xcode 在转发类对象上找不到属性？
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Property cannot be found on forward class object?
提问by user339946
I have a UIView and I'm trying to set its layer properties.
我有一个 UIView，我正在尝试设置它的图层属性。
self.colorSwatch = [[UIView alloc] initWithFrame:CGRectMake(400, 150, 100, 100)];
self.colorSwatch.layer.cornerRadius = 8;
However, when I try to access the .layer.cornerRadiusproperty, I get a warning that says "Property 'cornerRadius' cannot be found in forward class object 'CALayer *'.
但是，当我尝试访问该.layer.cornerRadius属性时，我收到一条警告，指出“在前向类对象‘CALayer *’中找不到属性‘cornerRadius’。
What does this mean? Thanks
这是什么意思？谢谢
回答by Jim
It doesn't know what type of object the layerproperty is. Add #import <QuartzCore/QuartzCore.h>to the top of your file.
它不知道该layer属性是什么类型的对象。添加#import <QuartzCore/QuartzCore.h>到文件的顶部。
回答by Mukesh
You need to import the file #import < QuartzCore/QuartzCore.h> in ViewController.m class if and only if xcode version is less than 5.
当且仅当 xcode 版本小于 5 时，您需要在 ViewController.m 类中导入文件 #import <QuartzCore/QuartzCore.h>。
See if you are using xcode version 5 or latest than that then not required to import .It is automatically included.
查看您使用的是 xcode 版本 5 还是最新版本，然后不需要导入。它会自动包含在内。
