I'm using Visual Studio to try out Xamarin.Forms. I'm trying to follow the guide:
http://developer.xamarin.com/guides/cross-platform/xamarin-forms/xaml-for-xamarin-forms/getting_started_with_xaml/
In short, I create a Xamarin.Forms solution using a PCL and then try to add a Forms XAML Page to the PCL-project.
The code-behind that gets created looks like this:
public partial class Page1 : ContentPage
{
public Page1()
{
InitializeComponent();
}
}
The problem here is that InitializeComponent(); is red.
When I try to build I get informed that The name 'InitializeComponent' does not exist in the current context
I've been looking around for solutions and even though others have had the same trouble, their solutions wont work for me. Here is one suggestion i tried to use:
http://blog.falafel.com/xamarin-error-initializecomponent-does-not-exist-in-the-current-context/
Please let me know if you have a solution for this problem. Thanks!
Update:
My PCL (which is where I also want to add my XAML-page) contains:
App.cs:
public class App : Application
{
public App()
{
// The root page of your application
MainPage = new ContentPage
{
Content = new StackLayout
{
VerticalOptions = LayoutOptions.Center,
Children = {
new Label {
XAlign = TextAlignment.Center,
Text = "Welcome to Xamarin Forms!"
}
}
}
};
}
protected override void OnStart()
{
// Handle when your app starts
}
protected override void OnSleep()
{
// Handle when your app sleeps
}
protected override void OnResume()
{
// Handle when your app resumes
}
}
And my XAML-page:
<?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="XamaTest.MyXamlPage">
<Label Text="{Binding MainText}" VerticalOptions="Center" HorizontalOptions="Center" />
</ContentPage>
Code-behind:
public partial class MyXamlPage : ContentPage
{
public MyXamlPage()
{
InitializeComponent();
}
}
UPDATE:
This error doesn't usually appear in VS 2015, if it does, here's my original answer:
Found the solution!
Right click on the .XAML file, select Properties.
You will see a Property called Custom Tool. Change its value from MSBuild:Compile to MSBuild:UpdateDesignTimeXaml
This will solve the problem.
Dont know about the downvote, but here's my screenshot:
UPDATE:
It reappears rarely. If it does, just open the Xaml and code behind files and save them. I know, its not the best solution, but it gets the job done.
I get this sometimes and here's the checklist that solved them so far:
Make sure the namespace in .xaml and .xaml.cs match
Inherit from the correct parent - ContentPage for a page and ContentView for a control
Set build action of the .xaml file to Embedded Resource if in the shared project.
As far as my observation is concerned, in Visual Studio 2015, XAML properties are already set as suggested by highly-voted answers here by default, specifically :
Custom Tool = MSBuild:UpdateDesignTimeXaml
Build Action = Embedded Resource
but the error still appears sometimes... (like in this other question).
Editing the corresponding XAML file and then hit CTRL+S should work fine, but you don't have to. A cleaner way to force Custom Tools to be run is by right-clicking on the XAML file and then click on "Run Custom Tool" context menu.
I have met this problem. It's associated with the encoding of XAML files in VS. I'm using VS2015.
I solved this problem as follows:
Open the *.xaml file in the project and click Save button. (There will be applying the correct encoding in VS2015).
Then reopen the project and rebuild it. Now there are no errors.
Updating the Xamarin.Forms NuGet package should do the job
This is probably not your case but I had similar problem and mine was xaml and code behind name missmatching. for example according to your sample,
if code behind namespace is XamaTest(name of your app in most cases) and class is called MyXamlPage, your xaml class name must be XamaTest.MyXamlPage ([namespace].[classname])
I was silly after creating an empty xaml with code behind, I changed name of the class in xaml and i was getting this error.
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="XamaTest.MyXamlPage">
<Label Text="{Binding MainText}" VerticalOptions="Center" HorizontalOptions="Center" />
</ContentPage>
Code-behind:
public partial class MyXamlPage : ContentPage
Try adding a x:Name="..." on the xaml page... Nothing else worked for me - but after adding the x:Name attribute on some of the elements on the page the error dissapeared (most of the times - I still get it sometimes). I use the latest build (1.5.0.6447) of Xamarin.Forms...
XAML don't work on shared projects - it only works in portable projects...
It looks like the (re)generation of the blah.xaml.g.cs files is actually the problem. I get this a LOT in shared projects (which is why I don't use them unless I have no other choice). It happens way more in Xamarin Studio than Visual Studio, for me, for some reason. I try not to use XS at all.
Often unloading one of the other platforms (e.g. if you're building droid, unload ios) and doing a clean and rebuild will fix it.
You can also try doing something like opening one of the offending .xaml files and changing some of the xaml markup (e.g. adding or changing an x:Name to one of the controls or views). This will force a regeneration of the xaml.g.cs file, and (for me at least) usually solves the problem.
This really shouldn't be a thing tho.
I came across this error when;
I removed a ContentPage-cs+xaml and the App-cs+xaml from the project without actually deleting it.
Re-added these to the project in another folder.
This was fixed by;
Select the .xaml file of the class in which the issue is present.
Right click and select properties.
In Build action select "Embedded Resource"
In Custom Tool type "MSBuild:UpdateDesignTimeXaml"
Clean and Build and it was gone.
Check page text x:Class="AppName.Page1". AppName must be your app name
If you get intellisense errors such InitializeComponent in your Xamarin.Forms pages but the project actually builds and runs fine, just add a new Forms page using the wizard to fix all errors...
Then you can delete that new page.
I had similar problem in Visual Studio 2013 update 4 environment and I tried all recommendations what I found on the web. Nothing solved my problem.
Then I tried workaround approach. I installed Visual Studio 2015 preview and create new blank app with xamarin forms project.
When I added new Xaml file everything was OK and issue with InitialComponent method disappeared.
I don t know where exactly is the reason of the problem but it seems to be issue around configuration settings.
A Clean and rebuild did the trick for me!
Right click *.xaml and click properties,and change "Custom Tool" value to "MSBuild:UpdateDesignTimeXaml", next change "Build Action" properties to "Embedded Resource",
build project works.
Very simple solution that worked for me:
Copy contents of the xaml/cs file
Delete the xaml/cs file
Create a new class and paste the contents
Now the InitializeComponent() function appears without red underline.
Hope this helps someone.
Check the class name properly.
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="{AppName}.{ClassName}">
</ContentPage>
The class name should be a combination of App name and partial class name
This problem appears when the projects of solution are referencing the version 1.4.0.0 of the dlls "Xamarin.Forms.Core", "Xamarin.Forms.Xaml" and "Xamarin.Forms.Platform" version 1.0.0.0.
To solve it I've had to downgrade to version 1.3.3.0 of the dlls but with this version Xamarin.Forms.Platform 1.0.0.0 don't exists.
Check the version of Xamarin.Forms package referenced in your project.
I have been having the same issue now and then, and this is what I have been doing to fix it: When in the PCL project, I add a new cross-platform XAML page to the project. Adding a new XAML page takes a few seconds for the references to "hook". After the new XAML page is successfully added to the project, the red underlines on the XAML Pages (with issues) will get cleared. Once the problem is solved, I simply delete the XAML file that I have just added. - So, in summary, adding a new XAML page then deleting it has been solving the issue for me.
I Just updated All packages, works fine.
Change Page properties to :
BuildAction => Embedded resource
CustomTools => MSBuild:UpdateDesignTimeXaml
I had a caching issue when I encountered this error.
To get this fixed, simply uninstall last version of Xamarin.Forms package and reinstall a previous working version.
When the rebuild is successful, then update the package again to the latest version.
It appears this is caused by many things so if you've read all of these and haven't resolved it yet:
Mine was caused by the Solution Configuration being set to Release. Changed to Debug and error resolved.
In my case the problem was the project path.
The generated code file gets a name including the absolute path encoded to make it a valid filename.
The path was "D:\Projekt C#\ProjectRootFolder\Project".
The filename generated by the build tool was "Project.Droid.D_.Projekt_C_. Namespace etc."
Moving the project to a path like "D:\project\ProjectRootFolder" helped in my case.
I'm using Visual Studio 2015, I got the same problem, and found none of the answers on the net was a full solution.
Here I'll explain what worked for me.
My primary goal here was to eliminate the red error message that kept coming up
The name InitializeComponent does not exist in the current context
Basically I created a function called InitializeComponent2() that does exactly the same thing as InitializeComponent() and used that instead, I literally copied the code for InitializeComponent().
Does the job.
It looks like this (and I'll explain):
[System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private void InitializeComponent2()
{
// Change to:
// this.LoadFromXaml(typeof(Page2)); // for Page2
// this.LoadFromXaml(typeof(Page3)); // for Page3
// and put
// using Xamarin.Forms.Xaml;
// at the top of each source file.
this.LoadFromXaml(typeof(Page1));
}
Put the function in the definition of each of your pages (.cs files) e.g.
public partial class Page1 : ContentPage
{
[System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private void InitializeComponent2()
{
// Change to:
// this.LoadFromXaml(typeof(Page2)); // for Page2
// this.LoadFromXaml(typeof(Page3)); // for Page3
// and put
// using Xamarin.Forms.Xaml;
// at the top of each source file.
this.LoadFromXaml(typeof(Page1));
}
}
Also you need to put using Xamarin.Forms.Xaml; at the top of each .cs page
where LoadFromXaml(..) is used.
And then of course change InitializeComponent() to
InitializeComponent2() to call the new function.
i.e. you have put the function into the same context as the page making the error go away. I can't imagine the real InitializeComponent function will get anything added to it as you modify your project but that is a possibility.
It's been fine for me so far.
I tried many things, changing the Build Action, the XAML namespace, restarting vs, cleaning+rebuilding, looking for NuGet package updates.
Basically, Visual Studio compiled and ran the program fine on my android device + emulator, but that error message wouldn't go away.
My solution is for Android, but it may also work for iOS etc.
I went back to the root of the problem InitializeComponent() The actual code for this function is generated in a file called <Your Project Name>.Page1.xaml.g.cs or Page2.xaml.g.cs for example. However, it (the file) is
only generated when a certain event gets fired. I was lucky to discover
it by typing text into "Custom Tool Namespace", which fired that event, for one of the xaml pages(a file ending in .xaml, not .cs - make sure you have .xaml file selected), type some text and press enter and the file will be created.
Then I had the great idea of making InitializeComponent2(), a function exactly the same as InitializeComponent() and putting it in each cs file so it exists
without having to generate the .xaml.g.cs every time you want the error to
go away.
I don't know if this is solved, but for me, the only thing I had to do is remove the first line of the XAML ("xml version="1.0" encoding="utf-8")
Sometimes source version control, tries to identify which type of file is and add this kind of stuff.
add using Xamarin.Forms.Xaml
tested on Visual Studio 2017
Select the App.xaml and MainPage.xaml file of the class in which the issue is present.
Right click and select properties.
In Build action select "Embedded Resource"
In Custom Tool type "MSBuild:UpdateDesignTimeXaml"
Clean and Build and it was gone.
Ultimate solution would be to edit the project file in a text editor and just copy the pattern from another non-conflicting file. This solution worked for me. Usually, you would look for this syntax:
<Compile Update="Your\Path\YourContentPage.xaml.cs">
<DependentUpon>YourContentPage.xaml</DependentUpon>
</Compile>
In Xaml Page Properties only set
Build Action = Embedded resource
It works in visual studio 2017.
I started a vanilla master detail project with swift. If I add a new view controller and set the custom class, then the modules list is empty and it is not possible to choose a module. The error message "Unknown class in Interface Builder file." appears in the console if I run the code.
How can I setup the storyboard to know the custom class and module?
How it should be. The two classes from the template are just fine.
and how it is
I have to add customModule="Target_Name" customModuleProvider="target" to the interface builder source code. That is really annoying!
Update:
If I move the whole project directory to another, e.g. to the desktop it works. Looks like my directory with the name "Repository" is broken. Don't know why :(
I used to encounter the same issue, I finally found that the StoryBoard's Target Membership has been set incorrectly
.
I was getting the same problem but I discovered that I had inadvertently assigned a non-existing custom class to the view object managed by my view controller. So in the storyboard document view, I selected the badly configured view object, then in the identity inspector, deleted the bad custom class displayed for it (by backspacing and hitting return). That took care of the problem.
In my case, the custom class should be assigned to to the view controller, and not the view object managed by the controller.
I hit a similar issue when I changed the default Xcode project's UIViewController subclass to instead be a subclass of UITableViewController. (I made this change in the class source file, nothing to do with Storyboard).
I then went and typed my new class name into the IB "Class" field of the default "view" in the Storyboard. It would not autocomplete my class name, and then gave the Unknown class in Interface Builder file error when run.
The solution was to delete the default UIViewController object from the Storyboard, then add a new UITableViewController. Then, set that object's Class in IB to be your custom class.
It seems like the original question may be hitting this issue, as the first screenshot's class is ...ViewController and the second is ...TableViewController.
I've encountered the same issue and got it fixed. Reading this question gave me an idea to check the Identity Inspector further more and I found that the class Module should be inherit from target instead from a None module as I had.
Try checking the Inherit Module From Target checkbox and rebuild.
Hope it can help someone, obviously your problem has been solved since it was published in 2014.
I've looked here and here to try to answer this question as well as a billion Google searches, but have yet to come up with a solution.
My directory structure is a multi-tenant MVC site with an overridden view engine that uses Areas to serve content for different hosts that share a lot of common logic served globally from the base controllers and views folders. We have taken this a step further and broken out different global site sections into a new folder called SiteSections. Inside of this folder we have more Areas.
The issue I am having, is whenever I try to use the visual studio context menu from inside a controller that is inside the SiteSections folder, it always adds it to the global Views folder.
What I am assuming is happening is that since these are Areas held within a different directory, Visual Studio is searching the Areas folder for an Area with the name of which I am working in. Since this is kept in a different directory, it is just defaulting to the global one. I've looked into all the different T4 templates and do not see anything specifying the directory where the view will be created.
I have just one question, that I'm hoping is possible.
How can I override Visual Studio to look in a second directory for the Area in question?
Thanks in advance!
I experienced something like that, not with Areas, but with Folders.
Have you tried to add custom view engine on ViewEngines?
The steps that i followed:
1 - I put this line at Global.asax.cs on method Application_Start:
ViewsEngines.Engines.Add(new MyCustomViewEngine());
2 - I created the file named as MyCustomViewEngine inheriting from RazorViewEngine, for example:
public class MyCustomViewEngine : RazorViewEngine
{
public MyCustomViewEngine()
{
base.ViewLocationFormats = MyViewLocationFormats;
}
private static string[] MyViewLocationFormats = new[]
{
"~/Views/Folder/{0}.cshtml",
"~/Views/Folder_1/Folder_2/{0}.cshtml"
}
}
I think that you can use in this way: "~/Areas/Views/Folder/{0}.cshtml",
Hope this helps!
I have made a custom control (round button with a fixed image) and tested that it works. However, I would like to reuse this particular control in other projects and hence thought of making a class library out of it. However, when I try to get the custom control to show in my other applications, the icons does not show even though the button responds to clicks.
I have tried to build the icon in the class library projects as Content and Resources and test but to no avail. (of course, I change the addressing of the icon in the code when I updated its build icon). At the moment, i have decided to leave the icon /icons/myimage.png to be built as Content. And, in the class library code (XAML), i am accessing it as "/icons/myimage.png".
So, would anyone have an idea on how I could get the round button to render properly in my projects? How should I build the class library project?
I would't make a graphics part of my class library, because most likely in the future you will need to customize it, so what I suggest is to make the following property in your custom module and set the image where you use it:
public ImageSource ButtonImage {get { return <button image>; } set { <set button image>; } }
I experimented a bit and found the solution. The idea is to use embedded resource to store the image in the dll. And then for loading it by the CustomControl, one can use constructs like this:
BitmapImage img = new BitmapImage();
img.SetSource(Assembly.GetExecutingAssembly().GetManifestResourceStream("MyLib.icons.my_icon.png"));
MyLib here is the name of the assembly for the class library. icons is the folder where the resource is kept in the assembly.
I have the following file: Foo.cs with a Foo class inside of it. I can't seem to find the right way to keep my resource files (resx) organized behind their respective files.
If I create a Foo.resx the resource file gets folded away nice and tidy behind the Foo.cs class. This, however, causes issues because the standard custom-tool that generates the code attempts to create another Foo class (Look at the Foo.Designer.cs: internal class Foo { ... }). If my Foo.cs file does not already contain a Foo class, this works fine (no naming collision).
To fix the naming collision I attempted to give it a custom namespace MyProj.Resources and use an alias to identify it: using R = MyProj.Resources.Foo; This still causes issues because the auto-generator has an issue creating a ResourceManager properly.
If I, instead, name it something along the lines of FooResx.resx it does not automatically get folded behind the Foo.cs file. Instead, it resides in the solution explorer right below it. Going into the MSBuild (.csproj) file and adding a <DependentUpon> tag, then Visual Studio neatly tucks away my FooResx.resx file. However, I can't actually use any of the resources from that file because the auto-generated code has an issue creating a ResourceManager properly.
Basically, is there any way to have the Resource files (resx) fold behind a cs file and still work properly using the standard Custom Tool (ResXFileCodeGenerator)?
I do realize that I can always place all my resources into a file within the properties folder: resources.resx. I'm trying to organize them better than that though.
Update:
I decided to manually edit the auto-generated code and make it partial. This allowed the code to compile, but I still ran into the same issue (Issue #2). It seems that if a resource file is folded behind (manually or automatically) another code file then the ResourceManager has trouble finding the *.resource file. This might be an issue I'll have to raise with Microsoft Connect about the ResXFileCodeGenerator tool. It needs to be able to locate the proper *.resource file when folded behind other files.
The solution could be to make your classes and your generated code partial classes - if you look at a .Designer.cs (from a System.Windows.Forms.Form for example) you will discover that it declares something like partial class Foo.
Foo.cs
public partial class Foo
{
}
Foo.Designer.cs
partial class Foo
{
}
Edit
It turns out that StronglyTypedResourceBuilder or PublicResXFileCodeGenerator insists on generating classes with either internal or public access modifier (it can be set in the .resx).
Setting ResXFileCodeGenerator as the CustomTool in the properties of your .resx still doesn't give you the behaviour you'd see in a generated .Desinger.cs of a Form.