在ui5 javascript中使用前缀`o`

Question

I have seen people are using prefix o a lot when developing ui5 application.

var oRowsModel = new sap.ui.model.json.JSONModel();
    oValueHelpDialog.getTable().setModel(oRowsModel);
   if (oValueHelpDialog.getTable().bindRows){
    oValueHelpDialog.getTable().bindRows("/"); 
}

this.getView().setModel(oModel);

var oSelectedItem = oEvent.getParameter("selectedItem"),
            oTimeline = this.getView().byId("ActivityTimeline"),
            oTimelineBinding = oTimeline.getBinding("content");

Does it help somehow ? Is it a best practice ? What is the advantage?

I think that a lot of things are objects and specifying o does not help much. Why then to use it?

Answer 1

The prefixing of variables is just a naming convention carried over from the native SAP programming language called ABAP. In ABAP it is a long standing convention to prefix variables so that one can tell the type of the variable and if the variable is local or global, for instance lv_myvar for a local variable, and gt_mytab for a table type that is global. There is really no particular reason to continue with this practice in Javascript and UI5 - if you don´t like, don´t do it.

Answer 2

o for Object maybe? :)

Plus it makes sense, to append an 'o' to your variable name,as you shall be fiddling around with objects all the time.

Plus, it helps much to use oList instead of List, as it is a control.

Answer 3

o means object. You can see here