Try this:
$(...).combobox('textbox').tooltip({...});
It work. Thank you.
but other question:
how to display the tooltip on the combobox's drop-down-button position:'right'?
OK,I find the way:
$(':text[field="domain"]').combobox(
{
valueField: 'id',
textField: 'text',
panelHeight: 'auto',
value: "hsgroup",
data: [{ "id": "AA", "text": "AA" }, { "id": "BB", "text": "BB"}]
}
).combobox('textbox')
.focus(function(e) {
$(this).next().tooltip({
content: 'Test combobox tooltip',
position: 'right'
}).tooltip('show');
})
.blur(function(e) {
$(this).next().tooltip('hide');
});