Using MvxCommand With CommandParameter binding

Eugene Smykov picture Eugene Smykov · Jun 21, 2013 · Viewed 10.5k times · Source

I'm trying using fire MvxCommand with CommandParameter, but faced with following problem: MyView.axml contains:

<LinearLayout
    android:orientation="horizontal"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button1"
        local:MvxBind="Click MyCommand, CommandParameter=foo" />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button2"
        local:MvxBind="Click MyCommand, CommandParameter=bar" />
</LinearLayout>

MyViewModel.cs:

public class MyViewModel : MvxViewModel
{
    public ICommand MyCommand { get; private set; }

    public MyViewModel()
    {                                    // param is null
      MyCommand = new MvxCommand<string>(param =>
      {
          if (param == "foo")               
          {
            // do something
          }
          else if (param == "bar")
          {
            // do something else
          }
      });
    }
}

But when I check param variable is null.

What I'm doing wrong?

Answer

Stuart picture Stuart · Jun 21, 2013

Your code is working for me on the Head of my source tree.

But this functionality is only two weeks old.

My guess is that this feature either didn't make it into the release that you are working with or there was a bug with it.

Can you check your debug trace for this binding? Is there any information there?

  • If the trace suggests that CommandParameter is an unknown symbol then my guess is that you will need to either build the latest source yourself - or to wait for a new release.
  • If the trace suggests something else then you may be able to patch the problem during setup.

One thing I know we did fix was a value converter issue where the Cirrious.MvvmCross.Binding.dll based ValueConverter's weren't being just by overriding Setup.ValueConverterAssemblies to register the ValueConverter required for this CommandParameter