模块化

乌龙茶原创2023年6月8日大约 4 分钟

开发包

提示

这里有很多关于Prism 示例

WPF 入门可以看下深入浅出WPF以及WPF编程宝典

Prism

数据库配置

表设计

树形菜单在数据库可配置，先设计菜单树模型，这里设计三个模型，SubSystem、SubMenu、MenuLink分别为模块、模块下的菜单、菜单对应的插件

初始化数据

提示

一个菜单一个插件，还是多个菜单一个插件都没关系

private const List<SubSystem> DefaultSubSystems=new List<SubSystem>(){
    new SubSystem() { SubCode = "AA", SubName = "A模块", Order = 1 },
    new SubSystem() { SubCode = "SS", SubName = "B模块", Order = 2 },
};

private const List<SubMenu> DefaultSubMenus= new List<SubMenu>(){
    new MenuEntity() { SubCode = "AA", MenuCode = "AA01", MenuName = "test1", SupMenuId = "AA", Grade = 1,Order = 1, EndGrade = true },
    new MenuEntity() { SubCode = "AA", MenuCode = "AA02", MenuName = "test2", SupMenuId = "AA", Grade = 1,Order = 2, EndGrade = true },
    new MenuEntity() { SubCode = "SS", MenuCode = "SS01", MenuName = "test3", SupMenuId = "SS", Grade = 1,Order = 1, EndGrade = false },
    new MenuEntity() { SubCode = "SS", MenuCode = "SS0101", MenuName = "test4", SupMenuId = "SS01", Grade = 2,Order = 1, EndGrade = false },
    new MenuEntity() { SubCode = "SS", MenuCode = "SS010101", MenuName = "test5", SupMenuId = "SS0101", Grade = 3,Order = 1, EndGrade = true },
    new MenuEntity() { SubCode = "SS", MenuCode = "SS010102", MenuName = "test6", SupMenuId = "SS0101", Grade = 3,Order = 2, EndGrade = true },
};

private const List<MenuLink> DefautlLinks = new List<MenuLink>(){
  new MenuLink() { MenuCode = "AA01" Assembly = "Demo.Plugin",Class = "Demo.Plugin.Entry"},
  new MenuLink() { MenuCode = "SS0101" Assembly = "Demo.Plugin",Class = "Demo.Plugin.Entry"},
};

DTO

将设计的三个表转换成 WPF 菜单树控件TreeView需要的数据模型TreeMenu

首先要确认的事，数据库设计可以配置无数层，但是 WPF 界面显示，深度不应太深，MAX_LEVEL属性进行控制

| --A         
| ----A1     
| ------A12

其中树形菜单的第一层为SubSystem的值。二三层对应SubMenu数据值

private const byte MAX_LEVEL=3;
private ObservableCollection<TreeMenu> _treeMenu;

public void LoadTreeMenu(){
    foreach (var sub in DefaultSubSystems){
        TreeMenu subTree = null;
        IterationMenu(DefaultSubMenus, ref subTree, sub, 1);
        if (subTree != null){
            _treeMenu.Add(subTree);
        }
    }
}

private void IterationMenu(List<SubMenu> source, ref TreeMenu treeParent, SubSystem parent, int grade)
{
    if (grade == MAX_LEVEL) return;
    if (treeParent == null) {
        treeParent = new TreeMenu{ TreeCode = parent.SubCode, TreeName = parent.SubName, Children = new List<TreeMenu>() };
        foreach (var child in source.Where(o => o.SupMenuId == parent.SubCode && o.Grade == grade).OrderBy(o => o.Order)) {
            var menu =new TreeMenu(){ TreeCode= child.MenuCode, TreeName=child.MenuName, Order=child.Order };
            treeParent.Children.Add(menu);
        }
        IterationMenu(source, ref treeParent, parent, grade + 1);
    } else {
        foreach (var child in treeParent.Children) {
            var child1 = child;
            child.Children = new List<TreeMenu>();
            foreach (var c in source.Where(o => o.SupMenuId == child.MenuCode && o.Grade == grade).OrderBy(o => o.Order)) {
                var menu = new TreeMenu() { TreeCode = c.MenuCode, TreeName = c.MenuName, Order = c.Order };
                child.Children.Add(menu);
            }
            IterationMenu(source, ref child1, parent, grade + 1);
        }
    }
}

WPF

Views

一个简单的左右布局用上TreeView和TabControl控件

TreeView

ItemsSource 绑定的是TreeMenu数据源，注意使用ObservableCollection

树形菜单使用HierarchicalDataTemplate进行数据迭代，

设计一个简单模板：

添加一个Grid布局实现多个控件
转换器BoolToVisible，将True转换Visibility.Visible，反之Visibility.Collapsed
转换器VisibleToReverse，将Visibility.Visible转换Visibility.Collapsed，反之Visibility.Visible
IsGrouping属性来判断子/父节点，父节点则用TextBlock显示本身，子节点就用Button来显示

<HierarchicalDataTemplate x:Key="TreeItemStyle" ItemsSource="{Binding Children}">
<Grid>
    <StackPanel x:Name="ParentMenu" Visibility="{Binding IsGrouping, Converter={StaticResource BoolToVisible}}">
        <TextBlock Text="{Binding MenuName}" />
    </StackPanel>
    <Button
        Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type TreeView}}, Path=DataContext.NavigateCommand}"
        CommandParameter="{Binding MenuCode}"
        Visibility="{Binding Visibility, ElementName=ParentMenu, Converter={StaticResource VisibleToReverse}}">
        <StackPanel>
            <TextBlock Text="{Binding MenuName}" />
        </StackPanel>
    </Button>
</Grid>
</HierarchicalDataTemplate>

<TreeView
    Grid.Column="0"
    ItemTemplate="{StaticResource TreeItemStyle}"
    ItemsSource="{Binding TreeMenuData}"/>

TabControl

这里用上了Prism的Regions实现控件的添加

<TabControl
    Grid.Column="1"
    prism:RegionManager.RegionName="TabRegion"/>

ViewModels

TreeView使用的模型

public class TreeMenu{
  public string TreeCode{get;set;}
  public string TreeName{get;set;}
  public string Order{get;set;}
  public bool IsGrouping{get{
    return (Children!=null&&Children.Count>0);
  }}
  public List<TreeMenu> Children{get;set;}
}

加载插件并与Prism关联

通过Prism的LoadModule加载插件，RequestNavigate进行导航请求

提示

Prism 加载 Module 有多种方式，但是这里因为一切都是动态可配，所以使用LoadManual的方式

private void LoadPrismModule(string menuCode){
    _moduleManager.LoadModule(menuCode);
    var parameters = new NavigationParameters{{ "code", menuCode }};
    _regionManager.RequestNavigate("TabRegion", menu.MenuId, parameters);
}

private readonly IConcurrentDictionary<string, Type> _compsCache = new ConcurrentDictionary<string, Type>();

private void LoadComponent(string menuCode){
    var link = DefautlLinks.FirstOrDefault(it => it.MenuCode == menuCode);
    if (link == null) return;
    Type? type = null;
    if (!_compsCache.ContainsKey(link.Assembly)){
        Assembly asm = Assembly.LoadFrom(AppDomain.CurrentDomain.BaseDirectory + link.Assembly + ".dll");
        type = asm.GetType(link.Class);
        if (type == null) return;
        _compsCache.Add(link.Assembly, type);
    } else {
        type = _compsCache[link.Assembly];
    }
    var moduleCatalog = _c.Resolve<IModuleCatalog>();
    moduleCatalog.AddModule(new ModuleInfo(){
        ModuleName = menuCode,
        ModuleType = type.AssemblyQualifiedName,
        InitializationMode = InitializationMode.WhenAvailable,
    });
    LoadModule(menuCode);
}

private void OpenTabItem(string menuCode){
    if (string.IsNullOrEmpty(menuCode)) return;
    var openMenu = DefaultMenus.FirstOrDefault(o => o.MenuId == menuCode);
    if (openMenu == null)return;
    var moduleExist = _moduleManager.ModuleExists(openMenu.MenuId);
    if (!moduleExist) {
        LoadComponent(openMenu);
    } else {
        LoadModule(openMenu);
    }
}

自定义插件

由于使用了Prism来实现插件化，那么自定义的项目也需要安装Prism

入口

项目名称为Demo.Plugin，自定义一个类继承IModule

public void RegisterTypes(IContainerRegistry containerRegistry) {
    containerRegistry.RegisterForNavigation<HelloView>("AA01");
    containerRegistry.RegisterForNavigation<WorldView>("SS010101");
}

自动更新

使用了更新功能，在启动时检查是否有新的DLL文件需要更新，如果有则更新，更新代码地址

结语

至此，一个基本的可配置化插件开发完成，稍微进行扩展就能实现更多功能

完整项目地址