When set a style for an Android custom layout it didn't work, but in Android Studio it works fine

[yorkvolvo]

Steps to Reproduce

1. Create a blank Xamarin.Android project.

2. Create a style in values\styles.xml:

   
   <resources>
   
   <style name="RelativeLayout2">
   <item name="android:layout_width">40dp</item>
   <item name="android:layout_height">300dp</item>
   <item name="android:background">#114499</item>
   <item name="android:padding">50dp</item>
   </style>

3. Create a custom layout file:

namespace CustomeView { public class RelativeLayout2 : RelativeLayout { public RelativeLayout2(Context context, IAttributeSet attributeSet) : base(context, attributeSet, 0, Resource.Style.RelativeLayout2) { } } }

4. Use it in android `activity_main.axml` file:

<?xml version="1.0" encoding="utf-8"?> <InflationWithStyle.RelativeLayout2 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" android:layout_width="match_parent" android:layout_height="match_parent">

<TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="An utter lack of style."/>

</InflationWithStyle.RelativeLayout2>

5. In `MainActivity.cs`:

[Activity(Label = "@string/app_name", Theme = "@style/AppTheme", MainLauncher = true)]
public class MainActivity : AppCompatActivity
{
    protected override void OnCreate(Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
        // Set our view from the "main" layout resource
        SetContentView(Resource.Layout.activity_main);
    }
}

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### Expected Behavior (When use these code in Android Studio)
![image](https://user-images.githubusercontent.com/18043540/45212274-0fe98b80-b2c7-11e8-973e-32ed970d295c.png)

### Actual Behavior(When use these code in Visual Studio)
![image](https://user-images.githubusercontent.com/18043540/45212346-40c9c080-b2c7-11e8-8737-bd3602972058.png)

## Question:

Could you please tell me that why defStyleRes has no effect in custom View (RelativeLayout)?

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[jonpryor]

Could you please attach both the Xamarin.Android project and the Android Studio projects?

I find this confusing, because neither the Styles and Themes documentation nor the Style resource documentation imply that the //style/@name value can be a View name and have things "magically linked". Instead, they both use a style attribute on the View, e.g.

<?xml version="1.0" encoding="utf-8"?>
<EditText
    style="@style/CustomText"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="Hello, World!" />

The original description does not use a style attribute in this manner.

[yorkvolvo]

@jonpryor ,

Code in Android Studio:

public class RelativeLayout2 extends RelativeLayout
{
        public RelativeLayout2(Context context, AttributeSet attributeSet)
        {
            super(context, attributeSet, 0, R.style.RelativeLayout2);
        }
}

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<com.example.testproject.RelativeLayout2
    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"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="An utter lack of style."/>

</com.example.testproject.RelativeLayout2>

[yorkvolvo]

@jonpryor I think problem is the line base(context, attributeSet, 0, Resource.Style.RelativeLayout2) didn't work.

I have searched a lot about android custom layout set style programmatically and found that we could set custom layout style like this:

public class RelativeLayout2 : RelativeLayout
    {
        public RelativeLayout2(Context context, IAttributeSet attributeSet)
            : base(context, attributeSet, 0, Resource.Style.RelativeLayout2)
        {
        }
    }

And it did works fine in Android Studio:

public class RelativeLayout2 extends RelativeLayout
{
        public RelativeLayout2(Context context, AttributeSet attributeSet)
        {
            super(context, attributeSet, 0, R.style.RelativeLayout2);
        }
}

But the same code in C# didn't work for Xamarin.Android, I wonder why this issue happened? Is this a bug of Xamarin.Android ?

If you have any problem when reproduce this issue, please feel free to contact me.

[jonathanpeppers]

@aixiaozi it would help a lot if you could make a quick sample project showing the problem and attach to this issue, thanks!

[grendello]

Since no requested info has been provided to-date, I'm going to close this issue. Please reopen if the requested information is available, thanks!