Dialog对话服务

创建弹窗控件

在View中创建用户控件：MsgView。然后创建一个业务层处理逻辑：MsgViewModel的类，类继承IDialogAware方法，实现如下接口

using Prism.Commands;
using Prism.Mvvm;
using Prism.Services.Dialogs;
using System;
using System.Collections.Generic;
using System.Text;

namespace BlankCoreApp1.ViewModels
{
    public class MsgViewModel :IDialogAware
    {
        public string Title
        {
            get { return title; }
            set { title = value;RaisePropertyChanged(); }
        }


        public event Action<IDialogResult> RequestClose;

        /// <summary>
        /// 允许用户关闭窗口
        /// </summary>
        /// <returns></returns>
        public bool CanCloseDialog()
        {
            return true;
        }

        /// <summary>
        /// 用户关闭方法
        /// </summary>
        public void OnDialogClosed()
        {
            
        }

        /// <summary>
        /// 接收参数
        /// </summary>
        /// <param name="parameters"></param>
        public void OnDialogOpened(IDialogParameters parameters)
        {
           
        }
    }
}

实现手动关联

在App.xaml.cs中实现手动关联

protected override void RegisterTypes(IContainerRegistry containerRegistry)
{
    // 建立手动关联  "Question"为别名
    containerRegistry.RegisterDialog<MsgView, MsgViewModel>("Question");
}

实现弹窗

在MainWindowViewModel中实现IDialogService服务

using Prism.Commands;
using Prism.Mvvm;
using Prism.Regions;
using Prism.Services.Dialogs;
using System;
using System.Windows;

namespace BlankCoreApp1.ViewModels
{
    public class MainWindowViewModel : BindableBase
    {
        private readonly IRegionManager regionManager;
        private readonly IDialogService dialog; // 弹窗服务
        IRegionNavigationJournal journal; // 导航日志的接口


        public DelegateCommand OpenACommand { get; private set; }
        public DelegateCommand OpenBCommand { get; private set; }
        public DelegateCommand GoBackCommand { get; private set; }
        public DelegateCommand GoForwordCommand { get; private set; }

        public MainWindowViewModel(IRegionManager regionManager,IDialogService dialog)
        {
            OpenACommand = new DelegateCommand(OpenA);
            OpenBCommand = new DelegateCommand(OpenB);
            GoBackCommand = new DelegateCommand(GoBack);
            GoForwordCommand = new DelegateCommand(GoForword);
            this.regionManager = regionManager;
            this.dialog = dialog;
        }

        private void GoForword()
        {
            journal.GoForward();
        }

        private void GoBack()
        {
            journal.GoBack();
        }

        private void OpenB()
        {
            // 设置区域内容为ViewB的内容。 使用回调函数arg来拿到导航日志
            regionManager.RequestNavigate("ContentRegion", "ViewB", arg =>
            {
                journal = arg.Context.NavigationService.Journal;
            });
        }

        private void OpenA()
        {
            // 弹窗
            dialog.ShowDialog("Question");
        }
    }
}

实现参数传递

使用DialogParameters，键值对的方式传递参数

private void OpenA()
{
    // 传递参数
    DialogParameters param = new DialogParameters();
    param.Add("Value", "Hello");

    // 弹窗 arg为回调结果
    dialog.ShowDialog("Question",param,arg=>
    { 
        // 处理返回结果
        if(arg.Result == ButtonResult.OK)
        {
            
        }
        
    });

}

获取传递参数

在MsgViewModel中获取传递的参数

public void OnDialogOpened(IDialogParameters parameters)
{
   var title =  parameters.GetValue<string>("Value");
}

实现按钮命令绑定

创建两个按钮命令并进行初始化

using Prism.Commands;
using Prism.Mvvm;
using Prism.Services.Dialogs;
using System;
using System.Collections.Generic;
using System.Text;

namespace BlankCoreApp1.ViewModels
{
    public class MsgViewModel :BindableBase, IDialogAware
    {
        public MsgViewModel()
        {
            SaveCommand = new DelegateCommand(() =>
            {
                DialogParameters param = new DialogParameters();
                param.Add("Value", Title);
                RequestClose.Invoke(new DialogResult(ButtonResult.OK, param));

            });
            CancelCommand = new DelegateCommand(() => 
            {
                RequestClose.Invoke(new DialogResult(ButtonResult.No));
            });


        }

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

        // 属性通知
        private string title;
        public string Title
        {
            get { return title; }
            set { title = value;RaisePropertyChanged(); }
        }


        public event Action<IDialogResult> RequestClose;

        /// <summary>
        /// 允许用户关闭窗口
        /// </summary>
        /// <returns></returns>
        public bool CanCloseDialog()
        {
            return true;
        }

        /// <summary>
        /// 用户关闭方法
        /// </summary>
        public void OnDialogClosed()
        {
            
        }

        /// <summary>
        /// 接收参数
        /// </summary>
        /// <param name="parameters"></param>
        public void OnDialogOpened(IDialogParameters parameters)
        {
           var title =  parameters.GetValue<string>("Value");
        }
    }
}

实现绑定命令到按钮

在MsgView.xaml中对按钮实现命令绑定

<Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"/>
            <RowDefinition/>
            <RowDefinition Height="auto"/>

        </Grid.RowDefinitions>
        <TextBlock 
            HorizontalAlignment="Stretch"
            VerticalAlignment="Center"
            FontSize="30"
            Text="编辑窗口"
            />
        <TextBox
            Grid.Row="1"
            Margin="5"
            HorizontalAlignment="Stretch"
            VerticalAlignment="Center"
            FontSize="30"
            Text="{Binding Title}"
            />
        <StackPanel
            Grid.Row="2"
            HorizontalAlignment="Right"
            Orientation="Horizontal">
            <Button
                Width="100"
                Height="35"
                Margin="10"
                Command="{Binding SaveCommand}"
                Content="确定"
                FontSize="22"
                />
            <Button
                Width="100"
                Height="35"
                Margin="10"
                Command="{Binding CancelCommand}"
                Content="取消"
                FontSize="22"
                />
        </StackPanel>
  </Grid>

实现返回结果判断

在回调函数中对result进行接收和判断。

dialog.ShowDialog("Question",param,arg=>
{ 
    // 处理返回结果
    if(arg.Result == ButtonResult.OK)
    {
        var value = arg.Parameters.GetValue<string>("Value");
        MessageBox.Show($"用户输入了：{value}");
    }
    else
    {
        MessageBox.Show("用户取消了弹窗");
    }
});