[Flutter Error]The following RangeError was thrown building KeyedSubtree-[<0>]: RangeError (index): Invalid value: Valid value range is empty: 0

错误：

The following RangeError was thrown building KeyedSubtree-[<0>]:
RangeError (index): Invalid value: Valid value range is empty: 0

原因：

运行时还没获取到数据，就执行了 类似这样的数据输出，
child: Text('${this._newsDataList[index].title}'

解决方法：对数据是否获取到进行判断。

添加 this._newsDataList.length > 0

return this._newsDataList.length > 0
    ? ListView.builder(
    ...
)
    : Container(
        margin: EdgeInsets.all(ScreenAdapter.setHeight(20)),
        height: ScreenAdapter.setHeight(800),
    );