Dialog

1.自定义对话框xaml

<UserControl x:Class="NavigationApp.Views.MyDialog"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:NavigationApp.Views"
             mc:Ignorable="d"              
             d:DesignHeight="450" d:DesignWidth="800">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"/>
            <RowDefinition/>
            <RowDefinition Height="auto"/>
        </Grid.RowDefinitions>

        <TextBlock Text="编辑" FontSize="22"/>
        <TextBox Grid.Row="1" Text="{Binding Title}" Height="30" Margin="15"/>
        <StackPanel Grid.Row="2" Orientation="Horizontal" HorizontalAlignment="Right">
            <Button Content="OK" Margin="5" Padding="3" FontSize="22" Command="{Binding SaveCommand}"/>
            <Button Content="Cancel" Margin="5" Padding="3" FontSize="22" Command="{Binding CancelCommand}"/>
        </StackPanel>
    </Grid>
</UserControl>

2.对话框ViewModel

    public class MyDialogViewModel : BindableBase, IDialogAware
    {
        public MyDialogViewModel() 
        {
            SaveCommand = new DelegateCommand(() =>
            {
                DialogParameters keyValuePairs = new DialogParameters();
                keyValuePairs.Add("value", Title);
                RequestClose?.Invoke(new DialogResult(ButtonResult.OK, keyValuePairs));
            });
            CancelCommand = new DelegateCommand(() =>
            {
                RequestClose?.Invoke(new DialogResult(ButtonResult.Cancel)); ;
            });
        }

        public DelegateCommand SaveCommand { get; set; }
        public DelegateCommand CancelCommand { get; set; }

        private string title;
        public string Title
        {
            get { return title; }
            set
            {
                title = value;
                RaisePropertyChanged("Title");
            }
        }

        public event Action<IDialogResult> RequestClose;

        public bool CanCloseDialog()
        {
            return true;
        }

        public void OnDialogClosed()
        {
        }

        public void OnDialogOpened(IDialogParameters parameters)
        {
            Title = parameters.GetValue<string>("value");
        }
    }

3.调用对话框

//App.cs中注册
containerRegistry.RegisterDialog<MyDialog, MyDialogViewModel>("Question");

//显示
        private void ShowDLG()
        {
            DialogParameters pairs = new DialogParameters();
            pairs.Add("value", "Test1");
            dialog.ShowDialog("Question", pairs, arg =>
            {
                if (arg.Result == ButtonResult.OK)
                {
                    var value = arg.Parameters.GetValue<string>("value");
                    MessageBox.Show(value);
                }
                else
                {
                    MessageBox.Show("取消了");
                }
            });
        }