Remove the text from combobox when click

I using dhtmlXCombo for search channels, intially when page load i do setText by z.setComboText(‘Search channel’);

now i need to clear Text ‘Search channel’ set previosly on mouse click, is this possible

Is this possible and how do i go about doing this ?

Thanking in advance for all good work DHTMLX is doing


The next must provide necessary behavior

return true;