Question

I have a layout in XML as follows:

<LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:onClick="myButton.performClick" />

myButton is a member of this activity, is it possible use a class member method here?

Answer 1

No, as the docs say (emphasis mine):

you must declare a public void sayHello(View v) method of your context
(typically, your Activity)

If you wanted to execute a method on a field, you could wrap it I suppose.

<LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:onClick="performClick" />

Then:

public void performClick(View view) {
    myButton.performClick(view);
}

but that almost defeats the purpose of the XML onClick attribute (making things more concise). Is there a good reason for performClick to be on your button instead of your activity anyway?

Lastly, doing this on the LinearLayout is fine. The attribute is supported for all Views.