UIViewController中的view显示步骤
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进入UIViewController时的情况:
viewDidLoad
viewWillLayoutSubviews
viewDidLayoutSubviews
viewWillAppear
viewWillLayoutSubviews
viewDidLayoutSubviews
viewDidAppear
切换了Controller后的情况(比如你在TabbarController中切换了):
viewWillDisappear
viewDidDisappear
再次切换回来后的情况:
viewWillLayoutSubviews
viewDidLayoutSubviews
viewWillAppear
viewWillLayoutSubviews
viewDidLayoutSubviews
viewDidAppear
退入到后台后的情况:
无
从后台进入程序时的情况:
viewWillLayoutSubviews
viewDidLayoutSubviews
