I am trying to work through the Caliburn.Micro Soup to Nuts tutorials using WPF rather than Silverlight.
In the "All About Actions" section of the Caliburn.Micro tutorial the following Silverlight code is shown in the overridden MefBootstrapper:
public class MefBootstrapper : BootstrapperBase
{
//same as before
protected override void OnStartup(object sender, StartupEventArgs e)
{
Application.RootVisual = new ShellView();
}
//same as before
}
With the comment "In this scenario, we simply override OnStartup, instantiate the view ourselves and set it as the RootVisual (or call Show in the case of WPF)."
Does anyone know what is the format of the Show command that is used? (I have tried a number of internet researched items but none worked). I'm guessing it must be very simple because of the casual mention in the tutorial...
Related
Relatively new to Xamarin, hitting an issue with PushAsync and navigation I can't figure out.
I have a main navigation page, and then a "MyContentPage" that is responsible for rendering a dynamic list based on a supplied id. When the user clicks on a list item they go to a next (newed up) "MyContentPage" (same class) with a different id. Basically a recursive page hierarchy based on a local db.
Problem is that navigation seems to quickly get messed up in some way I can't work out. The pages get swapped around, or get lost. Navigating back to root, if I click back down again, it skips to a page that is further down etc.
So basically the one page apart from the main page (which has multiple navigationpages in tabs - though I only use one tab at this point) binds its controls to this function:
public async Task NavigateToContent(int contentId)
{
await ((Application.Current.MainPage) as TabbedPage)?.CurrentPage.Navigation.PushAsync(new MyContentPage(contentId));
}
The above is then used recursively. Ie. Similar controls bind to the same function until there are no further pages to click down to.
The MyContentPage constructor loads the model:
public MyContentPage(int id)
{
InitializeComponent();
_id = id;
BindingContext = viewModel = new ContentPageViewModel(id);
}
What is the issue here?
From what you mentioned in comments, the issue is caused by the navigation code called in the 'service' class. When you call the service method multiple times, it actually changes the current navigation stack in xamarin forms. Move the page navigation code from service class to viewmodel class.
Or try to put the page navigation source code into something like 'NavigationService' (one example is the one in https://learn.microsoft.com/en-us/xamarin/xamarin-forms/enterprise-application-patterns/ ) and inject this service into your view model class.
OK so this all turned out to be an issue with concurrency.
The original button click was like this:
private void Button_Clicked(object sender, EventArgs e)
{
Task.Run(async () => await (BindingContext as ContentPageViewModel).ExecuteNavCommand(sender));
}
But this resulted in a UI operation happening on a different task
The event handler can be declared as async
The correction is
private async void Button_Clicked(object sender, EventArgs e)
{
await viewModel.ExecuteNavCommand(sender);
}
Introduction:
I am starting with code from:
https://github.com/xamarin/xamarin-forms-samples/tree/master/CustomRenderers/Entry/Android
to study custom renderers. I am doing this because there is code that only executes on the android platform. Lets call this "androidMethod()" and belongs in the Android codebase (not the shared library). I have noticed that most of the examples I have found have utilized customRenderers for making platform specific UI modifications (like the example in the link) but I intend to make no changes to the UI, rather I am trying to place a platform specific method in a Xamarin.Forms ButtonOnClick() method as the code below indicates.
The code below is similar to the code you will find in the MyEntryRenderer.cs from the link but you will see that it was modified to apply to a button instead of an entry.
MyButtonRenderer.cs:
using Xamarin.Forms.Platform.Android;
using Xamarin.Forms;
using CustomRenderer;
using CustomRenderer.Android;
using Android.Content;
[assembly: ExportRenderer(typeof(MyButton), typeof(MyButtonRenderer))]
namespace CustomRenderer.Android
{
class MyButtonRenderer : ButtonRenderer
{
private Button androidButton;
public MyButtonRenderer(Context context) : base(context)
{
}
protected override void OnElementChanged(ElementChangedEventArgs<Button> e)
{
base.OnElementChanged(e);
if (Control != null)
{
//I want to be able to do something like this:
ButtonOnClick(androidMethod());
}
}
}
}
How do I get androidMethod(); to execute in this context. The samples I find are limited so please try to limit your response to something that would be compatible with the example. Thankyou!
if you want to execute a platform specific method, I would use DepenencyService instead of a Custom Renderer
I have a window editor that holds nodes. I would like to open a custom inspector when one of these nodes is selected. The node class is a custom serializable class. Is this possible?.
It seems that custom inspectors can be created manually through the Editor.CreateEditor method but can't see how to let it appear docked like an usual inspector in the unity inspector window.
I would like to achieve the same behaviour that we have when we select a gameobject in sceneview that inmediately show properties for the object (Components, etc...) in the unity inspector.
Cheers
As I'm not sure what you're asking, here are multiple different solutions;
Selection
If you just want your nodes to become the focus of the hierarchy, then in your custom window's OnGUI method, use the code below;
[CustomEditor(typeof(NodeManager))]
public class NodeManager : EditorWindow
{
private static NodeManager window;
private Node[] m_nodes;
[MenuItem("Custom Windows/Node Inspector")]
public static void Init()
{
if(window == null)
window = GetWindow<NodeManager>("Node Manager", true, typeof(SceneView));
}
public void OnGUI()
{
m_nodes = GameObject.FindObjectsOfType<Node>();
foreach(Node node in m_nodes)
{
GUILayout.BeginHorizontal();
{
GUILayout.Label(node.name);
if (GUILayout.Button("Select"))
Selection.objects = new Object[] { node.gameObject };
}
GUILayout.EndHorizontal();
}
}
}
This adds a Button for each object in your custom window view, that will then select that object in the hierarchy.
Auto-Docking
I originally found the second response to this question, which goes into the details of parameters of the GetWindow method, and with this you can clearly see how to dock the window (I've converted it from JS to C# below).
(I looked fairly extensively in UnityEditor and UnityEditorInternal namespaces but couldn't find the Hierarchy or the Inspector).
GetWindow<T>(string title, bool focus, params System.Type[] desiredDockNextTo)
Which we can write for this example as;
EditorWindow.GetWindow<NodeInspector>("Node Test", true, typeof(SceneView));
This example docks the windows next to the SceneView window. This functionality can be combined with a custom inspector's OnInspectorGUI method, to automatically launch the custom node window, if it's not already open.
[CustomEditor(typeof(Node))]
public class NodeInspector : Editor
{
public override void OnInspectorGUI()
{
base.OnInspectorGUI();
NodeManager.Init();
}
}
Sorry if this isn't what you are looking for, if it's not then please give more details and I will amend my answer to better suit the question.
Hope this helped.
Has a possibility, you can make a custom ScriptableObject and Custom Editor for It, and when open the node inspector, just find a instance of the scriptable object and use Selection.selectedObject = scriptableObject, and in the custom editor, make a static field called 'editor' to draw inside.
It will work.
Our group is working on a Custom Activity Designer around our Email activity. It's a pretty straight forward designer, allow the user to enter settings / creds, but instead of cluttering the activity designer with all the settable options, we thought about putting some settings in a dialog window. (Which opens when you click the button beside the server address box).
Some of our email activity properties are InArguments so we are trying to make use of the ExpressionTextBox to display these values without much luck. The main problem is we aren't sure how to properly set up the binding and the OwnerActivity on the ExpressionTextBox. In the Activity Designer's xaml this is simply done by setting Expression=ModelItem.Property using a converter for the InArgument and setting the OwnerActivity=ModelItem, like this:
<view:ExpressionTextBox HintText="Enter a VB Expression" Expression="{Binding ModelItem.ServerAddress, ConverterParameter=In, Converter={StaticResource ArgumentToExpressionConverter}, Mode=TwoWay}" ExpressionType="{x:Type system:String}" OwnerActivity="{Binding ModelItem}" Margin="2" MaxLines="1" />
If anyone has any ideas on how we could accomplish this in a dialog, please advise.
Well, this is more a WPF\MVVM question than WF4, really.
When developing custom activities designers you just have to keep one thing in mind: any change made on designer\dialog should be reflected on ModelItem. Either through XAML binding expressions or through code on ModelItem.Properties property.
Now, when and how you do it, there are several answers to that but that's really an implementation detail and depends on how you want to do it.
Lets assume you're showing the dialog on button-beside-the-server-address-box click. And lets also assume you've access to dialog textboxes through their name. At that point, you've access to ModelItem so just set its properties as needed:
private void ButtonNextToServerAddressBox_OnClick(object sender, RoutedEventArgs e)
{
var dialog = new ServerAddressEditor();
var result = dialog.ShowDialog();
if (result ?? false)
{
ModelItem.Properties["Server"].SetValue(new InArgument<string>(dialog.ServerTextBox.Text));
ModelItem.Properties["Port"].SetValue(new InArgument<string>(dialog.PortTextBox.Text));
// ... set all other properties
}
}
Now, if you are using any other pattern, or you want pure MVVM, it can be a little more tricky because of how ModelItem works. But this is a totally fine approach.
I resolved this by creating a property in the dialog's ViewModel to hold the Activity Designer's ModelItem.
public ModelItem OwnerActivity {
get { return _OwnerActivity; }
set { _OwnerActivity = value; }
}
vm.OwnerActivity = this.DataContext.ModelItem;
I then set the Xaml for the Expression Text Box in my dialog to binding to this:
<view:ExpressionTextBox HintText="Enter a VB Expression" Expression="
{Binding Path=OwnerActivity.ServerAddress, ConverterParameter=In, Converter=
{StaticResource ArgumentToExpressionConverter}, Mode=TwoWay}" ExpressionType="
{x:Type system:String}" OwnerActivity="{Binding OwnerActivity}" Margin="2"
MaxLines="1" />
Because I'm now binding directly to the ModelItem from the Activity Designer, any change made to the ModelItem property from the dialog is ALWAYS committed, even if you choose to Cancel from the dialog. To wire up the Ok/Cancel buttons so they work accordingly, I did the following in the dialog:
// declare a ModelEditingScope to make changes transactional
private ModelEditingScope _editScope;
// add this to the constructor of the dialog to begin transactional edits on the ModelItem
_editScope = editorViewModel.OwnerActivity.BeginEdit();
// ok & cancel button click event to commit or revert the changes.
private void OK_Click(object sender, RoutedEventArgs e)
{
_editScope.Complete();
this.DialogResult = DialogResult.OK;
this.Close();
}
private void Cancel_Click(object sender, RoutedEventArgs e)
{
_editScope.Revert();
this.DialogResult = DialogResult.Cancel;
this.Close()
}
I'm trying to figure out how to successfully get Caliburn Micro to navigate from one page to another in a Windows Phone 8.1 app.
My first page loads just fine, as specified in my App class:
protected override void OnLaunched(LaunchActivatedEventArgs args)
{
this.DisplayRootViewFor<HomeViewModel>();
}
This launches the HomeView without issue. On that view I have a button that calls the following method:
public void GoToPage2()
{
this.navigationService.NavigateToViewModel<Page2ViewModel>();
}
This method is called when the button is pressed and the constructor for Page2ViewModel is called as well. The page just never displays and I can't figure out why. I feel like I'm missing a core concept, but I can't find any examples of how this should work.
Thanks for any help.
The solution is odd, and perhaps a bug in Caliburn Micro. In the OnLaunched method I used to have:
protected override void OnLaunched(LaunchActivatedEventArgs args)
{
this.DisplayRootViewFor<HomeViewModel>();
}
This worked and launched the home view, but subsequent navigation never worked. After comparing to a sample application I found, I changed the code to:
protected override void OnLaunched(LaunchActivatedEventArgs args)
{
this.DisplayRootView<HomeView>();
}
This also displays the home view, but now subsequent navigation works! I'm not sure why this would be the case, but at least I have an answer.