Visual Studio 2015 - Xamarin - Android - Getting "resource.id does not contain a definition for xxx" when I try to do anything in the .cs file

Question

Adding Additional Activity .cs and Layout axml Using Visual Studio 2015.

I'm very new to Xamarin and Android development, but have been a developer for a few years using VB and now C#. I have a simple app on Android 4.2 that is getting more complicated as I go along. The simple matter us that I want to add an additional GpsAction.cs and corresponding Gps.axml layout to the project. It seems impossible to find the right combination syntax to achive this. I have a mainActivity with main.axml. In VS 2015 it's very simple to add new but I keep getting "resource.id does not contain a definition for" I would really appreciate your help with this

namespace AddCam
{
[Activity(Label = "GpsActivity")]
public class GpsActivity : Activity
{
    protected override void OnCreate(Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
        SetContentView(Resource.Layout.GpsLayout);

        string c = FindViewById<TextView>(**Resource.Id.textView1**).Text;
        // Create your application here
    }
}

Xamarin is notoriously buggy, especially with layouts. Do a full rebuild and see if that helps. — Sami Kuhmonen, Mar 12 '16 at 07:15
You are correct Sami, I was doing cleans and rebuilds over and over. So this morning I logged on and low and behold I had no error. So now I'm crazy with curiosity and have to find out what I did right. Turns out that if I changed the text field "id" saved, rebuilt and changed it back it fixed it. I'm marking your answer correct. Thanks a bunch - misery loves company — RobertM - Orlando, Mar 12 '16 at 21:15
Gusman- I should have added the axml in the original. Before I realized it I had over written the original with attempts to fix it. I stared at it for a long time and it was correctly appearing that was the mystery and the exact same code was working in another app this was literally a cut and paste. But next time I will post the axml regardless. Thanks for the response. — RobertM - Orlando, Mar 13 '16 at 16:13
I had one where the problem was an invalid XML syntax: a . (dot) somewhere after a closing /> . As there was no message about it, and a . is barely visible ........ it takes tome to find it. — Martin, Jan 13 '19 at 15:25

Ram Iyer · Answer 1 · 2017-05-11T12:53:56.070

8

For people who are still facing this issue, the default Build Action of the layout file would be set to TransformFile. Select the layout, go to the Layout Properties, and in the properties pane, Select AndroidResource as your Build Action. Clean build your project and it should work.

edited May 11 '17 at 12:53

answered May 11 '17 at 06:57

Ram Iyer

1,621
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score 7 · Answer 2 · edited Aug 07 '19 at 13:29

I changed the text field "id" from "@+id/imageView1" to "1", saved, rebuilt and changed it back to "@+id/imageView1", it fixed it. I would like to add, this whole problem came from

Adding a new activity and layout.
Using preexisting code from another app that I had.
Copying and pasting code from the original app to the new Activity and Layout.

All fairly common stuff, the real problem seemed always to be adding any new Activities and Layouts to a main Activity. It can get very convoluted and with no (known to me) logical way to run down a problem with Xamarin. Don't get me wrong compared to 10 years ago (the last mobile app I tried to write) Xamarin is heaven. Good coding folks, now if I can only figure out why Keyword "this" is error-ring on the added Activity.cs

score 4 · Answer 3 · answered Oct 17 '16 at 12:23

4

Just add namespace like that Android.Resource.Id - it's resolve for me

answered Oct 17 '16 at 12:23

Serhii Horun

41
1

Thank you a lot! I've just added `public partial class Id { }` inside class Resource and rebuilt the project. Now all `Resource.Id.____` works well – Pavel Apr 24 '17 at 11:24
This one, done along with clean rebuild *and* [RoberM's answer](https://stackoverflow.com/a/35963477/479251) did the work. VS 2017 + Xamarin Forms 3.6.0 – Pac0 Jun 05 '19 at 09:27

score 3 · Answer 4 · answered Jul 19 '18 at 18:01

3

What did work for me (Visual Studio 2017, opening an old Xamarin project):

Delete obj and bin folders, build.
If errors, restart Visual Studio (I know the pain).
Build again

Now the Resource will be visible (of course, if you defined it correctly).

answered Jul 19 '18 at 18:01

Exel Gamboa

936
1
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score 1 · Answer 5 · edited Jun 21 '17 at 23:13

1

The best solution I have found is to build solution. Choose Build solution from Build menu (or Ctrl+Shift+B). This action will resolve the issue.

edited Jun 21 '17 at 23:13

mx0

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answered Jun 21 '17 at 04:49

Slackgate

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score 1 · Answer 6 · answered Sep 23 '17 at 08:09

1

You Should add set value forandroid:id="@+id/button1" in axml of app, then rebuild the project and try again. like thisButton button = (Button)FindViewById(Resource.Id.button1); .

answered Sep 23 '17 at 08:09

PL_Pathum

173
1
11

score 1 · Answer 7 · answered Dec 10 '18 at 14:24

1

Check if you are missing these namespaces in your layout file -

xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"

answered Dec 10 '18 at 14:24

Rupam Das

373
9
19

score 0 · Answer 8 · answered Mar 11 '17 at 01:56

0

Cleared Main.axml page and Reset and it is working.

answered Mar 11 '17 at 01:56

Arun Prasad E S

9,489
8
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score 0 · Answer 9 · answered Sep 08 '18 at 17:18

0

My problem was I was trying to debug Xamarin Android project (native) using Xamarin Live Player, connecting using USB cable and selecting my device for debugging solved the problem

answered Sep 08 '18 at 17:18

mohas

1,911
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score 0 · Answer 10 · answered Apr 13 '19 at 10:57

0

Make sure your axml is well formed and rebuild the solution it should work, if you continue facing the same issue then remove axml and add it again then build the solution.

answered Apr 13 '19 at 10:57

Saravanan

1

score 0 · Answer 11 · answered Aug 08 '19 at 19:03

In Visual Studio 2019 when you add a new Android Layout to the Project it is added as .xml file. I already had some created earlier layouts in Resources/layout folder with extension .axml (not .xml) and for me changing the extension .xml -> .axml worked.

score 0 · Answer 12 · answered Sep 01 '19 at 22:14

I understand that this issue is very old, but I've run into it as well in Visual Studio 2019, and have found a solution.

The issue occurs, for me, when adding an element to the layout and then attempting to add code. The issue appears to be related to the way the project is built.

Add the element to your layout, then build your project before adding any additional code. Apparently Resource.Id does not update with additional members until it's built, and attempting to refer to the new member in the code before Resource.Id recognizes it prevents the project from being built.

score 0 · Answer 13 · answered Sep 07 '19 at 14:25

0

Like Maniacz said, in VS 2019 I just had to change the XML to axml extensión to the layout in layout folder under resources

answered Sep 07 '19 at 14:25

Erick Mendoza Padilla

1
1

score 0 · Answer 14 · answered Oct 04 '19 at 13:25

For anyone else looking for an answer despite running clean/build/rebuild which didn't work for me:

I had freshly installed a number of tools for xamarin development in VS. Though a build/rebuild may have actually worked, in my case I believe what also fixed it was closing and re-opening VS. I'm pretty sure I had a few issues, primarily stemming from newly installed tools (android SDKs in my case) requiring VS to be restarted. If you're working on a project already having installed the tools you need, try as others have said - build/rebuild.

Ebrahim ElSayed · Accepted Answer · 2020-01-23T16:39:03.367

0

(VS 2019) I did the previous solutions and nothing, I had the same problem and the solution for me was to remove '&' from the text of TextView, I was trying to Set the text to "text&text" even &&(I though it was like mnemonics as in WindowsForms) didn't work so I had to remove it and it fixed.

edited Jan 23 '20 at 16:39

answered Jan 23 '20 at 16:32

Ebrahim ElSayed

157
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score 0 · Answer 16 · answered Dec 04 '20 at 00:00

I had to modify Build Action for my layout file and re set the original Build Action as it was previously set. This made my visual studio to regenerate the resource ids in Resource.designer.cs file.

Step #1:
Go to properties of the layout file that is missing its ids and click the Build Action DropDown.

Step #2:
Select something from the dropdown other than AndroidResource.

Step #3:
Reselect AndroidResource from that Build Action.

Now, you will have your Resource.designer.cs file regenerated and it will have the reference ids to your controls in the layout file.

score -1 · Answer 17 · answered Jun 17 '18 at 12:36

-1

Check the Resource.Designer class file. There will be a class like public partial class Id. There the integer IDs of the controls are written. Use them instead of Resource.Id

answered Jun 17 '18 at 12:36

Assasin Dentes

1

1

really bad advise. The Designer class was designed to prevent manually entering IDs – Zun Jun 18 '18 at 14:43
Well, then one should remember SAVING the main.axml file before moving to the .cs file. That's what I found though :p – Assasin Dentes Jul 29 '18 at 13:35

Visual Studio 2015 - Xamarin - Android - Getting "resource.id does not contain a definition for xxx" when I try to do anything in the .cs file

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