ios - 从其他 UIViewController 更改 UIViewController 的背景颜色

Question

我已经在另一个UIviewController之上分配了一个。我想从这个新 Controller 更改另一个 Controller 的颜色，但我不知道如何操作。我试过这个:

-(IBAction)sliderValueChanged:(UISlider *)sender
{
NSLog(@"slider value = %f", sender.value);

ViewController1.view.backgroundColor = [UIColor colorWithRed:(160/sender.value) green:(97/sender.value) blue:(5/sender.value) alpha:0.6];
}

并导入了ViewController1，但出现错误。如果我放置 self.view ，它会正常工作，但不能在 ViewController1 上。我该怎么做？

Answer 1

看起来您实际上并没有存储对要更改其背景颜色的 UIViewController 的引用。尝试为您正在显示的 View Controller 创建一个属性，然后执行如下操作:

@implementation MyPoppingController

-(void)showViewController
{
    UIStoryboard* sb = [UIStoryboard storyboardWithName:@"StoryboardInfo" bundle:nil];        
    self.myPopController = [sb instantiateInitialViewController]; 
    self.myPopController.myPresentingViewController = self;
    [self presentPopupViewController:self.myPopController animationType:MJPopupViewAnimationFade]; 
}
@end


@interface MyPoppedController

@property(strong, nonatomic) MyPopppingController *myPresentingViewController;

@end

@implementation MyPoppedController

-(IBAction)sliderValueChanged:(UISlider *)sender
{
    self.myPresentingViewController.view.backgroundColor = [UIColor colorWithRed:(160/sender.value) green:(97/sender.value) blue:(5/sender.value) alpha:0.6];
}

@end