Wpf 使用 Prism 实战开发Day23

自定义对话框服务

当原有对话框不能满足需求的时候，可以通过自定义对话框来实现特殊的需求

一.自定义对话框主机服务步骤：

1.建立一个IDialogHostService 接口类，继承自 IDialogService 对话框服务类。并且自定义基类的服务方法。

public interface IDialogHostService:IDialogService
{
    Task<IDialogResult> ShowDialog(string name,IDialogParameters parameters,string dialogHostName="Root");
}

2.创建一个 IDialogHostAware 接口类

    public interface IDialogHostAware
    {
        //Dialoghost 名称
        string DialogHostName { get; set; }

        //打开窗口过程中所接收的参数
        void OnDialogOpend(IDialogParameters parameters);
        //取消命令
        DelegateCommand CancelCommand { get; set; }
        //保存命令
        DelegateCommand SaveCommand { get; set; }

    }

2.接着，实现基类自定义主机服务的方法

/// <summary>
/// 自定义对话主机服务
/// </summary>
public class DialogHostService : DialogService, IDialogHostService
{
    private readonly IContainerExtension _containerExtension;

    public DialogHostService(IContainerExtension containerExtension) : base(containerExtension)
    {
        this._containerExtension = containerExtension;
    }

    public async Task<IDialogResult> ShowDialog(string name, IDialogParameters parameters, string dialogHostName = "Root")
    {
        parameters ??= new DialogParameters();
        //从容器中取出弹出窗口的实例
        var content=  _containerExtension.Resolve<object>(name);
        //验证实例有效性
        if (!(content is FrameworkElement dialogContent))
            throw new NullReferenceException("A dialog's content must be a FrameworkElement");
        if (dialogContent is FrameworkElement view && view.DataContext is null && ViewModelLocator.GetAutoWireViewModel(view) is null)
        {
            ViewModelLocator.SetAutoWireViewModel(view, true);
        }
        if (!(dialogContent.DataContext is IDialogHostAware viewModel))
            throw new NullReferenceException("A dialog's ViewModel must implement the IDialogAware interface");

        viewModel.DialogHostName = dialogHostName;
        //打开过程中，所执行的事件
        DialogOpenedEventHandler eventHandle = (sender, args) =>
        {
            if (viewModel is IDialogHostAware aware)
            {
                aware.OnDialogOpend(parameters);
            }
            args.Session.UpdateContent(content);
        };
       return (IDialogResult) await DialogHost.Show(dialogContent, viewModel.DialogHostName, eventHandle);
    }
}

二.把对话框主机服务，进行依赖注册。

containerRegistry.Register<IDialogHostService, DialogHostService>();

三.修改ViewModels 中Dialog 文件夹中待办事项和备忘录弹窗视图继承逻辑

1.修改 AddToDoViewModel后台处理逻辑类继承自IDialogHostAware

 public class AddToDoViewModel : IDialogHostAware
 {
     public AddToDoViewModel()
     {
         CancelCommand = new DelegateCommand(Cancel);
         SaveCommand = new DelegateCommand(Save);
     }

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

     public void OnDialogOpend(IDialogParameters parameters)
     {

     }
     private void Cancel()
     {
         if (DialogHost.IsDialogOpen(DialogHostName)) //是否是打开
         {
             DialogHost.Close(DialogHostName,new DialogResult(ButtonResult.No)); //关闭
         }
     }
     private void Save()
     {
         if (DialogHost.IsDialogOpen(DialogHostName)) //是否是打开
         {
             DialogParameters pairs = new DialogParameters(); //定义返回参数
             DialogHost.Close(DialogHostName, new DialogResult(ButtonResult.OK, pairs));
         }
     }

 }

2.修改 AddMemoViewModel 后台处理逻辑类继承自IDialogHostAware

public class AddMemoViewModel : IDialogHostAware
{
    public AddMemoViewModel()
    {
        CancelCommand = new DelegateCommand(Cancel);
        SaveCommand = new DelegateCommand(Save);
    }

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

    public void OnDialogOpend(IDialogParameters parameters)
    {
       
    }
    private void Cancel()
    {
        if (DialogHost.IsDialogOpen(DialogHostName)) //是否是打开
        {
            DialogHost.Close(DialogHostName,new DialogResult(ButtonResult.No)); //关闭
        }   
    }
    private void Save()
    {
        if (DialogHost.IsDialogOpen(DialogHostName)) //是否是打开
        {
            DialogParameters pairs = new DialogParameters(); //定义返回参数
            DialogHost.Close(DialogHostName,new DialogResult (ButtonResult.OK,pairs)); 
        }
    }

}

3.修改弹窗视图待办事项和备忘录，给按钮添加命令绑定

4.最后再修改原弹窗注册服务，直接添加进容器中即可。

四. 修改 IndexViewModel 处理逻辑

public class IndexViewModel:BindableBase
{
    public IndexViewModel(IDialogHostService dialogService)
    {
        TaskBars=new ObservableCollection<TaskBar>();
        ToDoDtos = new ObservableCollection<ToDoDto>();
        MemoDtos = new ObservableCollection<MemoDto>();
        ExecuteCommand = new DelegateCommand<string>(Execute);
        CreateTaskBars();
        CreateTestDate();
        this.dialogService = dialogService;
    }

    public DelegateCommand<string> ExecuteCommand { get; private set; }
        
    private ObservableCollection<TaskBar> taskBars;

    public ObservableCollection<TaskBar> TaskBars
    {
        get { return taskBars; }
        set { taskBars = value; RaisePropertyChanged(); }
    }
    private ObservableCollection<ToDoDto> toDoDtos;

    public ObservableCollection<ToDoDto> ToDoDtos
    {
        get { return toDoDtos; }
        set { toDoDtos = value; RaisePropertyChanged(); }
    }
    private ObservableCollection<MemoDto> memoDtos;
    private readonly IDialogHostService dialogService;

    public ObservableCollection<MemoDto> MemoDtos
    {
        get { return memoDtos; }
        set { memoDtos = value; RaisePropertyChanged(); }
    }
    void CreateTaskBars()
    {
        TaskBars.Add(new TaskBar() { Icon="ClockFast",Title="汇总",Content="9",Color="#FF0CA0FF",Target=""});
        TaskBars.Add(new TaskBar() { Icon = "ClockCheckOutline", Title = "已完成", Content = "9", Color = "#FF1ECA3A", Target = "" });
        TaskBars.Add(new TaskBar() { Icon = "ChartLineVariant", Title = "完成比例", Content = "9%", Color = "#FF02C6DC", Target = "" });
        TaskBars.Add(new TaskBar() { Icon = "PlaylistStar", Title = "备忘录", Content = "18", Color = "#FFFFA000", Target = "" });
    }
    void CreateTestDate()
    {
        
        for (int i = 0; i < 10; i++)
        {
            ToDoDtos.Add(new ToDoDto { Title="待办"+i,Content="正在处理中.."});
            MemoDtos.Add(new MemoDto { Title = "备忘" + i, Content = "我的密码" });
        }
    }
    private void Execute(string obj)
    {
       switch(obj)
        {
            case "新增备忘录":
                dialogService.ShowDialog("AddMemoView",null, "RootDialog");
                break;
            case "新增待办事项":
                dialogService.ShowDialog("AddToDoView",null, "RootDialog");
                break;
        }
    }
}