iview Modal 确定按钮loading

let _this = this
setTimeout(() => {
    _this.btnLoading = false;
    _this.$nextTick(() => {_this.btnLoading = true;});
}, 100)

this.$Modal.success({
    title: ‘‘,
    content: `<strong style="font-size:16px">确认成功</strong>`,
    onOk: () => {
        this.btnLoading = false;
        this.modal = false;
        // do something
    }
});