I am setting command in my model as follow
Settings test = new Settings();
private Command _navigate;
public Command Navigate
{
set { SetProperty(ref _navigate, value); }
get { return _navigate; }
}
then I am adding it to my collection
private void LoadGeneralSetting()
{
foreach ( var setting in _customSettings.GeneralSettings )
{
var detail = new Settings()
{
Type = setting.Type,
Index = setting.Index,
IsSelected = setting.Value,
Navigate = new Command(GeneralSettingNavigation(null))
};
GeneralSetting.Add(detail);
}
}
and then the method
private void GeneralSettingNavigation(object sender)
{
Application.Current.MainPage.Navigation.PushAsync(new ThemeSelection());
}
however I am getting underline "Cannot resolve constructor 'Command(void)', candidates are: Command(System.Action) (in class Command) Command(System.Action) (in class Command)"
can you please advise what am I doing wrong I have tried null setting object.. just a string but still the same outcome
that's because the constructor for Command requires an Action, just like the error message is telling you
Navigate = new Command(() => { GeneralSettingNavigation(null); })
So basically I'm try to to find out if a page was pushed modally.
Here is the code I have for my extension method:
public static bool IsModal(this Page page)
{
return page.Navigation.ModalStack.Any(p => page == p);
}
The issue is; p never equals page due to the fact p changes to NavigationPage during runtime although intellisense reports it as a type of Page at compile time.
I've tried casting p to a Page but the type does not change at runtime and intellisense just moans that the cast is redundant.
I call this extension by using CurrentPage.IsModal in my View Model. CurrentPage is a type of Page at compile time but then changes to NavigationPage at runtime.
The confusing thing is that during debugging, p has properties such as CurrentPage and RootPage which show in the debugger, but these are not accessible by using p.CurrentPage as the compiler complains they don't exist !?! I was going to try an compare these but I can't access them but can view them in the debugger.
You need to check the type of page first, a page without navigationbar can also be pushed modally:
public partial class MainPage : ContentPage
{
public MainPage()
{
InitializeComponent();
}
private async void Button_Clicked(object sender, EventArgs e)
{
Page1 p = new Page1();
await this.Navigation.PushModalAsync(p, true);
bool b = PageExtensions.IsModal(p);
Console.WriteLine(b);
}
}
public static class PageExtensions
{
public static bool IsModal(this Page page)
{
if (page.GetType() == typeof(NavigationPage))
{
return page.Navigation.ModalStack.Any(p => ((NavigationPage)p).CurrentPage.Equals(page));
}
else
{
return page.Navigation.ModalStack.Any(p => p.Equals(page));
}
}
}
So this code works:
public static class PageExtensions
{
public static bool IsModal(this Page page)
{
return page.Navigation.ModalStack.Any(p=> ((NavigationPage) p).CurrentPage.Equals(page));
}
}
I'm concerned that is not safe as it assumes p is a Type of NavigationPage.
Can you try this, there could be typos, I wrote this freehand
public static bool IsModal(this Page page)
{
if (page.Navigation.ModalStack.Count > 0)
{
foreach (var thisPage in page.Navigation.ModalStack)
{
if (thisPage.Equals(page))
return true;
}
return false;
}
else
return false;
}
This is what I made to check the last pushed modal. Hope it helps to someone.
public async Task NewModalPagePushAsync(Page pageToOpen)
{
var lastModalPage = Application.Current.MainPage.Navigation.ModalStack;
if (lastModalPage.Count >= 1)
{
if (lastModalPage.Last().GetType().Name == pageToOpen.GetType().Name)
return;
}
await Application.Current.MainPage.Navigation.PushModalAsync(pageToOpen);
}
i need to redirect to another page in ViewModel after performing some action. I have button and set my command, however if i load the page fort the first time then i get an error "Please use navigation page" application fails and i start it again and try to load the page and it works, but if i delete the app from emulator and try all over again i have the same process.
public ICommand FilterItemsCommand { get; private set; }
public FilterArticlesForPurchaseViewModel()
: base()
{
Task.Run(async () => await LoadAllDataForArticlesAndCategories()).Wait();
FilterItemsCommand = new Command(async () => await FilterItems());
}
private async Task FilterItems()
{
await Application.Current.MainPage.Navigation.PushAsync(new ArticlesForPurchaseFiltered());
}
App
MainPage = new NavigationPage(GetMainPage());
I have also tried this
Application.Current.MainPage = new NavigationPage(new ArticlesForPurchaseFiltered());
But then i cant go back to previous page and if i use android back button the application fails
BTW i am using master detail
You can add INavigation navigation to your ViewModel's constructor like following code.
public ItemsViewModel(INavigation navigation)
{
Title = "Browse";
Items = new ObservableCollection<Item>();
LoadItemsCommand = new Command(async () => await ExecuteLoadItemsCommand());
FilterItemsCommand = new Command(() => { navigation.PushModalAsync(new Page1()); });
MessagingCenter.Subscribe<NewItemPage, Item>(this, "AddItem", async (obj, item) =>
{
var newItem = item as Item;
Items.Add(newItem);
await DataStore.AddItemAsync(newItem);
});
}
When you binding the viewmodel, you can add the attribute like following code.
public ItemsPage()
{
InitializeComponent();
BindingContext = viewModel = new ItemsViewModel(Navigation);
}
If you want to achieve the navigation in the viewModel, you can use
// this way you need add `MainPage =new NavigationPage( new MainPage());` in app.xaml.cs
navigation.PushAsync(new Page1());
// this way you do not need `MainPage =new NavigationPage( new MainPage());` in //app.xaml.cs, just used it directly
navigation.PushModalAsync(new Page1());
I have the following layout for my mvc project:
/Controllers
/Demo
/Demo/DemoArea1Controller
/Demo/DemoArea2Controller
etc...
/Views
/Demo
/Demo/DemoArea1/Index.aspx
/Demo/DemoArea2/Index.aspx
However, when I have this for DemoArea1Controller:
public class DemoArea1Controller : Controller
{
public ActionResult Index()
{
return View();
}
}
I get the "The view 'index' or its master could not be found" error, with the usual search locations.
How can I specify that controllers in the "Demo" namespace search in the "Demo" view subfolder?
You can easily extend the WebFormViewEngine to specify all the locations you want to look in:
public class CustomViewEngine : WebFormViewEngine
{
public CustomViewEngine()
{
var viewLocations = new[] {
"~/Views/{1}/{0}.aspx",
"~/Views/{1}/{0}.ascx",
"~/Views/Shared/{0}.aspx",
"~/Views/Shared/{0}.ascx",
"~/AnotherPath/Views/{0}.ascx"
// etc
};
this.PartialViewLocationFormats = viewLocations;
this.ViewLocationFormats = viewLocations;
}
}
Make sure you remember to register the view engine by modifying the Application_Start method in your Global.asax.cs
protected void Application_Start()
{
ViewEngines.Engines.Clear();
ViewEngines.Engines.Add(new CustomViewEngine());
}
Now in MVC 6 you can implement IViewLocationExpander interface without messing around with view engines:
public class MyViewLocationExpander : IViewLocationExpander
{
public void PopulateValues(ViewLocationExpanderContext context) {}
public IEnumerable<string> ExpandViewLocations(ViewLocationExpanderContext context, IEnumerable<string> viewLocations)
{
return new[]
{
"/AnotherPath/Views/{1}/{0}.cshtml",
"/AnotherPath/Views/Shared/{0}.cshtml"
}; // add `.Union(viewLocations)` to add default locations
}
}
where {0} is target view name, {1} - controller name and {2} - area name.
You can return your own list of locations, merge it with default viewLocations (.Union(viewLocations)) or just change them (viewLocations.Select(path => "/AnotherPath" + path)).
To register your custom view location expander in MVC, add next lines to ConfigureServices method in Startup.cs file:
public void ConfigureServices(IServiceCollection services)
{
services.Configure<RazorViewEngineOptions>(options =>
{
options.ViewLocationExpanders.Add(new MyViewLocationExpander());
});
}
There's actually a lot easier method than hardcoding the paths into your constructor. Below is an example of extending the Razor engine to add new paths. One thing I'm not entirely sure about is whether the paths you add here will be cached:
public class ExtendedRazorViewEngine : RazorViewEngine
{
public void AddViewLocationFormat(string paths)
{
List<string> existingPaths = new List<string>(ViewLocationFormats);
existingPaths.Add(paths);
ViewLocationFormats = existingPaths.ToArray();
}
public void AddPartialViewLocationFormat(string paths)
{
List<string> existingPaths = new List<string>(PartialViewLocationFormats);
existingPaths.Add(paths);
PartialViewLocationFormats = existingPaths.ToArray();
}
}
And your Global.asax.cs
protected void Application_Start()
{
ViewEngines.Engines.Clear();
ExtendedRazorViewEngine engine = new ExtendedRazorViewEngine();
engine.AddViewLocationFormat("~/MyThemes/{1}/{0}.cshtml");
engine.AddViewLocationFormat("~/MyThemes/{1}/{0}.vbhtml");
// Add a shared location too, as the lines above are controller specific
engine.AddPartialViewLocationFormat("~/MyThemes/{0}.cshtml");
engine.AddPartialViewLocationFormat("~/MyThemes/{0}.vbhtml");
ViewEngines.Engines.Add(engine);
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
}
One thing to note: your custom location will need the ViewStart.cshtml file in its root.
If you want just add new paths, you can add to the default view engines and spare some lines of code:
ViewEngines.Engines.Clear();
var razorEngine = new RazorViewEngine();
razorEngine.MasterLocationFormats = razorEngine.MasterLocationFormats
.Concat(new[] {
"~/custom/path/{0}.cshtml"
}).ToArray();
razorEngine.PartialViewLocationFormats = razorEngine.PartialViewLocationFormats
.Concat(new[] {
"~/custom/path/{1}/{0}.cshtml", // {1} = controller name
"~/custom/path/Shared/{0}.cshtml"
}).ToArray();
ViewEngines.Engines.Add(razorEngine);
The same applies to WebFormEngine
Instead of subclassing the RazorViewEngine, or replacing it outright, you can just alter existing RazorViewEngine's PartialViewLocationFormats property. This code goes in Application_Start:
System.Web.Mvc.RazorViewEngine rve = (RazorViewEngine)ViewEngines.Engines
.Where(e=>e.GetType()==typeof(RazorViewEngine))
.FirstOrDefault();
string[] additionalPartialViewLocations = new[] {
"~/Views/[YourCustomPathHere]"
};
if(rve!=null)
{
rve.PartialViewLocationFormats = rve.PartialViewLocationFormats
.Union( additionalPartialViewLocations )
.ToArray();
}
Last I checked, this requires you to build your own ViewEngine. I don't know if they made it easier in RC1 though.
The basic approach I used before the first RC was, in my own ViewEngine, to split the namespace of the controller and look for folders which matched the parts.
EDIT:
Went back and found the code. Here's the general idea.
public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName)
{
string ns = controllerContext.Controller.GetType().Namespace;
string controller = controllerContext.Controller.GetType().Name.Replace("Controller", "");
//try to find the view
string rel = "~/Views/" +
(
ns == baseControllerNamespace ? "" :
ns.Substring(baseControllerNamespace.Length + 1).Replace(".", "/") + "/"
)
+ controller;
string[] pathsToSearch = new string[]{
rel+"/"+viewName+".aspx",
rel+"/"+viewName+".ascx"
};
string viewPath = null;
foreach (var path in pathsToSearch)
{
if (this.VirtualPathProvider.FileExists(path))
{
viewPath = path;
break;
}
}
if (viewPath != null)
{
string masterPath = null;
//try find the master
if (!string.IsNullOrEmpty(masterName))
{
string[] masterPathsToSearch = new string[]{
rel+"/"+masterName+".master",
"~/Views/"+ controller +"/"+ masterName+".master",
"~/Views/Shared/"+ masterName+".master"
};
foreach (var path in masterPathsToSearch)
{
if (this.VirtualPathProvider.FileExists(path))
{
masterPath = path;
break;
}
}
}
if (string.IsNullOrEmpty(masterName) || masterPath != null)
{
return new ViewEngineResult(
this.CreateView(controllerContext, viewPath, masterPath), this);
}
}
//try default implementation
var result = base.FindView(controllerContext, viewName, masterName);
if (result.View == null)
{
//add the location searched
return new ViewEngineResult(pathsToSearch);
}
return result;
}
Try something like this:
private static void RegisterViewEngines(ICollection<IViewEngine> engines)
{
engines.Add(new WebFormViewEngine
{
MasterLocationFormats = new[] {"~/App/Views/Admin/{0}.master"},
PartialViewLocationFormats = new[] {"~/App/Views/Admin//{1}/{0}.ascx"},
ViewLocationFormats = new[] {"~/App/Views/Admin//{1}/{0}.aspx"}
});
}
protected void Application_Start()
{
RegisterViewEngines(ViewEngines.Engines);
}
Note: for ASP.NET MVC 2 they have additional location paths you will need to set for views in 'Areas'.
AreaViewLocationFormats
AreaPartialViewLocationFormats
AreaMasterLocationFormats
Creating a view engine for an Area is described on Phil's blog.
Note: This is for preview release 1 so is subject to change.
Most of the answers here, clear the existing locations by calling ViewEngines.Engines.Clear() and then add them back in again... there is no need to do this.
We can simply add the new locations to the existing ones, as shown below:
// note that the base class is RazorViewEngine, NOT WebFormViewEngine
public class ExpandedViewEngine : RazorViewEngine
{
public ExpandedViewEngine()
{
var customViewSubfolders = new[]
{
// {1} is conroller name, {0} is action name
"~/Areas/AreaName/Views/Subfolder1/{1}/{0}.cshtml",
"~/Areas/AreaName/Views/Subfolder1/Shared/{0}.cshtml"
};
var customPartialViewSubfolders = new[]
{
"~/Areas/MyAreaName/Views/Subfolder1/{1}/Partials/{0}.cshtml",
"~/Areas/MyAreaName/Views/Subfolder1/Shared/Partials/{0}.cshtml"
};
ViewLocationFormats = ViewLocationFormats.Union(customViewSubfolders).ToArray();
PartialViewLocationFormats = PartialViewLocationFormats.Union(customPartialViewSubfolders).ToArray();
// use the following if you want to extend the master locations
// MasterLocationFormats = MasterLocationFormats.Union(new[] { "new master location" }).ToArray();
}
}
Now you can configure your project to use the above RazorViewEngine in Global.asax:
protected void Application_Start()
{
ViewEngines.Engines.Add(new ExpandedViewEngine());
// more configurations
}
See this tutoral for more info.
I did it this way in MVC 5. I didn't want to clear the default locations.
Helper Class:
namespace ConKit.Helpers
{
public static class AppStartHelper
{
public static void AddConKitViewLocations()
{
// get engine
RazorViewEngine engine = ViewEngines.Engines.OfType<RazorViewEngine>().FirstOrDefault();
if (engine == null)
{
return;
}
// extend view locations
engine.ViewLocationFormats =
engine.ViewLocationFormats.Concat(new string[] {
"~/Views/ConKit/{1}/{0}.cshtml",
"~/Views/ConKit/{0}.cshtml"
}).ToArray();
// extend partial view locations
engine.PartialViewLocationFormats =
engine.PartialViewLocationFormats.Concat(new string[] {
"~/Views/ConKit/{0}.cshtml"
}).ToArray();
}
}
}
And then in Application_Start:
// Add ConKit View locations
ConKit.Helpers.AppStartHelper.AddConKitViewLocations();
I have the following ViewModel and I am using Caliburn Micro. The IWindowManager instance is properly resolved and all of the code works. As indicated by the TODO comment, I need to get a reference to the current window so I can toggle the AlwaysOnTop attribute. How can I do that?
namespace CaliburnWizardPlay
{
[Export(typeof(DropWindowViewModel))]
public class DropWindowViewModel : PropertyChangedBase, IHaveDisplayName
{
private readonly IWindowManager windowManager;
[ImportingConstructor]
public DropWindowViewModel(IWindowManager windowManager)
{
this.windowManager = windowManager;
}
public string DisplayName
{
get { return "Main Window"; }
set { }
}
public bool AlwaysOnTop
{
get { return Settings.Default.DropWindowAlwaysOnTop; }
set
{
Settings.Default.DropWindowAlwaysOnTop = value;
Settings.Default.Save();
NotifyOfPropertyChange(() => AlwaysOnTop);
//todo: toggle the AOT attribute of the window
}
}
public void FileDropped(DragEventArgs eventArgs)
{
if (eventArgs.Data.GetDataPresent(DataFormats.FileDrop))
{
string[] droppedFilePaths = eventArgs.Data.GetData(DataFormats.FileDrop, true) as string[];
foreach (string path in droppedFilePaths)
{
MessageBox.Show(path);
}
windowManager.ShowWindow(new WizardViewModel());
}
}
}
}
You can use the settings parameter of the ShowWindow method to set any property (e.g. Topmost) on the created window with a dictionary containing propertyname-value pairs:
windowManager.ShowWindow(new WizardViewModel(),
settings: new Dictionary<string,object> { {"Topmost", AlwaysOnTop} });
If you want to change the Topmost property of the already created window I see three options (in the order of preference):
Create an AlwaysOnTop property on the WizardViewModel and store the viewmodel in a private field and delegate the AlwaysOnTop to the WizardViewModel:
private WizardViewModel wizardViewModel;
public void FileDropped(DragEventArgs eventArgs)
{
//...
wizardViewModel = new WizardViewModel()
windowManager.ShowWindow(wizardViewModel);
}
public bool AlwaysOnTop
{
get { return Settings.Default.DropWindowAlwaysOnTop; }
set
{
//...
if (wizardViewModel != null)
wizardViewModel.AlwaysOnTop = value;
}
}
And in your view you can bind the WizardViewModel's AlwaysOnTop property to the window's TopMost property.
You can use the Application.Windows to retrieve the window. E.g. set the Name property of the created Window with the settings dictionary and then:
windowManager.ShowWindow(new WizardViewModel(),
settings: new Dictionary<string,object>
{ {"Topmost", AlwaysOnTop}, {"Name", "WizardWindow"} });
public bool AlwaysOnTop
{
get { return Settings.Default.DropWindowAlwaysOnTop; }
set
{
//...
var wizardViewModel = Application.Current.Windows.OfType<Window>()
.SingleOrDefault(w => w.Name == "WizardWindow");
if (wizardViewModel != null)
wizardViewModel.AlwaysOnTop = value;
}
}
Derive from the WindowManager and register it in your Bootstrapper and then you can override the CreateWindow, EnsureWindow etc. methods to store the created windows somewhere set the additional properties etc.