ios - 如何使用状态恢复来恢复视图控制器的子视图

Question

我正在使用状态恢复为我的应用程序恢复以前的视图和数据。当在第一个视图控制器中单击一个按钮时，我将推送第二个视图控件。在这种情况下，我可以恢复第二个视图控制器数据。但是如果我添加第二个当在第一个视图控制器中单击按钮时，将视图控制器视图作为第一个视图控制器的子视图，在第二个视图控制器中未调用 encodeRestorableStateWithCoder：和 decodeRestorableStateWithCoder：。无法恢复第二个视图控制器数据。我需要做任何其他配置来恢复子视图数据 ？

//Firstviewcontroller

-(IBAction)moveToNextViewController:(id)sender {

 SecondVeiwController *sec_VC=[[SecondVeiwController alloc]initWithNibName:@"SecondVeiwController" bundle:[NSBundle mainBundle ]];
    sec_VC.restorationIdentifier=@"SecondVeiwController";

    [self.view addSubview:tab_cnt_1.view];

}





//Secondviewcontroller

-(id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{

    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
        self.restorationIdentifier=@"Secondviewcontroller";
        self.restorationClass=[self class];
    }
    return self;

}

+(UIViewController *)viewControllerWithRestorationIdentifierPath:(NSArray *)identifierComponents coder:(NSCoder *)coder
{

    UIViewController * myViewController =
    [[Secondviewcontroller alloc]
     initWithNibName:@"Secondviewcontroller"
     bundle:[NSBundle mainBundle]];

    return myViewController;

}

Answer 1

似乎iOS没有跟踪子视图，您必须对 SecondViewController 进行编码，然后将其解码并添加为子视图控制器，并将其视图作为子视图。

//FirstViewController

-(void)encodeRestorableStateWithCoder:(NSCoder *)coder {

    [super encodeRestorableStateWithCoder:coder];

    [coder encodeObject:self.childViewControllers[0] forKey:@"childVC"];
}

-(void)decodeRestorableStateWithCoder:(NSCoder *)coder {

    [super decodeRestorableStateWithCoder:coder];

    UIViewController *v = [coder decodeObjectForKey:@"childVC"];

    [self addChildViewController:v];

    [self.view addSubview:v.view];
}


//SecondViewController

-(void)encodeRestorableStateWithCoder:(NSCoder *)coder {

    [super encodeRestorableStateWithCoder:coder];

    [coder encodeObject:self.view.backgroundColor forKey:@"bgColor"];
}

-(void)decodeRestorableStateWithCoder:(NSCoder *)coder {

    [super decodeRestorableStateWithCoder:coder];

    UIColor *bgColor = [coder decodeObjectForKey:@"bgColor"];

    [self.view setBackgroundColor:bgColor];
}