The type or name space does not exist...this error happens in the xaml.g.cs
that is here:
[global::Xamarin.Forms.Xaml.XamlFilePathAttribute("C:\\montana\\neoFly_Montana1\\neoFly_Montana\\neoFly_Montana\\PopUp\\LoginPopup.xaml")]
public partial class LoginPopup : global::Rg.Plugins.Popup.Pages.PopupPage {
[global::System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private global::Xamarin.Forms.Image login_img_forms;
[global::System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private global::Xamarin.Forms.StackLayout login_stack_forms;
[global::System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private global::Xamarin.Forms.MyEntry login_entry_login;
[global::System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private global::Xamarin.Forms.MyEntry login_entry_pass;
it happend after I changed the xaml file:
<?xml version="1.0" encoding="utf-8" ?>
<pages:PopupPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:neoFly_Montana.LayoutScripts"
xmlns:pages="clr-namespace:Rg.Plugins.Popup.Pages;assembly=Rg.Plugins.Popup"
xmlns:animations="clr-namespace:Rg.Plugins.Popup.Animations;assembly=Rg.Plugins.Popup"
x:Class="neoFly_Montana.PopUp.LoginPopup"
CloseWhenBackgroundIsClicked="False">
<MyEntry Placeholder="E-mail:" Margin="10,0,0,0" x:Name="login_entry_login" FontSize="Medium" TextColor="{StaticResource MarromClaro}" PlaceholderColor="{StaticResource MarromClaro}"/>
I added the MyEntry and the xmlns:local="clr-namespace:neoFly_Montana.LayoutScripts"
I tried to clean and rebuild solution
The compiler needs to know what MyEntry is - there are two steps to this. The first is to define the namespace, which you've already done. The second is to specify that MyEntry exists in the local namespace:
you need to use <local:MyEntry ...
Related
I'm trying to do a very common usage of Xamarin.Forms ListView, where I have multiple types of items.
I'm using a DataTemplateSelector and defining the different (two at this point) views in my XAML file. That requires referencing the c# code from the XAML code through a namesspace definition. And, that's where I'm stuck.
The error I'm getting is
XFC0000 Cannot resolve type "local:NodeTemplateSelector".
Here is my XAML, condensed:
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
...
xmlns:local="clr-namespace:varlist">
<ContentPage.Resources>
<ResourceDictionary>
<DataTemplate x:Key="NoteItem">
...
</DataTemplate>
<local:NodeTemplateSelector x:Key="NodeTemplateKey">
NoteTemplate = "{StaticResource NoteItem}"
ImageTemplate = "{StaticResource ImageItem}"
</local:NodeTemplateSelector>
</ResourceDictionary>
</ContentPage.Resources>
</ContentPage>
And, here is C#, also condensed:
namespace varlist
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class ListViewPage : ContentPage
{
...
public class NodeTemplateSelector : DataTemplateSelector
{
public DataTemplate NoteTemplate { get; set; }
public DataTemplate ImageTemplate { get; set; }
protected override DataTemplate OnSelectTemplate (object item, BindableObject container)
{
ListView list = (ListView)container;
if (item is NoteData)
return NoteTemplate;
else // item is ImageData
return ImageTemplate;
}
}
}
}
What do I need to change to get the XAML to recognize NodeTemplateSelector ?
As Jason and Shaw suggested, the NodeTemplateSelector must be in top level class.
Also, another problem I ran into is the syntax in the DataTemplate XAML file. Might as well add this note, in case anyone else has the same trouble:
The NodeTemplateSelector in XAML must be defined as direct content; must be like this:
<local:NodeTemplateSelector
x:Key="NodeTemplate"
NoteItemTemplate="{StaticResource NoteTemplate}"
ImageItemTemplate="{StaticResource ImageTemplate}"
/>
Otherwise you get a rather undecipherable runtime error.
If I need to post more code, then let me know, but I think what I have is sufficient to convey what I am trying to do. I can do it if I don't use XAML to define the page content, but when I try it with XAML, addng the <TViewModel,TDataModel> causes InitializeComponent() and any named elements in the XAML to get flagged as not found.
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class BaseSelectListPage<TViewModel,TDataModel> : ContentPage
where TViewModel : BaseSelectListViewModel<TDataModel>, new()
{
private TViewModel _viewModel { get; set; }
public BaseSelectListPopup()
{
_viewModel = new TViewModel();
BindingContext = _viewModel;
InitializeComponent(); // InitializeComponent gets flagged as not found
ExampleElement.Spacing = 5; // ExampleElement also gets flagged as not found
}
// rest of class
}
I don't know how to define the generic types in XAML, but here is what I tried.
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:d="http://xamarin.com/schemas/2014/forms/design"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Class="IRA.Views.SelectLists.BaseSelectListPage<TViewModel,TDataModel>">
<!-- this is obviously what I don't know how to do ^^^^ -->
<ContentPage.Content>
<StackLayout x:Name="ExampleElement">
<Label Text="Thanks for helping"/>
</StackLayout>
<!-- various elements -->
</ContentPage.Content>
</ContentPage>
I'm implementing a ListView in Xamarin.Forms with custom cells, but I can't see what I'm doing since the preview shows an empty list and re-building every time is simple too time consuming. I can't even see a simple TextCell..
How can I see the preview of my cells in the editor? This is my xaml:
<?xml version="1.0" encoding="utf-8"?>
<ContentPage
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:MyNamespace"
x:Class="MyNamespace.MyAppPage">
<ContentPage.Content>
<ListView x:Name="myList">
<ListView.ItemTemplate>
<DataTemplate>
<TextCell Text="Preview?" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ContentPage.Content>
Note: I am using Visual Studio 2017 for Mac.
2nd Part
OK so I tried using BindingContext but I don't understand well the usage of this property. This is my updated XAML:
<?xml version="1.0" encoding="utf-8"?>
<ContentPage
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:MyNamespace;assembly:MyNamespace"
BindingContext="{x:Static local:MusicSeed.Model}"
x:Class="MyNamespace.MyAppPage">
<ContentPage.Content>
<ListView ItemsSource="{Binding Tracks}">
<ListView.ItemTemplate>
<DataTemplate>
<TextCell Text="{Binding Name}" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ContentPage.Content>
</ContentPage>
And this is where I have the data, MusicSeed.cs:
namespace MyNamespace
{
public static class MusicSeed
{
public static readonly MusicSeedModel Model = new MusicSeedModel();
}
public class MusicSeedModel
{
public readonly MusicTrack[] Tracks =
{
new MusicTrack("Track 01"),
new MusicTrack("Track 02"),
new MusicTrack("Track 03"),
new MusicTrack("Track 04"),
};
}
}
The result is this error thrown by the XAML editor:
No static member found for local:MusicSeed.Model
I tried changing Tracks as static but nothing changed. Also rebuilt the solution, the error disappeared but the preview is still empty. What am I missing here?
You will have to provide some kind of BindingContext for rows to be rendered during design time. There is an awesome article by James Montemagno that explains how to do just that.
Another recommended article to refer would be this one on Xamarin Help
EDIT 1:
Your XAML is correct, but the view-model is wrong. You can only bind to properties. Try changing you declaration to following:
namespace MyNamespace
{
public class MusicSeed
{
public static MusicSeedModel Model { get; } = new MusicSeedModel();
}
public class MusicSeedModel
{
public MusicTrack[] Tracks { get; } =
{
new MusicTrack("Track 01"),
new MusicTrack("Track 02"),
new MusicTrack("Track 03"),
new MusicTrack("Track 04"),
};
}
public class MusicTrack
{
public string Name { get; }
public MusicTrack(string v)
{
this.Name = v;
}
}
}
You can't. If you are using MVVM framework, your code still needs to be generated / Build.
An Alternative is to use Xamarin Live Player Which Can Build Lists On your actual device for android and ios
FYI: Currently while answering this questions it's on Alpha
I would like to use new feature of UWP -> x:Bind. In order to that, all my pages need to have ViewModel property (as described in tutorials).
To avoid code duplicity, I have established base class as follows:
public abstract class BasePage<TBaseVM> : Page, where TBaseVM : BaseVM
{
public TBaseVM VM { get; private set; }
protected BasePage()
{
DataContextChanged += (s, e) => VM = e.NewValue as TBaseVM;
}
}
As you can see this BasePage class contains property called "VM" and property is of type BaseVM. Hence, I don't need to define VM property on each derived class.
Then I created derived page 'MainPage' defined in xaml as follows:
<pages:BasePage
x:Class="Realarm.View.Pages.MainPage"
x:TypeArguments="viewModel:MainVM">
By doing that, even Resharper's Intellisense offers me properties from "MainVM" in MainPage.xaml, thus is can write:
<ListView ItemsSource="{x:Bind VM.AlarmsVM}">
Unfortunately, when I try to build the project, I get error in MainPage.g.i.cs:
Severity Code Description Project File Line
Error CS0305 Using the generic type 'BasePage' requires 1 type arguments Realarm D:...\Realarm\obj\x86\Debug\View\Pages\MainPage.g.i.cs 13
Any help?
I got this working using Xamarin.Forms.
Base Page:
public abstract class BaseContentPage<TViewModel> : ContentPage where TViewModel : BaseViewModel, new()
HomePage.cs:
public partial class HomePage : BaseContentPage<HomeViewModel>
HomePage.xaml:
<d:BaseContentPage
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:d="clr-namespace:Sample.Pages;assembly=Sample"
xmlns:vm="clr-namespace:Sample.ViewModels;assembly=Sample"
x:Class="Sample.Pages.HomePage"
x:TypeArguments="vm:HomeViewModel">
<ContentPage.Content>
</ContentPage.Content>
</d:BaseContentPage>
Just add a x:TypeArguments definition at the top of the XAML:
<v:BasePage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:v="clr-namespace:YourApp.Views"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:d="http://xamarin.com/schemas/2014/forms/design"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:vm="clr-namespace:YourApp.ViewModels"
mc:Ignorable="d"
x:TypeArguments="vm:HomeViewModel"
x:Class="YourApp.MainPage">
Worked for me as well when I set the BindingContext as given below in Base Page's constructor:
public BasePage()
{
BindingContext = new TBaseVM();
}
I've seen examples of the "x:Static" expression being used to specify the ConverterParameter property of a binding in WPF XAML. However, as far as I can tell, Xamarin will not allow you to set the property in this way. Specifying the ConverterParameter in the code behind works fine, using a StaticResource expression works fine, using a literal value, fine. Could someone please point me to an example of this being done in Xamarin?
My XAML:
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="OMS.ProductionPickupPage"
xmlns:local="clr-namespace:OMS;assembly=OMS"
Title="Production Pickup"
Padding="5,5,5,5">
<ContentPage.Resources>
<ResourceDictionary>
<local:PickerIndexConverter x:Key="PickerConverter" />
</ResourceDictionary>
</ContentPage.Resources>
<!-- ... -->
<Picker x:Name="LoadingFacility_Picker" Title="Loading Facility" SelectedIndex="{Binding SelectedLoadingFacility, Mode=OneWayToSource,
Converter={StaticResource PickerConverter}, ConverterParameter={x:Static local:TestClass.TestMember}}" />
This is the exception thrown by the LoadFromXml method in InitializeComponent():
System.Exception: Property is not valid for this Expression
Stack Trace:
[External Code]
0xC in OMS.ProductionPickupPage.InitializeComponent at e:\Workspace\sumrallj\OMS\OMS\OMS\obj\Debug\ProductionPickupPage.xaml.g.cs:42,-1 C#
0x14 in OMS.ProductionPickupPage..ctor at e:\Workspace\sumrallj\OMS\OMS\OMS\ProductionPickupPage.xaml.cs:17,-1 C#
0x1 in OMS.App.GetMainPage at e:\Workspace\sumrallj\OMS\OMS\OMS\App.cs:14,-1 C#
0x22 in OMS.iOS.AppDelegate.FinishedLaunching at e:\Workspace\sumrallj\OMS\OMS\OMS.iOS\AppDelegate.cs:34,-1 C#
0xB in MonoTouch.UIKit.UIApplication.Main at /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:62,4 C#
0x3B in MonoTouch.UIKit.UIApplication.Main at /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:46,4 C#
0x8 in OMS.iOS.Application.Main at e:\Workspace\sumrallj\OMS\OMS\OMS.iOS\Main.cs:17,-1 C#
TestClass and TestMember are both static and I've also tried this with an enum.
namespace OMS
{
public static class TestClass
{
public static string TestMember = "Test";
}
}