推送UINavigationController

Question

我在推送viewcontroller方面遇到了问题。这就是我做的：点击一个按钮，我使用这段代码添加一个模态视图我就可以了：

- (void)addAction:(id)sender
{
    uipickerForContract *addViewController = [[uipickerForContract alloc] initWithNibName:@"uipickerForContract" bundle:nil];
    addViewController.delegate = self;

    addViewController.modalPresentationStyle = UIModalPresentationFormSheet;
    addViewController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;

    [self presentModalViewController:addViewController animated:YES];

    addViewController.view.superview.frame = CGRectMake(50, 740, 695, 245);


}

这个添加的viewcontroller包含一个完成按钮，我想用它来导航到其他viewcontroller：所以我使用那个代码但它不起作用，它只是忽略了addeview：

 donebutton{

    nextview*s = [[nextview alloc]initWithNibName:@"nextview" bundle:nil];
    s.view.frame = CGRectMake(10, 20, 745, 755);
    //nextview contains the object that I want to pass :object
        s.object= self;
        UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:self];
    [self dismissModalViewControllerAnimated:YES];
         [self.navigationController pushViewController:s animated:YES];
        NSLog(@"self.nav%@",self.navigationController);
     }

Answer 1

视图控制器的self.navigationController（以模态方式呈现）将为nil

并且您无法注意到这一点，因为您正在分配导航控制器对象。

Answer 2

你需要在解雇和下一次这样的事情之间加点延迟

之前：

nextview*s = [[nextview alloc]initWithNibName:@"nextview" bundle:nil];
s.view.frame = CGRectMake(10, 20, 745, 755);
//nextview contains the object that I want to pass :object
    s.object= self;
    UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:self];
[self dismissModalViewControllerAnimated:YES];
     [self.navigationController pushViewController:s animated:YES];
    NSLog(@"self.nav%@",self.navigationController);

之后：

[self dismissModalViewControllerAnimated:YES];
[self performSelector:@selector(pushNextView) withObject:nil afterDelaye:0.40];

- (void) pushNextView {
    nextview*s = [[nextview alloc]initWithNibName:@"nextview" bundle:nil];
    s.view.frame = CGRectMake(10, 20, 745, 755);
    //nextview contains the object that I want to pass :object
        s.object= self;
        UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:self];

         [self.navigationController pushViewController:s animated:YES];
        NSLog(@"self.nav%@",self.navigationController);
}