使用模型的 requestCompleted 事件处理程序来执行任何应该在模型数据更新后立即发生的操作.

Use the model's requestCompleted event handler to perform any actions that should happen right after your model data is updated.

绑定本身应该是静态的(即它不会改变)，所以你只对数据何时改变感兴趣

The binding itself should be rather static (i.e. it will not change) so you'r only interested in when the data is changed

编辑这里是一个示例实现:

var that = this;
oModelTriptab.attachRequestCompleted(function(oEvent){
    var oSelect = that.byId("CountrySelect");
    oSelect.setSelectedKey("whatever");
});

参见 https://openui5.hana.ondemand.com/docs/api/symbols/sap.ui.model.Model.html#attachRequestCompleted了解更多信息