xamarin.forms

问题 I started out creating a .NET Standard Library that I intended to make a NuGet of - but came to find that I also needed platform-specific functionality. So, I found this stack overflow question - which indicated I could use a Multiplatform Library template instead. But here I encountered a problem with DependencyService - and a problem with Custom Renderer - effectively meaning that there was no way for the non-platform-specific to communicate with platform-specific code in the library. I

问题 I've noticed that when I customize flyout item appearance like it says here in the docs, the current FlyoutItem is not marked anymore. Snip of the code from docs to change the item appearance: <Shell ...> ... <Shell.ItemTemplate> <DataTemplate> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="0.2*" /> <ColumnDefinition Width="0.8*" /> </Grid.ColumnDefinitions> <Image Source="{Binding FlyoutIcon}" Margin="5" HeightRequest="45" /> <Label Grid.Column="1" Text="{Binding Title}"

问题 I started out creating a .NET Standard Library that I intended to make a NuGet of - but came to find that I also needed platform-specific functionality. So, I found this stack overflow question - which indicated I could use a Multiplatform Library template instead. But here I encountered a problem with DependencyService - and a problem with Custom Renderer - effectively meaning that there was no way for the non-platform-specific to communicate with platform-specific code in the library. I

问题 I Have to read data from UsbDeviceConnection but the call UsbDeviceConnection.BulkTransfer(......) always returns -1. when I have to write data, all works fine, but when I try to receive, the call always returns -1 (receive failed). [Obsolete] public string ConnectAndRead() { // Get a usbManager that can access all of the devices var usbManager = (UsbManager)Forms.Context.GetSystemService(Context.UsbService); while(usbManager.DeviceList.Count == 0) { Debug.WriteLine($"Nessun dispositivo

问题 I Have to read data from UsbDeviceConnection but the call UsbDeviceConnection.BulkTransfer(......) always returns -1. when I have to write data, all works fine, but when I try to receive, the call always returns -1 (receive failed). [Obsolete] public string ConnectAndRead() { // Get a usbManager that can access all of the devices var usbManager = (UsbManager)Forms.Context.GetSystemService(Context.UsbService); while(usbManager.DeviceList.Count == 0) { Debug.WriteLine($"Nessun dispositivo

问题 Here is the Code (Run this to see what's the problem) => https://github.com/x0axz/CustomRenderer In my Xamarin App, there is a Custom Camera Renderer for Android, which is being called from ViewModel through MessagingCenter.Send<object>(this, "A"); . It's working fine. The only problem is that, on first page it takes Picture, but when I navigate to another page, where there is an other command, MessagingCenter.Send<object>(this, "A"); , to take a Picture, but this time it returns an error

问题 I've created a fresh Xmarain.Forms project and a fresh Xmarain.Forms UI Tests project. I've managed to get the freshly created Android apk built and installed to my emulated device. My Unit Tests application is able to connect to the installed apk. When it attempts to run the first test I get the following error though: System.Net.WebException : POST Failed at Xamarin.UITest.Shared.Http.HttpClient.HandleHttpError(String method, HttpResponseMessage response, ExceptionPolicy exceptionPolicy) at

问题 I've created a fresh Xmarain.Forms project and a fresh Xmarain.Forms UI Tests project. I've managed to get the freshly created Android apk built and installed to my emulated device. My Unit Tests application is able to connect to the installed apk. When it attempts to run the first test I get the following error though: System.Net.WebException : POST Failed at Xamarin.UITest.Shared.Http.HttpClient.HandleHttpError(String method, HttpResponseMessage response, ExceptionPolicy exceptionPolicy) at

问题 I have tried to make all the items in the itemtemplate into a single view as like in the below image, how to achieve this by using Xamarin CarouselView, i am using like this carousel = new CarouselView(); carousel.BindingContext = this; carousel.ItemTemplate = itemTemplate; carousel.SetBinding(CarouselView.ItemsSourceProperty, new Binding(nameof(this.Items), mode: BindingMode.OneWay)); LinearItemsLayout linearItemsLayout = new LinearItemsLayout(ItemsLayoutOrientation.Horizontal);

问题 I have tried to make all the items in the itemtemplate into a single view as like in the below image, how to achieve this by using Xamarin CarouselView, i am using like this carousel = new CarouselView(); carousel.BindingContext = this; carousel.ItemTemplate = itemTemplate; carousel.SetBinding(CarouselView.ItemsSourceProperty, new Binding(nameof(this.Items), mode: BindingMode.OneWay)); LinearItemsLayout linearItemsLayout = new LinearItemsLayout(ItemsLayoutOrientation.Horizontal);