)")
// row.reload()
// self.tableView.reloadData()
})
}
}
I eventually figured out a solution so I'm posting it here to hopefully help out somebody else. Going off of the example above, replace presentationMode & onChange with this code. Note that if you are using another object in your PushRow besides String, then the type in PushSelectorCell should be that type instead.
$0.presentationMode = PresentationMode.presentModally(
controllerProvider: ControllerProvider.callback {
return SelectorViewController<SelectorRow<PushSelectorCell<String>>> { _ in }
},
onDismiss: { vc in
vc.dismiss(animated: true)
})
$0.onChange({ (row) in
row.reload()
})
I'm having a bit of a brain fart in Swift and I know this code could be written better. Basically what it is, I have two images and I check if a value is over 3 to show an image and hide the other.
currently I have it like this
let greaterThanThree = value > 3
image1.isHidden = greaterThanThree
image2.isHidden = !greaterThanThree
But I feel like there is a more elegant way to write this.
I'd write it like this:
image1.isHidden = value > 3
image2.isHidden = !image1.isHidden
Anything shorter than that is just code golfing.
There seems to be a rule here that exactly one of these two views should be visible at all times. If so, I'd create, as part of my view controller's viewDidLoad, an instance of this struct:
struct AlternateViews {
let views : [UIView]
init(_ v1:UIView, _ v2:UIView) {
views = [v1,v2]
}
func hide(first:Bool) {
views[0].isHidden = first
views[1].isHidden = !first
}
}
let alternateViews = AlternateViews(image1, image2)
Okay, that's a lot of work to set up initially, but the result is that later you can just say
self.alternateViews.hide(first: value > 3)
The struct is acting as a tiny state machine, making sure that your view controller's views remain in a coherent state. This technique of moving the rules for state into utility structs attached to your view controller is recommended in a WWDC 2016 video and I've been making a lot of use of it ever since.
If you have more pairs of alternating views, just make and maintain more instances of the struct.
(If the rule that I've assumed is not quite the real rule, make a struct that does express the real rule.)
You can do this:
(image1.isHidden, image2.isHidden) = (value > 3) ? (true, false) : (false, true)
Basically if the value is greater than 3, the first image will be hidden and the second one won't. Otherwise, the second image will be hidden and the first one will not.
My page contains 3 tabs, if i forward to next page from tab3 and then coming back from that page using $ionicHistory.goBack() it redirects to tab1. how to make it redirects to tab3 itself
function sample($scope,$ionicHistory){
$ionicHistory.goBack();
};
}
I'm not sure it's possible to do that just through $state. I'm new to Ionic myself as I had my first peek back in December (2016). However, I happened to have this exact scenario. This is how I solved it.
In my case, I was not using tabs. Instead, I had three different DIVs that were visible depending on the "tab number". When initializing the view, I set it to "1" and used the property to control what code is executed.
I'm guessing that the control you're using has a property like that to identify and set the particular tab you need, as this is the most likely way to change tabs on tab-click. Consider putting the value of that property "tab #" into the appropriate service used by the controller. This is a stripped-down version of actual code in one of my services defined via Factory.
YourService.js:
// controllers are instances. When navigating away, state is lost. This
// tracks the tab we wish to view when we load the home page.
var activeHomePageTab = 1;
var service = {
getActiveTab: getActiveTab,
setActiveTab: setActiveTab,
...
};
return service;
////////////////
function getActiveTab() { return activeHomePageTab; }
function setActiveTab(num) { activeHomePageTab = num; }
...
Here, the functions are private. In your controller, when you set your tab, also set this property. As a singleton, this will remain in effect as long as your application is running.
Next, in your init() routine, when the controller is loaded, check for this property and set the tab if it is defined:
function init() {
var tab = YourService.getActiveTab();
if (tab !== undefined) {
setTab(tab);
} else {
setTab(1)
}
...
}
Of course, there are other ways - maybe using Value or a property on a Constant object.
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
Where, and how do I clear out the input date on a view....
E.g. when the data is saved, and I access my page from the menu, the old data is still displayed in the input boxes.
I've tried the onInit() function but that only fires the first time into the view.
The navto call is in the BaseController which calls the defaultTimes page (view/controller).
onNavToDefaultTimes : function(oEvent) {
this.getRouter().navTo("defaultTimes");
}
My clear code was in the _onRouteMatched function of detaultTimes.....
_onRouteMatched : function(oEvent) {
var view = this.getView();
view.byId("shopInput").setValue("");
view.byId("effectiveDateFrom").setValue("");
view.byId("shop24Hrs").setSelected(false);
view.byId("shopClosed").setSelected(false);
},
The problem is though, _onRouteMatched is also callled from navBack of the page following default times. And I don't want to clear the fields in this case.
How do I implement the clear from the onNavToDefaultTimes function of the base Controller only?
Can you give an example.
Let's say the name of the view in which your input field is created is test.js, then whenever you are navigating to the view or navigating from the view, you can use invalidate view like below
sap.ui.getCore().byId("test").invalidate();
this makes the view to be rendered again when you are coming back to the view and onBeforeRendering() is triggered
You can choose one of the following options, and put one of them, after the code to save is executed:
Option 1:
var yourInput = this.getView().byId("yourInputID");
yourInput.setValue("");
Options 2 (Try someone):
var yourInput = this.getView().byId("yourInputID");
yourInput.unbindValue();
yourInput.unbindElement();
yourInput.unbindObject();
Or put the code in the following method, which is executed every time the view is displayed:
onAfterRendering: function(){
//Option choosed
}