iOS -- Segue 傳入

使用 SEGUE 輸出與輸入資料

e.g. RootViewController 是一TableViewController，將Cell的值傳入DetailViewController。然後，在DetailVC 的TextView編輯好的資料，在回傳入RootViewController上頭的Cell，改變Cell 的值.


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RootViewContrller.h 裡要設一 NSDictionary *returnSelection; 來接收回傳的值
RootViewController.m:

//傳資料到DetailController 

- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    

    UIViewController *destination = segue.destinationViewController;//將segue的目的控制器指定給destination

    

    //第一個if是回傳時用的

    if ([destination respondsToSelector:@selector(setDelegate:)]) { //如果對setDelegate:方法有反應，便將自己存成value,設key為delegate

        [destination setValue:self forKey:@"delegate"];

    }

    

    //第二個if是傳出用的

    if ([destination respondsToSelector:@selector(setMySelection:)]) {//如果對setSelection:方法有反應,請準備處理選擇後的值

        

        //prepare selection info

        

        NSIndexPath *indexPath = [self.table indexPathForCell:sender];//將選擇的行列指定給indexPath

        id object = [self.arr objectAtIndex:indexPath.row];//取出入徑索引的物件，指定予object

        NSDictionary *mySelection = [NSDictionary dictionaryWithObjectsAndKeys:indexPath, @"indexPath", object, @"object", nil]; //將其入徑索引和物件存入到一個dictionary

        [destination setValue:mySelection forKey:@"mySelection"];//設定下一個控制器的KVC

    }

}

//Setter: 取得來自DetailController的回傳delegate

- (void) setReturnSelection:(NSDictionary *)dict {

    

    if (![dict isEqual:returnSelection]) {

        

        returnSelection = dict;

        NSIndexPath *indexPath = [dict objectForKey:@"indexPath"];

        id newValue = [dict objectForKey:@"object"];

        [tasks replaceObjectAtIndex:indexPath.row withObject:newValue];

        [self.tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];

    }

}

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DetailViewContoller.h 要設 id delegate;

DetailViewController.m

//接收root傳來的值

- (void)viewDidLoad

{

    [super viewDidLoad];

NSString *voc = [mySelection objectForKey:@"object"];

}

//回傳到root：

- (void) viewWillDisappear:(BOOL)animated {

    

    [super viewWillDisappear:animated];

    

    if ([delegate respondsToSelector:@selector(setReturnSelection:)]) {

        

        //finish editing

        [textView endEditing:YES];

        //prepare selection info

        NSIndexPath *indexPath = [mySelection objectForKey:@"indexPath"];//回傳到正確的Cell Row

        id object = textView.text;

        NSDictionary *returnSelection = [NSDictionary dictionaryWithObjectsAndKeys:indexPath, @"indexPath", object, @"object", nil];

        

        

        [delegate setValue:returnSelection forKey:@"returnSelection"];

        

    }

}

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Xcode 的樣板

這裡的 data 只是單存的 array:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender

{

    if ([[segue identifier] isEqualToString:@"showDetail"]) {

        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];

        

       NSDate *object = [_objects objectAtIndex:indexPath.row];

        

        [[segue destinationViewController] setDetailItem:object];

    }

}