How to use the progress/Progress.start function in progress

it("Progress", () => {
        chai.assert.equal(Progress.instance().isStarted(), false);
        Progress.start();
        chai.assert.equal(Progress.instance().isStarted(), true);
        chai.assert.equal(Progress.instance().settings.showSpinner, false);

        Progress.configure({ showSpinner: true });
        chai.assert.equal(Progress.instance().settings.showSpinner, true);

        Progress.done();
        chai.assert.equal(Progress.instance().isStarted(), false);
    });
});

__onComponenListClick = (e: Object) => {
        this.setState({
            componentSelection: `Docs/${e.target.text}`
        });
        Progress.start();
    };
}

__onSelect(key:string) {
        Progress.start();
        if (key === "React-Bootstrap") {
            window.open("https://react-bootstrap.github.io/components.html");
            return;
        }

        switch (key) {
            case "en_US":
            case "tr_TR":
                this.setState({
                    language: `assets/${key}.json`
                });
                return;
        }
        window.location.hash = `#${key}`;

        let element = document.getElementById("activePage");

__onSelect(key: string) {
        Progress.start();
        if (key === "React-Bootstrap") {
            window.open("https://react-bootstrap.github.io/components.html");
            return;
        }

        if (key === "github") {
            window.open("https://github.com/robeio/robe-react-ui");
            return;
        }

        if (key === "en_US" || key === "tr_TR" || key === "ru_RU") {
            if (this.props.changeLanguage) {
                this.props.changeLanguage(`${key}.json`);
            }
            return;
        }

__onComponenListClick = (e: Object) => {
        this.setState({
            componentSelection: `Components/${this.state.selectedGroup}/${e.target.text}`
        });
        Progress.start();
    };