unable to selected items high lighted while edit the form

[dipranjans]

Hi All,
Please help me. i am using this multi-select to insert id into db using angular as front-end. but while edit the form the selected options i need to high-light inside the multiselect drop down so that i can edit and update further...?

How i can do that?

Below is the example:
JS:

inside controller:
this.jsontree={};
this.products=[list of array of products];

html

<multiselect ng-model="$ctrl.jsontree.test" options="$ctrl.products" show-search="true" id-prop="id" display-prop="name" search-limit="10"> </multiselect>

i selec 10 products but while edit its highlighting the selected products... how i can do that?