I'm very sorry I must use Google Translate. Hopefully you can make some sense of the translation!
非常抱歉，我必须使用Google翻译。 希望您能对翻译有所了解！我会先写英文，然后再写中文。
At runtime, a skeleton has two skins:
1) Skeleton skin is usually the skin you want to some other skin. This is equivalent to selecting a skin in the Spine editor.
2) SkeletonData defaultSkin contains all the attachments that aren't in a skin in the Spine editor.
在运行时，骨骼具有两个外观：
1）Skeleton skin通常是您想要其他皮肤的皮肤。 这等效于在Spine编辑器中选择外观。
2）SkeletonData defaultSkin包含了所有不在Spine编辑器皮肤中的附件。
When an attachment is needed, for example an animation's AttachmentTimeline needs to set an attachment, it is usually done by calling Skeleton setAttachment. That function first looks in Skeleton skin and uses the attachment found. If no attachment is found, it then looks in SkeletonData defaultSkin.
当需要附件时，例如动画的 AttachmentTimeline 需要设置附件，通常可以通过调用Skeleton setAttachment来完成。该函数首先在Skeletonskin中查找并使用找到的附件。 如果没有找到附件，它将在SkeletonData defaultSkin中查找。
You can change the SkeletonData defaultSkin, but you don't normally want to since it contains items not in a skin in the Spine editor. Instead, you usually only change Skeleton skin.
您可以更改SkeletonData defaultSkin，但通常不希望这样做，因为它包含Spine编辑器中皮肤中未包含的项目。 取而代之的是，您通常只更改Skeleton skin。
At runtime you can create a new skin (or make a copy of an existing skin) and then set the attachments on it or add other skins to it. This allows you to assemble a skin with all the attachments you want, then you would use that to set Skeleton skin. Please see this page:
Runtime Skins - Spine Runtimes Guide
That is the Chinese page, but please note that the English page has a little bit more information about combining skins:
Runtime Skins - Spine Runtimes Guide: Grouping attachments
Sorry the Chinese page doesn't have that section yet! It's very difficult to keep all the translations updated.
在运行时，您可以创建一个新的外观（或复制现有外观），然后在其上设置附件或向其添加其他外观。这使您可以将皮肤与所需的所有附件组合在一起，然后使用它来设置Skeleton skin。请查看此页面：
Runtime Skins - Spine Runtimes Guide
那是中文页面，但是请注意，英文页面提供了更多有关组合外观的信息：
Runtime Skins - Spine Runtimes Guide: Grouping attachments
抱歉，中文页面还没有该部分！保持所有翻译都是最新的非常困难。
Also take a look at the API reference for Skin, which shows the methods you can use to configure the skin:
另外，请参阅皮肤的API参考，其中显示了可用于配置皮肤的方法：
Skin
