我正在使用MEF与prism 6.0和MVVM。
1.为Leafmenu创建Menuviewmodel类，为Toplevel menu创建TopLevel MenuViewmodel类。Menuviewmodel类将具有您想要绑定菜单的所有属性。实现此接口的Moduleui必须具有以下属性：[Export(typeof(IMenu))]。
public class MenuViewModel:ViewModelBase
{
public String Name { get; private set; }
public UIMenuOptions ParentMenu { get; private set; }
private bool _IsToolTipEnabled;
public bool IsToolTipEnabled
{
get
{
return _IsToolTipEnabled;
}
set
{
SetField(ref _IsToolTipEnabled, value);
}
}
private String _ToolTipMessage;
public String ToolTipMessage
{
get
{
return _ToolTipMessage;
}
set
{
SetField(ref _ToolTipMessage, value);
}
}
private IExtensionView extensionView;
public MenuViewModel(String name, UIMenuOptions parentmenu,
bool isMenuCheckable = false,
IExtensionView extensionView =null)
{
if(name.Contains('_'))
{
name= name.Replace('_', ' ');
}
name = "_" + name;
this.Name = name;
this.ParentMenu = parentmenu;
this.IsMenuCheckable = isMenuCheckable;
this.extensionView = extensionView ;
}
private RelayCommand<object> _OpenMenuCommand;
public ObservableCollection<MenuViewModel> MenuItems { get; set; }
public ICommand OpenMenuCommand
{
get
{
if(_OpenMenuCommand==null)
{
_OpenMenuCommand = new RelayCommand<object>((args =>
OpenMenu(null)));
}
return _OpenMenuCommand;
}
}
private void OpenMenu(object p)
{
if (extensionView != null)
{
extensionView .Show();
}
}
private bool _IsMenuEnabled=true;
public bool IsMenuEnabled
{
get
{
return _IsMenuEnabled;
}
set
{
SetField(ref _IsMenuEnabled, value);
}
}
public bool IsMenuCheckable
{
get;
private set;
}
private bool _IsMenuChecked;
public bool IsMenuChecked
{
get
{
return _IsMenuChecked;
}
set
{
SetField(ref _IsMenuChecked, value);
}
}
}
public class ToplevelMenuViewModel:ViewModelBase
{
public ObservableCollection<MenuViewModel> ChildMenuViewModels {
get; private set; }
public String Header { get; private set; }
public ToplevelMenuViewModel(String header,
IEnumerable<MenuViewModel> childs)
{
this.Header ="_"+ header;
this.ChildMenuViewModels =new
ObservableCollection<MenuViewModel>(childs);
}
}
}
创建一个IMenu接口，它具有MenuViewModel属性。
public interface IMenu
{
MenuViewModel ExtensionMenuViewModel
{
get;
}
}
3. 您需要在所有模块的ModuleUi中实现IMenu接口，以便将其加载到菜单中。
4. 实现MefBootstrapper
5. 重写Configure聚合目录方法
6. 向目录添加包含所有模块dll和IMenu接口dll的目录。代码如下：
protected override void ConfigureAggregateCatalog()
{
base.ConfigureAggregateCatalog();
AggregateCatalog.Catalogs.Add(new
AssemblyCatalog(typeof(Bootstrapper).Assembly));
AggregateCatalog.Catalogs.Add(new
AssemblyCatalog(typeof(IMenu).Assembly));
DirectoryCatalog dc = new DirectoryCatalog(@".\Extensions");
AggregateCatalog.Catalogs.Add(dc);
}
7. 在你的主项目中添加对IMenu接口dll的引用。
8. 在mainwindow.xaml.cs类中声明一个属性。
public ObservableCollection ClientMenuViewModels
{ get; private set; }
声明一个私有字段。
private IEnumerable menuExtensions;
在你的主窗口或者 shell 构造函数中:
[ImportingConstructor]
public MainWindow([ImportMany] IEnumerable menuExtensions)
{
this.menuExtensions = menuExtensions;
this.DataContext=this;
}
private void InitalizeMenuAndOwners()
{
if (ClientMenuViewModels == null)
{
ClientMenuViewModels = new ObservableCollection();
}
else
{
ClientMenuViewModels.Clear();
}
if (menuExtensions != null)
{
var groupings = menuExtensions.Select(mnuext => mnuext.ClientMenuViewModel).GroupBy(mvvm => mvvm.ParentMenu);
foreach (IGrouping grouping in groupings)
{
UIMenuOptions parentMenuName = grouping.Key;
ToplevelMenuViewModel parentMenuVM = new ToplevelMenuViewModel(parentMenuName.ToString(),
grouping.Select(grp => { return (MenuViewModel)grp; }));
ClientMenuViewModels.Add(parentMenuVM);
}
}
}
}
在你的Shell.xaml或Mainwindow.xaml中定义一个菜单区域，并将itemssource属性绑定到ClientMenuViewModels。
<Menu HorizontalAlignment="Left"
Background="#FF0096D6"
Foreground="{StaticResource menuItemForegroundBrush}"
ItemsSource="{Binding ClientMenuViewModels}"
TabIndex="3">
<Menu.Resources>
<Style x:Key="subMneuStyle" TargetType="{x:Type MenuItem}">
<Setter Property="Foreground" Value="#FF0096D6" />
<Setter Property="FontFamily" Value="HP Simplified" />
<Setter Property="FontSize" Value="12" />
<Setter Property="Background" Value="White" />
<Setter Property="Command" Value="{Binding
OpenMenuCommand}" />
<Setter Property="IsCheckable" Value="{Binding
IsMenuCheckable}" />
<Setter Property="IsChecked" Value="{Binding
IsMenuChecked, Mode=TwoWay}" />
<Setter Property="IsEnabled" Value="{Binding
IsMenuEnabled, Mode=TwoWay}" />
<Setter Property="ToolTip" Value="{Binding
ToolTipMessage, Mode=OneWay}" />
<Setter Property="ToolTipService.ShowOnDisabled" Value="
{Binding IsToolTipEnabled, Mode=OneWay}" />
<Setter Property="ToolTipService.IsEnabled" Value="
{Binding IsToolTipEnabled, Mode=OneWay}" />
<Setter Property="ToolTipService.ShowDuration"
Value="3000" />
<Setter Property="ToolTipService.InitialShowDelay"
Value="10" />
</Style>
<my:MyStyleSelector x:Key="styleSelector" ChildMenuStyle="
{StaticResource subMneuStyle}" />
<HierarchicalDataTemplate DataType="{x:Type
plugins:ToplevelMenuViewModel}"
ItemContainerStyleSelector="{StaticResource styleSelector}"
ItemsSource="{Binding ChildMenuViewModels}">
<Label Margin="0,-5,0,0"
Content="{Binding Header}"
FontFamily="HP Simplified"
FontSize="12"
Foreground="{StaticResource menuItemForegroundBrush}" />
</HierarchicalDataTemplate>
<DataTemplate DataType="{x:Type plugins:MenuViewModel}">
<Label VerticalContentAlignment="Center"
Content="{Binding Name}"
Foreground="#FF0096D6" />
</DataTemplate>
</Menu.Resources>
<Menu.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</Menu.ItemsPanel>
</Menu>
public class MyStyleSelector : StyleSelector
{
public Style ChildMenuStyle { get; set; }
public Style TopLevelMenuItemStyle { get; set; }
public override Style SelectStyle(object item, DependencyObject
container)
{
if (item is MenuViewModel)
{
return ChildMenuStyle;
}
//if(item is ToplevelMenuViewModel)
//{
// return TopLevelMenuItemStyle;
//}
return null;
}
}
这里是ViewModelBase类。
public class ViewModelBase:INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
PropertyChangedEventHandler handler =Volatile.Read(ref PropertyChanged);
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(propertyName));
};
}
protected bool SetField<T>(ref T field, T value,[CallerMemberName] string propertyName="")
{
if (EqualityComparer<T>.Default.Equals(field, value)) return false;
field = value;
OnPropertyChanged(propertyName);
return true;
}
}
RelayCommand类如下：
public class RelayCommand<T> : ICommand
{
#region Fields
private readonly Action<T> _execute = null;
private readonly Predicate<T> _canExecute = null;
#endregion
#region Constructors
public RelayCommand(Action<T> execute)
: this(execute, null)
{
}
public RelayCommand(Action<T> execute, Predicate<T> canExecute)
{
if (execute == null)
throw new ArgumentNullException("execute");
_execute = execute;
_canExecute = canExecute;
}
#endregion
#region ICommand Members
public bool CanExecute(object parameter)
{
return _canExecute == null ? true : _canExecute((T)parameter);
}
public event EventHandler CanExecuteChanged
{
add
{
if (_canExecute != null)
CommandManager.RequerySuggested += value;
}
remove
{
if (_canExecute != null)
CommandManager.RequerySuggested -= value;
}
}
public void Execute(object parameter)
{
_execute((T)parameter);
}
#endregion
}
