Question

好的，所以我最近帮助Darren解决了我的tableview数据没有显示的问题。我将在这里留下一份文件，我将会受到影响。

在故事板中，最后有3个对象，其中2个根据tableView上选择的项目自动更改。我想添加另一个标签（在项目中已经做过），并根据在表格视图中选择的项目，这里会显示一些信息。就像其他2一样。

我该怎么做？

对于那些不信任下载文件的人，我得到了一些可能有帮助的代码..我希望在带有标记＃3的标签中显示“myData2”。我怎么能这样做？

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Define our test data
    myData = [NSMutableArray arrayWithObjects:
              @"Chasing Amy", 
              @"Mallrats", 
              @"Dogma", 
              @"Clerks", 
              @"Jay & Silent Bob Strike Back",
              @"Red State",
              @"Cop Out",
              @"Jersey Girl",
              nil];

    //test for 2nd data
    myData2 = [NSMutableArray arrayWithObjects:
              @"Info for Chasing Amy item",
              @"Info for Mallrats",
              @"Info for Dogma",
              @"Info for Clerks",
              @"Info for Jay & Silent Bob Strike Back",
              @"Info for Red State",
              @"Info for Cop Out",
              @"Info for Jersey Girl",
              nil];
}

// Return number of sections in table (always 1 for this demo!)
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

// Return the amount of items in our table (the total items in our array above)
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [myData count];
    return [myData2 count];
}

// Return a cell for the table
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // A cell identifier which matches our identifier in IB
    static NSString *CellIdentifier = @"CellIdentifier";

    // Create or reuse a cell
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    // Get the cell label using it's tag and set it
    UILabel *cellLabel = (UILabel *)[cell viewWithTag:1];
    [cellLabel setText:[myData objectAtIndex:indexPath.row]];

    // get the cell imageview using it's tag and set it
    UIImageView *cellImage = (UIImageView *)[cell viewWithTag:2];
    [cellImage setImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.jpg", indexPath.row]]];

    return cell;
}

// Do some customisation of our new view when a table item has been selected
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Make sure we're referring to the correct segue
    if ([[segue identifier] isEqualToString:@"ShowSelectedMovie"]) {

        // Get reference to the destination view controller
        Tab2_ItemViewController *vc = [segue destinationViewController];

        // get the selected index
        NSInteger selectedIndex = [[self.tableView indexPathForSelectedRow] row];

        // Pass the name and index of our film
        [vc setSelectedItem:[NSString stringWithFormat:@"%@", [myData objectAtIndex:selectedIndex]]];
        [vc setSelectedIndex:selectedIndex];

        //
        [vc setSelectedItem:[NSString stringWithFormat:@"%@", [myData2 objectAtIndex:selectedIndex]]];
        [vc setSelectedIndex:selectedIndex];
    }
}

@end

现在我得到一个断点：

Download File (3.12mb)

#import "Tab2_TableViewController.h"
#import "Tab2_ItemViewController.h"

@implementation Tab2_TableViewController

// When the view loads, define our data
- (void)viewDidLoad
{
    [super viewDidLoad];

    // Define our test data
    myData = [NSMutableArray arrayWithObjects:
              @"Chasing Amy",
              @"Mallrats",
              @"Dogma",
              @"Clerks",
              @"Jay &amp; Silent Bob Strike Back",
              @"Red State",
              @"Cop Out",
              @"Jersey Girl",
              nil];

    // Define our test data2
    myData2 = [NSMutableArray arrayWithObjects:
              @"info Chasing Amy",
              @"info Mallrats",
              @"info Dogma",
              @"info Clerks",
              @"info Jay &amp; Silent Bob Strike Back",
              @"info Red State",
              @"info Cop Out",
              @"info Jersey Girl",
              nil];
}



// Return the amount of items in our table (the total items in our array above)
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [myData count];
    return [myData2 count];
}

// Return number of sections in table (always 1 for this demo!)
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

// Return a cell for the table
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // A cell identifier which matches our identifier in IB
    static NSString *CellIdentifier = @"CellIdentifier";

    // Create or reuse a cell
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    // Get the cell label using its tag and set it
    UILabel *cellLabel = (UILabel *)[cell viewWithTag:1];
    [cellLabel setText:[myData objectAtIndex:indexPath.row]];

    // Get the cell label2 using its tag and set it
    UILabel *cellLabelInfo = (UILabel *)[cell viewWithTag:3];
    [cellLabelInfo setText:[myData2 objectAtIndex:indexPath.row]];

    // get the cell imageview using its tag and set it
    UIImageView *cellImage = (UIImageView *)[cell viewWithTag:2];
    [cellImage setImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.jpg", indexPath.row]]];

    return cell;
}

// Do some customisation of our new view when a table item has been selected
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Make sure we're referring to the correct segue
    if ([[segue identifier] isEqualToString:@"ShowSelectedMovie"]) {

        // Get reference to the destination view controller
        Tab2_ItemViewController *vc = [segue destinationViewController];

        // get the selected index
        NSInteger selectedIndex = [[self.tableView indexPathForSelectedRow] row];

        // Pass the name and index of our film
        [vc setSelectedItem:[NSString stringWithFormat:@"%@", [myData objectAtIndex:selectedIndex]]];
        [vc setSelectedIndex:selectedIndex];
        [vc setSelectedItemInfo:[NSString stringWithFormat:@"%@", [myData2 objectAtIndex:selectedIndex]]];
    }
}

@end

断点位于最小行“[vc setSelectedItemInfo：[NSString stringWithFormat：@”％@“，[myData2 objectAtIndex：selectedIndex]]];”

Answer 1

您需要在Tab2_ItemViewController中创建一个新属性（而不是selectedItem，请使用say selectedItemInfo）。您还需要一个新的IBOutlet连接到您要更新的标签。然后使用：

传递数据

[vc setSelectedItemInfo:[NSString stringWithFormat:@"%@", [myData2 objectAtIndex:selectedIndex]]];

这与您传递其他标签的数据完全类似。

我从你的链接下载了代码，它并没有让我崩溃。它正确设置了您创建的新属性。尽管如此，outputLabelInfo UILabel的IBOutlet并没有连接到故事板。你需要把它搞定。然后，您需要通过更改：

来修复此标签中文本的设置方式

 [outputLabel setText:selectedItemInfo];

到

[outputLabelInfo setText:selectedItemInfo];

在Tab2_ItemViewController.m代码中。尝试这样做，清理项目并再次运行。

Answer 2

顺便说一句，看看你的cellForRowAtIndexPath，你有一些奇怪的结构。

如果您没有使用单元格原型，但是您使用自己的控件，则必须在创建单元格时创建它们，例如：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // A cell identifier which matches our identifier in IB
    static NSString *CellIdentifier = @"CellIdentifier";

    // Create or reuse a cell
    UILabel *cellLabel;
    UILabel *cellLabelInfo;
    UIImageView *cellImage;

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
        cellLabel = [[UILabel alloc] init...];
        cellLabel.tag = 1;
        cellLabelInfo = [[UILabel alloc] init...];
        cellLabelInfo.tag = 3; 
        cellImage = [[UIImageView alloc] init...];
        cellImage.tag = 2;
    }
    else
    {
        cellLabel = (UILabel *)[cell viewWithTag:1];
        cellLabelInfo = (UILabel *)[cell viewWithTag:3];
        cellImage = (UIImageView *)[cell viewWithTag:2];
    }

    // Get the cell label using its tag and set it
    [cellLabel setText:[myData objectAtIndex:indexPath.row]];

    // Get the cell label2 using its tag and set it
    [cellLabelInfo setText:[myData2 objectAtIndex:indexPath.row]];

    // get the cell imageview using its tag and set it
    [cellImage setImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.jpg", indexPath.row]]];

    return cell;
}

我将详细介绍如何以编程方式创建三个控件，但希望您能得到这个想法。您在创建单元格时创建任何自定义控件（并设置其各自的tag属性），如果您成功将单元格出列，则只需要引用这些子视图。

说实话，如果您只处理图片，标题和副标题，我会倾向于使用标准UITableViewCell样式并使用其textLabel，detailTextLabel和imageView属性，而不是对单元格进行任何自定义。如果我执行自定义，我会使用单元格原型和自定义子类，这样就无需手动创建控件和/或使用viewWithTag手动检索对它们的引用。

TableView添加一个自动更改的新Label

2 个答案: