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jaxim's avatar
jaxim
Visitor
7 years ago

Button to Listen to Focus Event?

I've created a custom component that extends the button class. I would like to listen to a Focus event within the custom component so I can tell the UI nodes to display differently when the component is in focus. I've tried to listen to the focusPercent field within component's interface like below but the eventhandler is never called.


<field id="focusPercent" type="float" onChange="itemFocusChanged"/>


How do I get this custom component/button to listen to the focus event so I can have it react to getting into and out of focus?


p.s. This is how I am setting the button into focus: button.setFocus(true)
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3 Replies

  • joetesta's avatar
    joetesta
    Roku Guru
    7 years ago
    button and Group (which button is extended from) don't have a focusPercent field, afaik.
    You could do this; In your .brs script, add an observer to the button's focusedChild:

    ...
      m.button.observeField("focusedChild", "focusChanged")
    ...

    sub focusChanged()
      if m.button.hasFocus()
        ' the button has focus, decorate accordingly'
      else
        ' the button lost focus, undecorate accordingly'
      end if
    end sub

    Actually you probably need to use "m.top" instead of "m.button" assuming this script is in the actual button brs.
  • jaxim's avatar
    jaxim
    Visitor
    7 years ago
    That worked! This seems like a bug. It seems like an oversight not to officially support a buttons onFocus event instead of having to use a workaround like this.
    Thanks!

    m.top.observeField("focusedChild", "onFocusChanged")