将数据发送到全球 HUD、Cocoa 的概念帮助
我有一个多文档申请。
我想从每个文档中提取数据，并将数据的子集镜像到可以位于另一个屏幕上的全局“管理”HUD 窗口中。
我是否需要在每个文档实例中使用 HudController 的全局对象，或者是否有一种方法可以将各个文档中的所有信息委托给 HudController 作为其自己的实例？
感谢您的帮助！
I have a multidocument application.
I want to pull data from each of those documents and mirror a subset of the data into a global 'management' HUD window that can sit on another screen.
Do I need a global object of my HudController in each document instance or is there a way I can delegate all the info from the various documents to the HudController as its own instance?
thanks for any help!
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（1）
这是单例适用的一种情况。还有一些类似面板的其他示例；字体面板和颜色面板的工作方式相似。所以，让你的 HudController 成为一个单例（我有关于如何最好的建议来做到这一点）。
然后，让 HudController 监视文档的更改。细节会有所不同，但您可能希望为文档类提供公共属性，通过这些属性来访问模型，然后让 HudController 监视文档窗口的打开和关闭；当发生其中一种情况时，让 HudController 开始或结束观察 每个窗口的匹配文档的那些属性。
只要您以 KVO 兼容的方式更改属性值，更改就会自动向 HudController 发出通知，然后您将通过更新 HUD 窗口中显示的内容来响应更改。
This is one case where a singleton is appropriate. There are a few other examples of similar panels; the Font Panel and Color Panel both work in a similar way. So, make your HudController a singleton (I have suggestions on how best to do that).
Then, have the HudController monitor the documents for changes. Details will vary, but you'll probably want to give the document class(es) public properties through which to access the model, then have the HudController watch for document windows being opened and closed; when one of those happens, have the HudController begin or end observing those properties of each window's matching document.
As long as you change the values of the properties in a KVO-compatible way, the change will cause a notification to the HudController automatically, whereupon you'll respond to the change by updating what you display in the HUD window.