Pallate Textbox

I have two textboxes in the panel. while Tabbing or entering into the Panel Textboxes Tab is applied onto the main page.As the cursor is in the main page also.

Below is the code.

var w = new Window ('palette', 'Add Note', undefined, {resizeable: true});

        var listContainer = w.add ("group");

        listContainer.orientation = 'column';

        ////////////////// Textbox

        var note = listContainer.add ('edittext', [0,0,120,100], "", {multiline:true});

        note.graphics.font = "Krishna:18";

        note.active = true;

        var pg = listContainer.add ('edittext', [0,0,120,70], "", {multiline:true});

        pg.graphics.font = "Calibri:12";

What can be the work around here..? Can we block the background page while typing in the panel..?