HarmonyOS 在EntryAbility里getContext是undefined这里是拿不到的吗

在onWindowStageCreate可以使用this.context，如果使用getContext(this)获取不到context。示例参考：

let preferences: dataPreferences.Preferences | null = null;

class EntryAbility extends UIAbility {
  onWindowStageCreate(windowStage: window.WindowStage) {
    dataPreferences.getPreferences(this.context, 'myStore', (err: BusinessError, val: dataPreferences.Preferences) => {
      if (err) {
        console.error("Failed to get preferences. code =" + err.code + ", message =" + err.message);
        return;
      }
      preferences = val;
      console.info("Succeeded in getting preferences.");
    })
  }
}

参考链接：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-data-preferences-V5