如何修复“在 Xcode 4.2 之前无法使用自由格式大小模拟指标”警告？
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How can I fix "Freeform Size simulated metrics are not available prior to Xcode 4.2" warnings?
提问by Dirty Henry
Since a couple of weeks, I've been using XCode 4.2 with projects created with previous XCode 3.x versions.
几个星期以来，我一直在使用 XCode 4.2 和以前的 XCode 3.x 版本创建的项目。
When creating some custom iPad views, I often use the "freeform" attribute of Interface Builder to be able to have views with an arbitrary size.
在创建一些自定义 iPad 视图时，我经常使用 Interface Builder 的“freeform”属性来拥有任意大小的视图。
But then, I get build the following build warnings: "warning: Attribute Unavailable: Freeform Size simulated metrics are not available prior to Xcode 4.2."
但是，我得到了以下构建警告：“警告：属性不可用：在 Xcode 4.2 之前，自由格式大小模拟指标不可用。”
My question is: how can I fix these warnings?
我的问题是：如何修复这些警告？
ps: First, I assumed it meant my project wouldn't be backward-compatible with earlier versions of XCode (which doesn't bother me at all) and tried to tell Xcode so, by setting the Project Format to XCode 4.2-compatible only. Unfortunately, the dropdown menu for the project format only suggests "XCode 3.2-compatible" and "XCode 3.1-compatible".
ps：首先，我认为这意味着我的项目不会与早期版本的 XCode 向后兼容（这根本不打扰我）并试图通过将项目格式设置为 XCode 4.2-compatible 来告诉 Xcode . 不幸的是，项目格式的下拉菜单只建议“XCode 3.2-compatible”和“XCode 3.1-compatible”。
回答by kyleobrien
Open the .xib file in question and show the Utilities pane. Click on the File Inspector tab and under Interface Builder Document you'll see a Development field. Change it to Xcode 4.2.
打开有问题的 .xib 文件并显示“实用工具”窗格。单击 File Inspector 选项卡，在 Interface Builder Document 下，您将看到 Development 字段。将其更改为 Xcode 4.2。
