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Xamarin has no control over code control

For my Xamarin forms project (latest version 1.3), when I create a view in Xamarin Studio (latest version, 5.5.4), I have defined the view like this:

<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" x:Class="FormsDemo.Register">
    <ContentPage.Content>

        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition />
                <RowDefinition />
                <RowDefinition />
                <RowDefinition />
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="100" />
                <ColumnDefinition />
            </Grid.ColumnDefinitions>

            <Label Grid.Row="0" Grid.Column="0" Text="First Name" />
            <Entry x:Name="FirstName" Grid.Row="0" Grid.Column="1" />

            <Label Grid.Row="1" Grid.Column="0" Text="Last Name" />
            <Entry x:Name="LastName" Grid.Row="1" Grid.Column="1" />

            <Label Grid.Row="2" Grid.Column="0" Text="Email" />
            <Entry x:Name="Email" Grid.Row="2" Grid.Column="1" />

            <Button x:Name="SaveButton" Grid.Row="3" Grid.Column="0" Text="Login" />
        </Grid>

    </ContentPage.Content>
</ContentPage>

However, in my code, any reference to the control by name was not found at all. The following code is an error (noted by comments):

using System;
using System.Collections.Generic;
using Xamarin.Forms;

namespace FormsDemo
{   
    public partial class Register : ContentPage
    {   
        public Register ()
        {
            InitializeComponent ();

            //Using this approach worked, but is not ideal
            this.FindByName<Button>("SaveButton").Clicked += Save_Clicked;
        }

        void Save_Clicked (object sender, EventArgs e)
        {
            this.FirstName.Text = "A";
            this.LastName.Text= "B";
        }
    }
}

Oddly enough, I was getting warnings with:

Warning: the private field `FormsDemo.Register.FirstName 'is assigned but its value is never used (FormsDemo.Solution)

I am getting one for each field. Why doesn't it work? How do I get intellisense to work?

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4 answers


The latest update seems to fix the problem; these links work fine:

this.FirstName.Text = "A";
this.LastName.Text= "B";


It looks like some issues with the designer have been resolved.

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I had a similar problem. In my case, it was my own business. In the xaml file, I have set the content x: Class attribute to the wrong value.

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
         xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
         x:Class="**{namespace.classname}**">


Specifying the class name correctly resolved the problem for me.

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I had the same problem after I renamed some files and manually fixed the class references. Somehow VS couldn't find links from the xaml page. When I created a new xaml file with the code behind, the same code worked.

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you can try this

var asdf = this.FindByName<TimePicker>("tagName");

here SUGGESTIONS :

https://forums.xamarin.com/discussion/25409/problem-with-xaml-x-name-and-access-from-code-behind

DIRECT ANSWER from this link

In the page properties, check if the following properties are set:

BuildAction = built-in resource CustomTool = MSBuild: UpdateDesignTimeXaml

If everything is ok, delete the obj and bin folders, rebuild the PCL.

If you import a XAML page into PCL, for example, the attributes will change and will not compile.

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