异步调用后读取 UISwitch 的状态
我有一个带有 UISwitch 的登录屏幕，让用户选择“记住我”，这样我就可以根据需要将他/她的凭据存储在钥匙链上。
仅当用户选择“记住我”并且服务器接受用户名/密码时才会发生这种情况。但是，当服务器回复时，我很难参考 UISwitch 的状态。令我惊讶的是，myUISwitch.on 的值为（null）。
NSLog (@"(Successful login. Value of UISwitch rememberMe: %@)", rememberMe.on);
我必须将此信息存储在临时布尔值中吗？
I have a loging screen with a UISwitch for letting the user choose "remember me" so I can store his/her credentials on the key chain if desired.
This will only happen if the user has chosen "remember me" AND the server accepts the username/password. However, when the server replies, I have a hard time referring to the state of the UISwitch. The value of myUISwitch.on is, to my surprise (null).
NSLog (@"(Successful login. Value of UISwitch rememberMe: %@)", rememberMe.on);
Must I store this information in a temporary boolean?
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如果为 null，则不是
on属性，而是rememberMe变量，该变量未设置。在 Interface Builder 或代码中正确连接它。另外，请确保始终从主线程访问 UIKit，即使用 PerformSelectorOnMainThread:
在此处输入代码。If it is null, it is not the
onproperty but therememberMevariable, which is not set. Wire it up correctly in Interface Builder or in code.Also, make sure to access UIKit always from the main thread, i.e. use performSelectorOnMainThread:
enter code here.当你引用switch的时候视图还没有释放吗？
UISwitch是否已被运行时释放？您什么时候尝试读取其状态？当您读取其状态时，控件是否仍在屏幕上？Is the view still not released by the time you refer to the switch? Is the
UISwitchalready released by the runtime? When did you attempt to read its state? Is the control still on the screen by the time you read its state?