1.導航欄的顯示與隱藏：

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    self.navigationController.navigationBarHidden = YES;
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear: animated];
    self.navigationController.navigationBarHidden = NO;
}

2.狀態(tài)欄的顯示與隱藏：

實現(xiàn)之前需要在Info.plist配置：

• Status bar is initially hidden 設為 YES
• View controller-based status bar appearance 設為 NO
  這樣才會起作用。

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    [UIApplication sharedApplication].statusBarHidden = YES;
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear: animated];
    [UIApplication sharedApplication].statusBarHidden = NO;
}