xamarin.forms

问题 I have a property representing an actor private Actor _actor; public Actor Actor { get => _actor; set { if (_actor != value) { _actor = value; OnPropertyChanged("Actor"); } } } and a list, with a checkmark that depends on the state of Actor . When I click over the label the state of Actor shall change the checkmark private async void OnSelectionAsync(object item) { Actor = item; but I cannot see the changes in my ListView , why? Edit 1: in my list, i am binding the actor Text="{Binding Actor

问题 Xamarin.forms is working fine in android phones but in window8 emulator it is not loading image and giving invalid cross thread access exception. I'm using Embedded Image Technique, I'm storing all images in common folder and accessing from shared project. snapshot of my project is as follows: Error is As follows : In window8 simulator images are not loading Any help will be much appreciated. 回答1: This is because you are updating a UI element on a non UI thread, you want to use Device

问题 I am developing xamarin.ios application using Visual studio 2019 on PC which paired with late 2011 Macbook Pro. Today I accidentally updated the Visual studio to Version 16.5.4 . Which Updated the xamrin.ios to Version 13.16.0.13(b75deaf) . After that I can't able to run application. The visual studio tells to update the Xcode to 11.4 Which is currenlty 11.3. In order to do that I need to update the OS to catelina.,which is not provided for the old mac(also I don't want to upgrade). Apart

问题 I am developing xamarin.ios application using Visual studio 2019 on PC which paired with late 2011 Macbook Pro. Today I accidentally updated the Visual studio to Version 16.5.4 . Which Updated the xamrin.ios to Version 13.16.0.13(b75deaf) . After that I can't able to run application. The visual studio tells to update the Xcode to 11.4 Which is currenlty 11.3. In order to do that I need to update the OS to catelina.,which is not provided for the old mac(also I don't want to upgrade). Apart

问题 I have an application in which I have a requirement to take multiple images in one shot by phone camera. User don't want to open camera again and again. I have tried https://github.com/jamesmontemagno/MediaPlugin Plugin also but it do not support continuous Images capturing. It clicks one image at a time. Is there a way to achieve this behaviour? Thanks 回答1: Can you try this in media plugin for (int i = 0; i < 3; i++) { file = await MediaPicker.TakePhotoAsync(new StoreCameraMediaOptions {

问题 Using VS 2017 15.4.0 Following James Montemagno "Upgrading to Xamarin.Forms to .NET Standard" https://channel9.msdn.com/Shows/XamarinShow/Snack-Pack-15-Upgrading-to-XamarinForms-to-NET-Standard?ocid=player When trying to Clean/Build I am receiving the error: Severity Code Description Project File Line Suppression State Error Duplicate 'EmbeddedResource' items were included. The .NET SDK includes 'EmbeddedResource' items from your project directory by default. You can either remove these items

问题 Using VS 2017 15.4.0 Following James Montemagno "Upgrading to Xamarin.Forms to .NET Standard" https://channel9.msdn.com/Shows/XamarinShow/Snack-Pack-15-Upgrading-to-XamarinForms-to-NET-Standard?ocid=player When trying to Clean/Build I am receiving the error: Severity Code Description Project File Line Suppression State Error Duplicate 'EmbeddedResource' items were included. The .NET SDK includes 'EmbeddedResource' items from your project directory by default. You can either remove these items

问题 I'm new to C# and Xamarin Forms. I'm having a webview and getting source url from an API. (For this question , I have hardcode the value). I binded source url instead of adding the value to Source in XAML. But it's not working. There are few solutions in stack and forums. I tried. But didn't work. Someone please help me to sovle this. This is my XAML <?xml version="1.0" encoding="UTF-8"?> <ContentPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx

问题 Default FirebaseApp is not initialized in this process. Make sure to call FirebaseApp.initializeApp(Context) first. i have tried with many things but i am not able to Get notifications in devices. i also tried with below thing. In the Properties pane, set the Build Action Select google-services.json in the Solution Explorer window. In the Properties pane, set the Build Action to GoogleServicesJson (if the GoogleServicesJson build action is not shown, save and close the Solution, then reopen

问题 I am having a difficult time finding documentation on background tasks support for Xamarin.Forms. Does Xamarin.Forms provide support for periodic background tasks? I need to implement this for both Windows Phone 10 and Android. 回答1: XF has no implementation for background tasks. You will need to implement these natively. Below are examples on how to do it for each type of project. UWP https://github.com/Microsoft/Windows-universal-samples/tree/master/Samples/BackgroundTask Android https:/