Figured it out myself.
editor.on('dblclick', function() {
alert('Current line is ' + editor.getCursorPosition().row);
});I am still curious about my other question, if there is an api to detect the line at coordinates (x, y)... There are some functions (EditSession.documentToScreenPosition and co ) but they don't do exactly this...
I am going to use the editor.getCursorPosition().row for now...