Most voted "xamarin" questions
Use this tag for questions about the Xamarin platform, which enables you to develop native mobile apps for iOS and Android using C# in Mono or Visual Studio. Ideally a specific framework/product tag should be used, unless the problem is general for all editions.
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answers52
viewsLoading when searching JSON
I need to create a "Loading" when I click on a search button for JSON information on a site. Loading needs to be in the middle of the screen. Code: <?xml version="1.0" encoding="utf-8" ?>…
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answer25
viewsError while receiving Picker content
I have a client register and I need to change the registration of the same at some point, but to make the change I have to deal with a Picker field, only it is a mistake when I try to bring the…
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answers148
viewsImage Upload in Xamarin / c#
I am developing an application in Xamarin that I need to upload an image (both on Android and IOS), to a server. I looked for something on the internet and could not find. I’m using the PostAsync of…
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answer120
viewsMoney mask
I need to have in an entry a money mask, I’m trying some things I got information, follows: void lanceMask(object sender, EventArgs e) { var ev = e as TextChangedEventArgs; if (ev.NewTextValue !=…
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answer309
viewsSpace and color between Viewcell in a Listview
I would like to help because I’m not being able to leave the way I hope, there’s more space between colors. The gray is the background I put in and the yellow is being filled in by Binding. The red…
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answer86
viewsAccess carouselview inside a listview
I have a ListView and within it I have a CarouselView by the name of CarrosselDeImagens, but in code Behind I can’t access the CarouselView. Kind of: CarrosselDeImagens.ItemSource = listaImagens.…
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answer58
viewsListview Item Xamarin Forms being opened 2 times Custom Controls
When displaying my list and clicking on an item, it opens 2 times the same item page. public class DeliveryViewModel : BaseViewModel { public ObservableCollection<Delivery> Delivery_Col { get;…
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answer396
viewsGrid with spacing and Boxview
I am learning to use Grid and I have three questions in my project that even in tests or when following tutorials did not get good results in practice since I always saw being tested with Boxview:…
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answers79
viewsProblem with loading data from local bd to two pickers
Hello. I have two pickers that load data from an api. A Picker brings data from categories and the other subcategory. When selecting a category the Picker subcategory is loaded with data from the…
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answers27
viewsProblem with android agenda
I’m starting an interview to get a contact in the contact list: if (AceitouContacts) { Intent intent = new Intent(Intent.ActionPick, ContactsContract.CommonDataKinds.Phone.ContentUri);…
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answer357
viewsConsuming a WEB API in Visual Studio
I created a WEB API on Asp.net that is hosted on a web server. This WEB API accesses a table in SQL Server where I have a table called Products with Id, name, description and Price, I ran the tests…
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answers144
viewsHow to treat an empty entry?
I have 4 text entries and a button: <Entry x:Name="Densidade" Keyboard="Numeric"/> <Entry x:Name="Volume" Keyboard="Numeric"/> <Entry x:Name="Area" Keyboard="Numeric"/> <Entry…
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answer232
viewsHow to know if a button has been clicked? Xamarin Forms
I have sometimes needed to know when a button was clicked and did not find a property natively in C#/Xamarin. For example: In this image above we have a Entry with a Text (for example only) written…
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answers247
viewsHow to use values from each entry in Xamarin?
The code at the moment is like this, I am doing all the visual part in the Behind code even, without implementing anything directly in XAML. I create the number of Entries according to the value…
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answers40
viewsAudio Error in Android Virtual Machine
I’m studying a tutorial of Xamarin, and I’m trying to run every step of it on two different machines, only in one of them the emulator closes with the following error: Device error: audio: Failed to…
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answers13
viewsChanging the Source of a Listview that was created in Fragment
Where I change the font type and color in Listview control? Listview controls are in main.xaml as below: <ListView android:id="@+id/left_drawer" android:layout_width="240dp"…
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answer481
viewsError "Signature (Return type) of Eventhandler..."
Making a mistake: Signature (Return type) of Eventhandler "Foodsuppy.Tela.Solicitacaocompra.Btnincluir_clicked" doesn’t match the Event type Foodsuppy. My app buttons started giving this message…
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answer122
viewsHow to define a color using the <Color/> element of Xamarin Forms within a Resourcedictionary
Hello, I’m following you this tutorial and, starting from what it shows along with the Xamarin.Forms documentation, I can create a Resource Dictionary as follows: <?xml version="1.0"…
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answer59
viewsBinding with Customcontrol is not working
I created a Customcontrol but creating a Bindingproperty I cannot perform a Binding Custom Control XAML code <ContentView xmlns="http://xamarin.com/schemas/2014/forms"…
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answer364
viewsError in the shaman saying that the type was not found
In my shampoo I have: <?xml version="1.0" encoding="utf-8" ?> <ContentPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"…
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answer54
viewsError during Page Deletion - Xamarin
I’m new to mobile programming, so I wanted a help to treat an error that seems not set by the IDE (Visual Studio). The case is that I have a screen that wanted to insert that carousel with…
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answer98
viewsResolvelibraryprojectimports error in Xamarin
Good afternoon, I went to compile the APP I’m creating with Xamarin and I’m having the following error: Unexpected failure of "Resolvelibraryprojectimports" task. I already cleaned the solution,…
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answers60
viewsHow do I save this image in the gallery and access it again?
I have this Xamarin Android App (not Forms) that just opens the camera and allows me to take a photo and go with it or resume. After I say I want to keep it, it appears in the app in an Imageview…
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answer78
viewsConvert JSON file to object - C# Xamarin
I have the following JSON file: { "createdAt":"Apr 17, 2019 10:28:39", "id":"52329770-64e2-4759-9d3d-f2595973de4e", "items":[ { "id":"82d2e4ab-da74-45df-a9ea-99cc257ead59", "name":"REFRIGERANTE KS",…
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answers133
viewsRestsharp taking his time making the first requisition
I am making an application using Xamarin Native and I decided to use Restsharp to make the requests to my API, the problem is that the first request made takes a few seconds (some 3) to be made,…
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answers87
viewsC# - Application in Xamarin causing slowness after some time
Hello, All right? I am creating an application in Xamarin Forms, however I am having some problems of slowness. In this application, I use a lot of parallel processing, and the application works…
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answers141
viewsInterface and heritage in Xamarin - System.Invalidcastexception: Specified cast is not Valid
Greetings! I’m developing a Cross Platform project in Xamarin. This project consists of consuming a web-service method that will return the script code and an address array that corresponds to the…
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answer212
viewsAdded components in Xamarin Studio 4.x/5.x and Android Designer
When using the Xamarin Studio 4.x/5.x Designer Interface tool on the Windows 8/8.1 platform I cannot add components on the screen, when trying to drag and drop a component from the toolbar to the…
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answer91
viewsActivity does not open
Well, I created two Activities when I clicked on the button of the first one it should open the second one with information received from the first one. But that’s not what happens, where I’m wrong?…
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answer298
viewsHalf Gauge (Half Fleece) for Xamarin Forms
I need to build a half-circle gauge using Xamarin forms, paid controls do not meet because they only have Circular Gauges. It is even possible to display as half-circle, but wastes essential part of…
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answer111
viewsScript for first load Xamarin Android sqlite
I need to create a first load script for our application, the problem and we have two BLOB fields in our table, it is very large with this I would like to see the best way to implement this first…
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answer171
viewsOpen PDF on iOS mobile using Xamarin - C#
Does anyone know how to open a PDF that is in the local iOS folder using the Xamarin platform? I have researched and tested several ways, but none works.
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answer295
viewsXamarin error: Could not create the Java Virtual Machine
I’m having a designer startup problem wanted to know how to solve this problem Could not create the Java Virtual Machine Screen image:…
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answers62
viewsMismatch between Processor Architectures
I am completely new to the world of mobile application development. By trying to run a test application I get this error twice: There was a Mismatch between the Processor Architecture of the project…
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answer267
viewsError creating Xamarin Visual Studio Community 2015 project
Error creating a new project in visual studio using Xamarin…
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answer37
viewsUipickerview 3 columns
I want to make a uipickerview with three columns, but only the first appears loaded the other empty, I can not find the error if someone knows how to solve thanks. Follow the code below: static…
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answers331
viewsMy Imageview does not appear on my phone
I created a Layout and an Activity for this Layout. In Layout I only have an Imageview with a png image that is located in Resources/Drawables. When I Debug in the App Imageview does not appear on…
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answer94
viewsErro Xamarin - MVA Course Starting with Xamarin.Forms - Video 3
In compiling, I find the following mistake: Unhandled Exception: Xamarin.Forms.Xaml.Xamlparseexception: Position 9:15. No Property of name Itemsource found "Unhandled Exception:…
xamarinasked 8 years, 5 months ago Mauricio Ribeiro 11 -
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answer39
viewsErrors Reinstalling Microsoft Visual Audio
I was uninstalling for Iobit Microsoft Visual Studio & Xamarin, then tried to reinstall and is giving these errors. I have tried to uninstall deleting the folders from the files and the Logs on…
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answer130
viewsNative app performance is still far superior to html based app?
I am in doubt about which framework/language to use to start application development. From what I’ve read so far, I’m between using Ionic and Xamarin. Everywhere I read the great advantage of Ionic…
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answers42
viewsCan’t Convert error to color: type=0x2
In Xamarin, when debugging the application, this error appears Can’t Convert to color: type=0x2 in the method SetSupportActionBar(...); Excerpt: Android.Support.V7.Widget.Toolbar myToolbar =…
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answer693
viewsXamarin has some limitation for creating APP for Android
I’m starting to study mobile programming, specifically Android at the moment, and I’m having a question. I started studying the Android Studio which uses the JAVA language, but it is also possible…
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answer76
viewsAndroid SDK error could not be found
After clicking on the file Main.xml this error appeared: Android SDK error could not be found. How can I fix this?…
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answers52
viewsCannot save to native calendar - Xamarin - IOS
I am saving an event in the native calendar of IOS through the code below, by the simulator works perfectly, but when I do right on the device of the iPhone this code does not work. I did two tests…
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answer61
viewsHow to resize an image using UWP?
I have that code: var file = await ImageChooser.GetSelectedImageAsStorageFile(); var sasUri = await Vm.GetBlobSasUri(file.Name); var blob = await file.UploadToBlob(sasUri); await…
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answers316
viewsProblems with Jsonconvert.Serializeobject and Stringcontent
I am developing an application Xamarin Forms that will persist data via web service (PHP - Mysql), but I have problems sending data via POST I have the event below and the same from the message of…
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answers1230
viewsBack button on Xamarin Cross Platform
How to make a function for when to click "Back" on Android in Xamarin, the app goes back to the previous screen ?
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answer116
viewsXamarin.Forms.Xaml.Xamlparseexception
I am creating a Xamarin project for study, I have a Masterpage and inside it I have the code below: I am compiling for Android and I see that the problem is in this line:…
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answer513
viewsSend PHP POST request via Xamarin
I need to submit a request on POST for a php file through this application. This code worked correctly on Windows Forms, however in Xamarin it’s not working... public void testar() { try { string…
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answer163
viewsXamarin - Accessing API that returns JSON
Next, I am VERY new to this API issue. I created my first web application . net Framework 4.5.2. I created it very standard (according to VS 2015), and created a controller for testing…