There is no "currently selected parameter", except you press a mousebutton within a parameters window or while you typing into an input field.

This all is a UI Thing. Means: WxPython for Poser. The "Poser Engine" itself gets informed from the UI and is happy to share this information with a running Python script ("Parameter Callback").

In every WxPython UI lives a central "Event Processor". For Poser it is reachable via poser.WxApp(). This main Event Processor manages the whole UI.

All WxWindows from the UI are reachable via poser.WxAuiManager(). Each window is mainly managed via Events.

This also means: A script is able to mimic a keypress or mouseclick. Just put a prepared event object into the Event Queue and it will get processed (See WxPythons event handling online).

My opinion: Capturing Posers UI seams more complicated, time consuming and errorprone as writing a "PoserAddon".

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