Question

我有2个TableViewControllers。当用户点击UIBarButtonItem时，它会在SaveViewController中保存来自UITextField，runnameField的文本。它应该采用runnameField的文本并将其放在一个数组，runsArray中。在RecordVC中，tableView的数据应来自runsArray。有人可以帮我这个吗？我一直在谷歌上搜索，找不到任何答案。

SaveViewController.h：

#import <UIKit/UIKit.h>
#import "RecordsViewController.h" //Next ViewController

@interface SaveViewController : UITableViewController <UITableViewDataSource,UITableViewDelegate> {
__weak IBOutlet UITextField *runnameField;
RecordsViewController *RecordsVCData;
}
@property (weak, nonatomic) IBOutlet UITextField *runnameField;
@property (weak, nonatomic) IBOutlet UITextView *runnotesTextView;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *saveBarItem;
@property (nonatomic, retain) RecordsViewController *RecordsVCData;

- (IBAction)saverun:(UIBarButtonItem *)sender;
- (IBAction)goAwayKeyboard:(id)sender;



@end

SaveViewController.m：

- (IBAction)saverun:(UIBarButtonItem *)sender {
RecordsViewController *RecordsVC = [[RecordsViewController alloc] initWithNibName:nil bundle:nil];
RecordsVC.tableView = [[UITableView alloc] initWithFrame:CGRectZero style:UITableViewStyleGrouped];
self.RecordsVCData = RecordsVC;
[RecordsVC.runsArray addObject:[NSString stringWithFormat:@"%@", runnameField.text]];
[self presentModalViewController:RecordsVC animated:YES];
}

- (IBAction)goAwayKeyboard:(id)sender {
    [sender resignFirstResponder];
}

RecordsViewController.h：

#import <UIKit/UIKit.h>
@interface RecordsViewController : UITableViewController <UITableViewDataSource, UITableViewDelegate> {      
NSMutableArray *runsArray;
}
@property (weak, nonatomic) NSString *runname;
@property (strong, nonatomic) NSString *runnotes;
@property (weak, nonatomic) UITableViewCell *cell;
@property (retain,nonatomic) NSMutableArray *runsArray;
@end

RecordsViewController.m：

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:     (NSIndexPath *)indexPath {

// Identifier for retrieving reusable cells.
static NSString *cellIdentifier = @"MyCellIdentifier";

// Attempt to request the reusable cell.

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault     reuseIdentifier:cellIdentifier];
// No cell available - create one
if(cell == nil) {
    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
                                  reuseIdentifier:cellIdentifier];
[cell.textLabel setText:[NSString stringWithFormat:@"%@",[runsArray objectAtIndex:indexPath.row]]];

}

// Set the text of the cell to the runnamestring.
[cell.textLabel setText:[NSString stringWithFormat:@"%@",[runsArray objectAtIndex:indexPath.row]]];
return cell;

}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [runsArray count];
}

任何帮助都值得赞赏。

谢谢，

Dhruv直升机

Answer 1

在你更新RecordsVC.runsArray的时候，我想你的tableview已经被初始化和加载了，虽然没有数据。

我最近在这种情况下所做的就是使用通知。

在您的RecordsViewController中，您将在init方法中注册通知：

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {

        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(dataLoaded:) name:@"runsArrayLoaded" object:nil];

        // Custom initialization
    }
    return self;
}

同样在RecordsViewController中，您将需要在收到通知时调用的方法。在这种情况下，它是dataLoaded：

-(void) dataLoaded:(NSNotification *)notif {
    if (notif.userInfo){
        runsArray = [notif.userInfo objectForKey:@"newdata"];
        [self.tableview reloadData];
    }
}

使所有这些神奇工作的部分在SaveViewController类中的saverun方法中。

- (IBAction)saverun:(UIBarButtonItem *)sender {
    RecordsViewController *RecordsVC = [[RecordsViewController alloc] initWithNibName:nil bundle:nil];
    RecordsVC.tableView = [[UITableView alloc] initWithFrame:CGRectZero style:UITableViewStyleGrouped];
    [runsArray addObject:[NSString stringWithFormat:@"%@", runnameField.text]];
    [self presentModalViewController:RecordsVC animated:YES];

    // notify the RecordsViewController that new data is available
    NSMutableDictionary* userInfo = [[NSMutableDictionary alloc] initWithCapacity:1];
    [userInfo setObject:runsArray forKey:@"newdata"];
    [[NSNotificationCenter defaultCenter] postNotificationName:@runsArrayLoaded" object:nil userInfo:(NSDictionary*)userInfo];
}

最后，您必须清理并删除RecordsViewController类中的通知观察。在viewWillDisappear中，添加以下行：

[[NSNotifcation defaultCenter] removeObserver:self name:@"runsArrayLoaded" object:nil];

从先前视图控制器中的数组获取数据，将其放入另一个TableViewController中

1 个答案: