monodroid/xamarin custom attributes are empty using ObtainStyledAttributes

Question

Trying to pass a custom attribute from a parent layout to a child layout. The TypedArray returned from ObtainStyledAttributes() doesn't seem to have the corresponding custom values for the custom properties I've created, although I can map their IDs to the values in Resource.designer. Attr.xml: ``` ``` Main.xaml: ``` ``` View Class: ``` public HeaderView (Context context, IAttributeSet attrs) : base (context, attrs) { i…

Accepted Answer

I think the issue lies with how you specified your `xmlns:custom` namespace. You need to add your applications namespace at the end of the string your already have like so:

```
xmlns:custom="http://schemas.android.com/apk/res/my.awesome.namespace"
```

You also need to have a `AndroidManifest.xml` defined for your Android project, where you have defined the same namespace.

Also the lines:

```
int[] styleAttrs = Resource.Styleable.HeaderView;
TypedArray a = context.ObtainStyledAttributes(attrs, styleAttrs);
```

Look a bit strange to me and I would just write:

```
var a = context.ObtainStyledAttributes(attrs, Resource.Styleable.HeaderView);
```

Especially if you are not using `styleAttrs` later on.

EDIT: since Android SDK rev 17 it is possible to use:

```
xmlns:custom="http://schemas.android.com/apk/res-auto"
```

instead of having to write the entire namespace.

monodroid/xamarin custom attributes are empty using ObtainStyledAttributes

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