如何传递prepareForSegue:对象-HowtopassprepareForSegue:anobject

658  

Simply grab a reference to the target view controller in prepareForSegue: method and pass any objects you need to there. Here's an example...

只需在prepareForSegue:方法中获取对目标视图控制器的引用，并将需要的任何对象传递到那里。这里有一个例子……

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Make sure your segue name in storyboard is the same as this line
    if ([[segue identifier] isEqualToString:@"YOUR_SEGUE_NAME_HERE"])
    {
        // Get reference to the destination view controller
        YourViewController *vc = [segue destinationViewController];

        // Pass any objects to the view controller here, like...
        [vc setMyObjectHere:object];
    }
}

REVISION: You can also use performSegueWithIdentifier:sender: method to activate the transition to a new view based on a selection or button press.

修订:您还可以使用performSegueWithIdentifier:sender:方法根据选择或按下按钮激活到新视图的转换。

For instance, consider I had two view controllers. The first contains three buttons and the second needs to know which of those buttons has been pressed before the transition. You could wire the buttons up to an IBAction in your code which uses performSegueWithIdentifier: method, like this...

例如，假设我有两个视图控制器。第一个包含三个按钮，第二个需要知道在转换之前按了哪些按钮。您可以将这些按钮连接到代码中的IBAction，它使用performSegueWithIdentifier: method，如下所示…

// When any of my buttons are pressed, push the next view
- (IBAction)buttonPressed:(id)sender
{
    [self performSegueWithIdentifier:@"MySegue" sender:sender];
}

// This will get called too before the view appears
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([[segue identifier] isEqualToString:@"MySegue"]) {

        // Get destination view
        SecondView *vc = [segue destinationViewController];

        // Get button tag number (or do whatever you need to do here, based on your object
        NSInteger tagIndex = [(UIButton *)sender tag];

        // Pass the information to your destination view
        [vc setSelectedButton:tagIndex];
    }
}

EDIT: The demo application I originally attached is now six years old, so I've removed it to avoid any confusion.

编辑:我最初附加的演示应用程序现在已经有6年的历史了，所以我删除了它以避免任何混淆。

81  

The accepted answer is not the best way of doing this, because it creates an unnecessary compile-time dependency between two view controllers. Here's how you can do it without caring about the type of the destination view controller:

公认的答案不是最好的方法，因为它在两个视图控制器之间创建了不必要的编译时依赖。以下是如何在不考虑目标视图控制器类型的情况下完成的:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.destinationViewController respondsToSelector:@selector(setMyData:)]) {
        [segue.destinationViewController performSelector:@selector(setMyData:) 
                                              withObject:myData];
    } 
}

So as long as your destination view controller declares a public property, e.g.:

因此，只要您的目标视图控制器声明公共属性，例如:

@property (nonatomic, strong) MyData *myData;

you can set this property in the previous view controller as I described above.

如前所述，可以在前面的视图控制器中设置此属性。

19  

In Swift I would do something like that:

在《Swift》中，我会这样做:

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if let yourVC = segue.destinationViewController as? YourViewController {
        yourVC.yourData = self.someData
    }
}

16  

I have a sender class, like this

我有一个sender类，像这样

@class MyEntry;

@interface MySenderEntry : NSObject
@property (strong, nonatomic) MyEntry *entry;
@end

@implementation MySenderEntry
@end

I use this sender class for passing objects to prepareForSeque:sender:

我使用这个sender类将对象传递给prepareForSeque:sender:

-(void)didSelectItemAtIndexPath:(NSIndexPath*)indexPath
{
    MySenderEntry *sender = [MySenderEntry new];
    sender.entry = [_entries objectAtIndex:indexPath.row];
    [self performSegueWithIdentifier:SEGUE_IDENTIFIER_SHOW_ENTRY sender:sender];
}

-(void)prepareForSegue:(UIStoryboardSegue*)segue sender:(id)sender
{
    if ([[segue identifier] isEqualToString:SEGUE_IDENTIFIER_SHOW_ENTRY]) {
        NSAssert([sender isKindOfClass:[MySenderEntry class]], @"MySenderEntry");
        MySenderEntry *senderEntry = (MySenderEntry*)sender;
        MyEntry *entry = senderEntry.entry;
        NSParameterAssert(entry);

        [segue destinationViewController].delegate = self;
        [segue destinationViewController].entry = entry;
        return;
    }

    if ([[segue identifier] isEqualToString:SEGUE_IDENTIFIER_HISTORY]) {
        // ...
        return;
    }

    if ([[segue identifier] isEqualToString:SEGUE_IDENTIFIER_FAVORITE]) {
        // ...
        return;
    }
}

11  

I came across this question when I was trying to learn how to pass data from one View Controller to another. I need something visual to help me learn though, so this answer is a supplement to the others already here. It is a little more general than the original question but it can be adapted to work.

我在学习如何将数据从一个视图控制器传递到另一个视图控制器时遇到了这个问题。我需要一些视觉上的东西来帮助我学习，所以这个答案是对其他已经存在的答案的补充。它比最初的问题更一般一些，但是它可以用于工作。

This basic example works like this:

这个基本示例如下所示:

The idea is to pass a string from the text field in the First View Controller to the label in the Second View Controller.

其思想是将字符串从第一个视图控制器中的文本字段传递给第二个视图控制器中的标签。

import UIKit

class FirstViewController: UIViewController {

    @IBOutlet weak var textField: UITextField!

    // This function is called before the segue
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {

        // get a reference to the second view controller
        let secOndViewController= segue.destinationViewController as! SecondViewController

        // set a variable in the second view controller with the String to pass
        secondViewController.receivedString = textField.text!
    }

}

import UIKit

class SecondViewController: UIViewController {

    @IBOutlet weak var label: UILabel!

    // This variable will hold the data being passed from the First View Controller
    var receivedString = ""

    override func viewDidLoad() {
        super.viewDidLoad()

        // Used the text from the First View Controller to set the label
        label.text = receivedString
    }

}

• Make the segue by control clicking on the button and draging it over to the Second View Controller.
• 通过控件单击按钮并将其拖放到第二个视图控制器来进行segue。
• Hook up the outlets for the UITextField and the UILabel.
• 连接UITextField和UILabel的outlet。
• Set the first and second View Controllers to the appropriate Swift files in IB.
• 将第一和第二视图控制器设置为IB中相应的Swift文件。

How to send data through segue (swift) (YouTube tutorial)

如何通过segue (swift)发送数据(YouTube教程)

View Controllers: Passing data forward and passing data back (fuller answer)

视图控制器:向前传递数据并返回数据(更完整的答案)

4  

I've implemented a library with a category on UIViewController that simplifies this operation. Basically, you set the parameters you want to pass over in a NSDictionary associated to the UI item that is performing the segue. It works with manual segues too.

我在UIViewController中实现了一个类的库，它简化了这个操作。基本上，您设置了要在与执行segue的UI项相关的NSDictionary中传递的参数。它也适用于手动segue。

For example, you can do

例如，你可以这样做

[self performSegueWithIdentifier:@"yourIdentifier" parameters:@{@"customParam1":customValue1, @"customValue2":customValue2}];

for a manual segue or create a button with a segue and use

用于手动segue或使用segue创建按钮

[button setSegueParameters:@{@"customParam1":customValue1, @"customValue2":customValue2}];

If destination view controller is not key-value coding compliant for a key, nothing happens. It works with key-values too (useful for unwind segues). Check it out here https://github.com/stefanomondino/SMQuickSegue

如果目标视图控制器不符合键值编码，则不会发生任何事情。它也适用于键值(对展开segue很有用)。在这里查看https://github.com/stefanomondino/SMQuickSegue

4  

For Swift use this,

斯威夫特用这个,

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    var segueID = segue.identifier

    if(segueID! == "yourSegueName"){

        var yourVC:YourViewCOntroller= segue.destinationViewController as YourViewController

        yourVC.objectOnYourVC= setObjectValueHere!

    }
}

2  

My solution is similar.

我的解决方案是相似的。

// In destination class: 
var AddressString:String = String()

// In segue:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
   if (segue.identifier == "seguetobiddetailpagefromleadbidder")
    {
        let secOndViewController= segue.destinationViewController as! BidDetailPage
        secondViewController.AddressString = pr.address as String
    }
}

0  

I used this solution so that I could keep the invocation of the segue and the data communication within the same function:

我使用了这个解决方案，这样我就可以在同一个函数中调用segue和数据通信:

private var segueCompletion : ((UIStoryboardSegue, Any?) -> Void)?

func performSegue(withIdentifier identifier: String, sender: Any?, completion: @escaping (UIStoryboardSegue, Any?) -> Void) {
    self.segueCompletion = completion;
    self.performSegue(withIdentifier: identifier, sender: sender);
    self.segueCompletion = nil
}

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    self.segueCompletion?(segue, sender)
}

A use case would be something like:

一个用例应该是这样的:

func showData(id : Int){
    someService.loadSomeData(id: id) {
        data in
        self.performSegue(withIdentifier: "showData", sender: self) {
            storyboard, sender in
            let dataView = storyboard.destination as! DataView
            dataView.data = data
        }
    }
}

This seems to work for me, however, I'm not 100% sure that the perform and prepare functions are always executed on the same thread.

但是，这似乎对我来说是有效的，但是，我不能百分之百地确定执行和准备函数总是在同一个线程上执行。

0  

Just use this function.

使用这个函数。

 override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    let index = CategorytableView.indexPathForSelectedRow
    let indexNumber = index?.row
    let VC = segue.destination as! DestinationViewController
   VC.value = self.data

}