Binding datacontext of a Usercontrol

Question

I'm starting in wpf app. And i'm trying to practice the MVVM patern. I'm having trouble to bind the datacontext of a Usercontrol.

<UserControl x:Class="Test.Views.Login.Identifer"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:vm="clr-namespace:Test.ViewModels"
mc:Ignorable="d"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
d:DesignHeight="480" d:DesignWidth="480">

<UserControl.DataContext>
    <vm:Login/>
</UserControl.DataContext>
<Grid x:Name="LayoutRoot" Background="{StaticResource PhoneChromeBrush}">
    <Grid.RowDefinitions>
        <RowDefinition></RowDefinition>
        <RowDefinition></RowDefinition>
    </Grid.RowDefinitions>
    <TextBox Name="user"></TextBox>
    <TextBox Grid.Row="1" Name="password"></TextBox>
</Grid>

this is my usercontrol and Login is my class that i want to bind to my datacontext. I put this usercontrol in my PhonApplicationPage:

<phone:PhoneApplicationPage
x:Class="Test.Views.Login.Login"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:Views="clr-namespace:Test.Views.Login"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
mc:Ignorable="d"
shell:SystemTray.IsVisible="True">

<!--LayoutRoot est la grille racine où tout le contenu de la page est placé-->
<Grid x:Name="LayoutRoot" Background="Transparent">
    <Views:Identifer></Views:Identifer>
</Grid>

And I'm going to finsih with my Login class:

using Test.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Test.ViewModels
{
class Login : MyNotifyPropertyChanged
{
    public Client client_ { get; set; }
    public Login()
    {
        client_ = new Client();
    }
}
}

And I'm having the following error: Erreur 1 Cannot create instance of type 'Test.ViewModels.Login' [Line: 14 Position: 19]

Thanks for the help.

Answer 1

您的班级应该是公开的时候是私人的

public class Login : MyNotifyPropertyChanged //add public keyword