I tried to disable animation in UITests with the following code:
let app = XCUIApplication()
app.launchEnvironment = ["DISABLE_ANIMATIONS": "1"]
I also tried:
UIView.setAnimationsEnabled(false)
But it doesn't disable animation when I run UITests on simulator.
Is it because I'm using SwiftUI ?
The animation I want to disable is a view transition from one SwiftUI View to another one. Here is how I coded the transition:
NavigationLink(destination: MapView(), isActive: $viewModel.isDataLoaded) {
EmptyView()
}
Is there another way to disable animation in UITests when using SwiftUI ?
It is needed to be done explicitly (by-code) in main application, because UITests run in different process, ie. it should be like
struct YourApp: App {
init() {
let env = ProcessInfo.processInfo.environment
if env["DISABLE_ANIMATIONS"] == "1" { // << here !!
UIView.setAnimationsEnabled(false)
}
}
var body: some Scene {
// ... scene here
}
}
and then it can be used
let app = XCUIApplication()
app.launchEnvironment = ["DISABLE_ANIMATIONS": "1"]
Tested with Xcode 13.3 / iOS 15.4
I want to hide listview scrollbar in my xamarin andorid and xamarin ios application's. I have searched many post's but only few post's are having the helpful that to not clear. Please suggest any idea of hide scrollbar in listview.
Here is what I did:
Android custom renderer:
[assembly: ExportRenderer(typeof(CustomListView),typeof(CustomListViewRenderer))]
namespace ImageList.Droid
{
public class CustomListViewRenderer : ListViewRenderer
{
protected override void OnElementChanged(ElementChangedEventArgs<ListView> e)
{
base.OnElementChanged(e);
if(Control != null)
{
Control.VerticalScrollBarEnabled = false;
}
}
}
}
iOS custom renderer:
[assembly: ExportRenderer(typeof(CustomListView), typeof(CustomListViewRenderer))]
namespace ImageList.iOS
{
public class CustomListViewRenderer : ListViewRenderer
{
protected override void OnElementChanged(ElementChangedEventArgs<ListView> e)
{
base.OnElementChanged(e);
if (Control != null)
{
Control.ShowsVerticalScrollIndicator = false;
}
}
}
}
Remember: We need to use the Custom ListView instead of the native ListView in the PCL Forms
Update: Now from Xamarin.Forms version 3.5.0, we can use VerticalScrollBarVisibility, HorizontalScrollBarVisibility properties to handle ListView ScrollBarVisibility.
You can also find full source code and document from http://bsubramanyamraju.blogspot.com/2019/03/hide-listview-scrollbar-in-xamarinforms.html
Custom renders for the solution here, check official documents for that
https://developer.xamarin.com/guides/xamarin-forms/application-fundamentals/custom-renderer/listview/
Android:
ListView.VericalScrollbarEnabled = false;
iOS:
UIScrollView.ShowsVerticalScrollIndicator = false;
I have a Prism based Xamarin Forms app that contains an edit page that is wrapped in a Navigation page so there is a back button at top left on both Android and iOS. To avoid the user accidentally losing an edit in progress by accidentally clicking the back button (in particular on Android) we want to prompt them to confirm that they definitely want to cancel.
Thing is, this seems like something that is not baked in to Xamarin forms. You can override OnBackButtonPressed in a navigation page, but that only gets called for the hardware/software back button on Android. There are articles detailing techniques to intercept the actual arrow button at the top left on Android (involving overriding OnOptionsItemSelected in the Android MainActivity), but on iOS I'm not sure it is even possible.
So I can't help but wonder if I am going about this the wrong way? Should I not be intercepting the top left / hardware / software back button in this way? Seems like a pretty common thing to do (e.g. press back when editing a new contact in the android built in Contacts app and you get a prompt) but it really feels like I am fighting the system here somehow.
There are previous questions around this, most relevant appears to be How to intercept Navigation Bar Back Button Clicked in Xamarin Forms? - but I am looking for some broad brush suggestions for an approach here. My objective is to show the user a page with the <- arrow at top left for Android, "Cancel" for iOS but I would like to get some views about the best way to go about it that does not involve me fighting against prism / navigation pages / xamarin forms and (where possible) not breaking the various "best practices" on Android and iOS.
After going down the same path as you and being told not to prevent users from going back, I decided on showing an alert after they tap the back button (within ContentPage.OnDisappearing()) that says something like Would you like to save your work?.
If you go with this approach, be sure to use Application.MainPage.DisplayAlert() instead of just this.DisplayAlert() since your ContentPage might not be visible at that point.
Here is how I currently handle saving work when they click the back button (I consolidated a good bit of code and changed some things):
protected override async void OnDisappearing() {
base.OnDisappearing();
// At this point the page is gone or is disappearing, but all properties are still available
#region Auto-save Check and Execution
/*
* Checks to see if any edits have been made and if a save is not in progress, if both are true, it asks if they want to save, if yes, it checks for validation errors.
* If it finds them, it marks it as such in the model before saving the model to the DB and showing an alert stating what was done
*/
if(!_viewModel.WorkIsEdited || _viewModel.SaveInProgress) { //WorkIsEdited changes if they enter/change data or focus on certain elements such as a Picker
return;
}
if(!await Application.Current.MainPage.DisplayAlert("ALERT", "You have unsaved work! Would you like to save now?", "Yes", "No")) {
return;
}
if(await _viewModel.SaveClaimErrorsOrNotAsync()) { //The return value is whether validation succeeds or not, but it gets saved either way
App.SuccessToastConfig.Message = "Work saved successfully. Try saving it yourself next time!";
UserDialogs.Instance.Toast(App.SuccessToastConfig);
} else if(await Application.Current.MainPage.DisplayAlert("ERROR", "Work saved successfully but errors were detected. Tap the button to go back to your work.", "To Work Entry", "OK")) {
await Task.Delay(200); //BUG: On Android, the alert above could still be displayed when the page below is pushed, which prevents the page from displaying //BUG: On iOS 10+ currently the alerts are not fully removed from the view hierarchy when execution returns (a fix is in the works)
await Application.Current.MainPage.Navigation.PushAsync(new WorkPage(_viewModel.SavedWork));
}
#endregion
}
What you ask for is not possible. The back button tap cannot be canceled on iOS even in native apps. You can do some other tricks like having a custom 'back' button, but in general you shouldn't do that - you should instead have a modal dialog with the Done and Cancel buttons (or something similar).
If you use xamarin forms that code it is work.
CrossPlatform source
public class CoolContentPage : ContentPage
{
public Action CustomBackButtonAction { get; set; }
public static readonly BindableProperty EnableBackButtonOverrideProperty =
BindableProperty.Create(nameof(EnableBackButtonOverride), typeof(bool), typeof(CoolContentPage), false);
public bool EnableBackButtonOverride{
get { return (bool)GetValue(EnableBackButtonOverrideProperty); }
set { SetValue(EnableBackButtonOverrideProperty, value); }
}
}
}
Android source
public override bool OnOptionsItemSelected(IMenuItem item)
{
if (item.ItemId == 16908332)
{
var currentpage = (CoolContentPage)
Xamarin.Forms.Application.
Current.MainPage.Navigation.
NavigationStack.LastOrDefault();
if (currentpage?.CustomBackButtonAction != null)
{
currentpage?.CustomBackButtonAction.Invoke();
return false;
}
return base.OnOptionsItemSelected(item);
}
else
{
return base.OnOptionsItemSelected(item);
}
}
public override void OnBackPressed()
{
var currentpage = (CoolContentPage)
Xamarin.Forms.Application.
Current.MainPage.Navigation.
NavigationStack.LastOrDefault();
if (currentpage?.CustomBackButtonAction != null)
{
currentpage?.CustomBackButtonAction.Invoke();
}
else
{
base.OnBackPressed();
}
}
iOS source
public override void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
if (((CoolContentPage)Element).EnableBackButtonOverride)
{
SetCustomBackButton();
}
}
private void SetCustomBackButton()
{
var backBtnImage = UIImage.FromBundle("iosbackarrow.png");
backBtnImage = backBtnImage.ImageWithRenderingMode
(UIImageRenderingMode.AlwaysTemplate);
var backBtn = new UIButton(UIButtonType.Custom)
{
HorizontalAlignment =
UIControlContentHorizontalAlignment.Left,
TitleEdgeInsets =
new UIEdgeInsets(11.5f, 15f, 10f, 0f),
ImageEdgeInsets =
new UIEdgeInsets(1f, 8f, 0f, 0f)
};
backBtn.SetTitle("Back", UIControlState.Normal);
backBtn.SetTitleColor(UIColor.White, UIControlState.Normal);
backBtn.SetTitleColor(UIColor.LightGray, UIControlState.Highlighted);
backBtn.Font = UIFont.FromName("HelveticaNeue", (nfloat)17);
backBtn.SetImage(backBtnImage, UIControlState.Normal);
backBtn.SizeToFit();
backBtn.TouchDown += (sender, e) =>
{
// Whatever your custom back button click handling
if(((CoolContentPage)Element)?.
CustomBackButtonAction != null)
{
((CoolContentPage)Element)?.
CustomBackButtonAction.Invoke();
}
};
backBtn.Frame = new CGRect(
0,
0,
UIScreen.MainScreen.Bounds.Width / 4,
NavigationController.NavigationBar.Frame.Height);
var btnContainer = new UIView(
new CGRect(0, 0,
backBtn.Frame.Width, backBtn.Frame.Height));
btnContainer.AddSubview(backBtn);
var fixedSpace =
new UIBarButtonItem(UIBarButtonSystemItem.FixedSpace)
{
Width = -16f
};
var backButtonItem = new UIBarButtonItem("",
UIBarButtonItemStyle.Plain, null)
{
CustomView = backBtn
};
NavigationController.TopViewController.NavigationItem.LeftBarButtonItems = new[] { fixedSpace, backButtonItem };
}
using in xamarin forms
public Page2()
{
InitializeComponent();
if (EnableBackButtonOverride)
{
this.CustomBackButtonAction = async () =>
{
var result = await this.DisplayAlert(null, "Go back?" Yes go back", "Nope");
if (result)
{
await Navigation.PopAsync(true);
}
};
}
}
Is there a custom circular activity indicator for UWP/ Win10 apps using Xamarin?
Is there a custom circular activity indicator for UWP/ Win10 apps using Xamarin?
You need to create your own View for UWP's ProgressRing:
Shared Project\MyProgressRing.cs:
public class MyProgressRing:View
{
}
UWP Project\MyProgressRingRenderer.cs:
[assembly:ExportRenderer(typeof(MyProgressRing),typeof(MyProgressRingRenderer))]
namespace CircularActivityDemo.UWP
{
public class MyProgressRingRenderer:ViewRenderer<MyProgressRing,ProgressRing>
{
ProgressRing ring;
protected override void OnElementChanged(ElementChangedEventArgs<MyProgressRing> e)
{
base.OnElementChanged(e);
if (Control == null)
{
ring = new ProgressRing();
ring.IsActive = true;
ring.Visibility = Windows.UI.Xaml.Visibility.Visible;
ring.IsEnabled = true;
SetNativeControl(ring);
}
}
}
}
Notes: I hardcoded the properties of ProgressRing Control. You can create DependencyProperties for your custom ProgressRing control.
I'm developing a mobile application on Xamarin Forms for UWP, Android and IOS on Visual Studio.
I'm currently testing the app on my computer(Windows 10) and my phone (also Windows 10).
I'm using Zxing MobileBarcodeScanner to scan multiple barcodes.
When i press the back button i call the MobileBarcodeScanner.Cancel().
The only thing that it does is to close the camera. It doesn't depose the MobileBarcodeScanner's UI and i didn't found any solution for that.
Can anyone help me or suggest a solution?
Also the Cancel Button and the Flash Button aren't shown to the scanner UI.
Code:
private void showScanner()
{
var scanner = new MobileBarcodeScanner(App.coreDispatcher)
{
UseCustomOverlay = false,
TopText = "Hold camera up to barcode to scan",
BottomText = "Barcode will automatically scan",
CancelButtonText = "Done",
FlashButtonText = "Flash"
}
var opt = new MobileBarcodeScanningOptions { DelayBetweenContinuousScans = 3000 };
scanner.ScanContinuously(opt, HandleScanResult);
}
protected override bool OnBackButtonPressed()
{
scanner.Cancel();
}
private void HandleScanResult(ZXing.Result result)
{
string msg;
if (result != null && !string.IsNullOrEmpty(result.Text)) // Success
{
msg = result.Text;
}
else // Canceled
{
msg = "Scanning Canceled!";
}
}
The only thing that it does is to close the camera. It doesn't depose the MobileBarcodeScanner's UI and i didn't found any solution for that
There is an issue in your code snippets. In the showScanner() method, you have defined a scanner variable, but in OnBackButtonPressed() method, looks like you have used a global variable also called scanner.
Maybe the following way should be correct:
MobileBarcodeScanner scanner;
private void showScanner(){
scanner = new MobileBarcodeScanner(App.coreDispatcher) //Here, remove var
{
......
}
}
protected override bool OnBackButtonPressed()
{
scanner.Cancel();
}
And if you have check the Xamarin.Forms sample
It uses the ZXingScannerPage to host your layout and handle some logics, including Cancel and ToggleTorch etc, see here
Also the Cancel Button and the Flash Button aren't shown to the scanner UI.
Please use Custom Overlay, just set MobileBarcodeScanner.UseCustomOverlay property to true and check the sample code in here
And also ZXing.Net.Mobile Getting Started