在我的 Storyboard 中,我使用带有导航栏的 UINavigationController 来呈现视图控制器。这个视图控制器 ViewController2 通过点击我放置在导航栏中的 UIBarButtonItem 被推送到堆栈。我在 Interface Builder 中通过从栏按钮拖动到 ViewController2 场景并为 segue 选择“push”来建立这种连接。要返回第一个视图控制器,我有一个IBAction
调用该方法的popViewControllerAnimated
方法。我正在使用委托方法将数据发送回第一个视图控制器,但来自 ViewController2 的字符串没有被发送回 ViewController。
如何使用委托方法将 ViewController2 中输入的文本传递回第一个 ViewController?
视图控制器.h
#import <UIKit/UIKit.h>
@interface ViewController : UIViewController
@end
视图控制器.m
#import "ViewController.h"
#import "ViewController2.h"
@interface ViewController () <UITableViewDelegate,UITableViewDataSource,Vc2Delegate>
@property (strong,nonatomic) NSArray *tableArray;
@property (weak,nonatomic) IBOutlet UITableView *listTableView;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[self.listTableView setDelegate:self];
[self.listTableView setDataSource:self];
self.tableArray = @[@"item 1",@"item 2",@"item 3"];
ViewController2 *vc2 = [[ViewController2 alloc] init];
[vc2 setDelegate:self];
}
# pragma mark - TableView
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return self.tableArray.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"ItemCell" forIndexPath:indexPath];
cell.textLabel.text = [self.tableArray objectAtIndex:indexPath.row];
return cell;
}
#pragma mark - Delegate Method
- (void)returnFromVc2:(NSString *)userString {
NSLog(@"delegate text is %@",userString);
}
@end
ViewController2.h
#import <UIKit/UIKit.h>
@protocol Vc2Delegate <NSObject>
- (void)returnFromVc2:(NSString *)userString;
@end
@interface ViewController2 : UIViewController
@property (weak,nonatomic) id <Vc2Delegate> delegate;
@end
视图控制器2.m
#import "ViewController2.h"
@interface ViewController2 ()
@property (weak,nonatomic) IBOutlet UITextField *textField;
@end
@implementation ViewController2
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
}
- (IBAction)toPreviousVC:(id)sender {
NSLog(@"user text is: %@",self.textField.text);
[self.delegate returnFromVc2:self.textField.text];
[self.navigationController popViewControllerAnimated:YES];
}
@end