sapui5 如何为同步 Ajax GET 请求提供忙碌指示器

Question

Im facing an issue in getting Busy Indicator while firing a synchronous request . But for asynchronous request iam able to see Busy Indicator . But my business requirement will not accpet async request here.

I checked in many blogs to find a solution , But unfortunately im not able to get solution.

Can someone please help me to provide Busy Indicator for synchronous request .

Below is my code..

       sap.ui.core.BusyIndicator.show(0); // Not working
       new sap.m.BusyDialog().open(); // Not working
        var settings = {
            "async": false, // If i change to true i can see busy indicator
            "crossDomain": true,
            "url": "URL", // URL of my App
            "method": "GET",
            "headers": {
                "cache-control": "no-cache"
            }
        };
        var that = this;
        $.ajax(settings).done(function (response) {
            
            sap.ui.core.BusyIndicator.hide(0);
            
        });

Answer 1

Title indicates using a UI5 model, given code is using query... question is a bit unclear.

Code is for a read using bindings(here V4, I think v2 has the same events), and setting the view busy during the request (that's an async request)

this.getView().bindElement({
            path: "/" + sObjectPath,
            events: {
                dataRequested: function() {
                    that.getView().setBusy(true);
                },
                dataReceived: function() {
                    that.getView().setBusy(false);
                }
            }
});

The V2 model supports also direct request (that's an async request) :

const that = this;
that.getView().setBusy(true);
oModel.read("/path", {
                success: function (oData) {
                       that.getView().setBusy(false);
                }
});

The same works with jQuery Ajax API (that's an async request) .

 const that = this;
 that.getView().setBusy(true);
 $.ajax(settings).done(function (response) {
        that.getView().setBusy(false);   
 });

Sync http-requests are deprecated . Sync would mean the UI is freezing while the request is running. Obviously, this is nowadays not desired. Some browsers dropped already support. As it was already pointed out by others. Keep in mind there is just one thread for your JS. See also