The label field in this extension is optional.

这个扩展中的标签域是可选择的。

youdao

The navigator content extension defines a content provider and label provider that can be used to provide children and parent objects for element of an EMF model.

导航器内容扩展定义了内容提供程序和标签提供程序，可以使用这些程序为emf模型的元素提供子对象和父对象。

youdao

First, we need to create a new content extension where we can specify the content and label providers to be used by the common navigator, later we will implement these classes.

首先，我们需要创建新的内容扩展，在其中指定通用导航器使用的内容和标签提供程序，稍后我们将实现这些类。

youdao

Announcing the failure of the latest trial Tuesday, the two companies said they would halt development of Dimebon for all indications and cease an ongoing open-label extension study in Alzheimer's disease.

WSJ: Medivation, Pfizer Alzheimer's Drug Fails to Meet Study Goals