How to close in-panel custom widget from within onOpen()?

MichaelLev

In in-panel custom widget onOpen() function, if some critical config aram is empty, I output alert,

then I want to close the widget (as if someone clicked the "x" button, or as I have not clicked to open it at all).

I wrote:

            PanelManager.getInstance().closePanel(this.id + '_panel');

but it failed, maybe because I'm "inside" onOpen() ?

My questions:

1. How to nicely close in-panel custom widget programatically from within onOpen()?

2. My first lines of onPen() are:

               if (!this.isOpening) {
                     this.isOpening = true;

    Do I have to reset this.isOpening to false before I close the widget?

3. The code in WidgetManager.js id: