How to select items using Multi Combo Box
The best way to select an item in the combo box is to use the setMultiple activity. Below is a step by step process:
Make sure you have declared the variable using the element class Multi Combo Box as the element type.
If you want to find different SAPUI5 features you can find them here.
To use the activity make sure that you are adding the values, you want to select as a string as shown below:
SAPUI5.pUI5.multiCombobox.setMultiple("["Goldberry", "Comfort Easy", "Smart Design"]");