In this case the variable oFld is undefined when you press the button.
Use something like this:
oFld.setAction(MouseUp", "app.alert(\"" + oFld.name + "\");");
or
oFld.setAction(MouseUp", "app.alert(event.target.name);");
In this case the variable oFld is undefined when you press the button.
Use something like this:
oFld.setAction(MouseUp", "app.alert(\"" + oFld.name + "\");");
or
oFld.setAction(MouseUp", "app.alert(event.target.name);");