ios - 如何快速将 UITextField 值传递给 .m 文件？

Question

我已经完成了桥接，我可以将值从 .m 文件发送到 swift 文件，反之亦然。 我的问题是我无法将 UITextField 值从 swift 发送到 .m。

我的代码是

快速文件

import UIKit

class ViewController: UIViewController {

@IBOutlet var txt: UITextField!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

     txt.text = "swift"

    //---- call property and method from  objective-C
    var instanceOfCustomObject: CustomObject = CustomObject()

    instanceOfCustomObject.someMethod()

    var propertyFromObjC: AnyObject! = instanceOfCustomObject.someProperty
    println("value from objective-C \(propertyFromObjC)")


}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

}

.m文件是

#import <Foundation/Foundation.h>

#import "CustomObject.h"

#import "Bridging-Swift.h"

@implementation CustomObject


- (void) someMethod {

    _someProperty=@"someProperty";

    NSLog(@"valueFromObjective-C method");
    ViewController *swiftObj = [ViewController new];
    NSLog(@"value from swift textfield %@", swiftObj.txt.text );
}

@end

结果是: valueFromObjective-C 方法 来自 swift 文本字段的值(null)---这是我的问题 来自 Objective-C someProperty 的值

Answer 1

你正在创建一个 ViewController 类的新对象

ViewController *swiftObj = [ViewController new];

这将是一个新对象，而不是您要访问的对象。这就是它给你 nil 的原因。

您可能必须通过 init 或其他方式将 ViewController 的实例传递给您的 CustomObject，以便在您的 somemethod() 中访问它。

@implementation CustomObject

- (id) initWithViewController:(ViewController*) vc {
    self.vc = vc
}

- (void) someMethod {

    _someProperty=@"someProperty";

    NSLog(@"valueFromObjective-C method");

    NSLog(@"value from swift textfield %@", self.vc.txt.text );
}
@end

swift 方面:

override func viewDidLoad() {
 super.viewDidLoad()

 txt.text = "swift"

 //---- call property and method from  objective-C
 var instanceOfCustomObject: CustomObject = CustomObject(self)

 instanceOfCustomObject.someMethod()

 var propertyFromObjC: AnyObject! = instanceOfCustomObject.someProperty
 println("value from objective-C \(propertyFromObjC)")
}