如何从Xib文件加载自定义UITableViewCells？

左手的ㄟ右手 2023-03-04 08:10 166阅读 0赞

本文翻译自：[How do you load custom UITableViewCells from Xib files?][How do you load custom UITableViewCells from Xib files]

*The question is simple: How do you load custom `UITableViewCell` from Xib files?* **问题很简单：如何从Xib文件加载自定义`UITableViewCell` ？** *Doing so allows you to use Interface Builder to design your cells.* **这样做允许您使用Interface Builder来设计单元格。** *The answer apparently is not simple due to memory managment issues.* **由于内存管理问题，答案显然并不简单。** *[This thread][] mentions the issue and suggests a solution, but is pre NDA-release and lacks code.* **[这个主题][This thread]提到了这个问题并建议了一个解决方案，但是在NDA发布之前并且没有代码。** *Here's a [long thread][] that discusses the issue without providing a definitive answer.* **这是一个[很长的线程][long thread] ，在没有提供明确答案的情况下讨论了这个问题。**

*Here's some code I've used:* **这是我用过的一些代码：**

static NSString *CellIdentifier = @"MyCellIdentifier";
    
    MyCell *cell = (MyCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        NSArray *nib = [[NSBundle mainBundle] loadNibNamed:CellIdentifier owner:self options:nil];
        cell = (MyCell *)[nib objectAtIndex:0];
    }

*To use this code, create MyCell.m/.h, a new subclass of `UITableViewCell` and add `IBOutlets` for the components you want.* **要使用此代码，请创建MyCell.m / .h， `UITableViewCell`的新子类，并为所需的组件添加`IBOutlets` 。** *Then create a new "Empty XIB" file.* **然后创建一个新的“空XIB”文件。** *Open the Xib file in IB, add a `UITableViewCell` object, set its identifier to "MyCellIdentifier", and set its class to MyCell and add your components.* **在IB中打开Xib文件，添加`UITableViewCell`对象，将其标识符设置为“MyCellIdentifier”，并将其类设置为MyCell并添加组件。** *Finally, connect the `IBOutlets` to the components.* **最后，将`IBOutlets`连接到组件。** *Note that we did not set the File's Owner in IB.* **请注意，我们没有在IB中设置文件所有者。**

*Other methods advocate setting the File's Owner and warn of memory leaks if the Xib is not loaded via an additional factory class.* **如果未通过其他工厂类加载Xib，则其他方法主张设置文件所有者并警告内存泄漏。** *I tested the above under Instruments/Leaks and saw no memory leaks.* **我在Instruments / Leaks下测试了上面的内容，没有发现内存泄漏。**

*So what's the canonical way to load cells from Xibs?* **那么从Xibs加载单元格的规范方法是什么？** *Do we set File's Owner?* **我们设置文件的所有者吗？** *Do we need a factory?* **我们需要工厂吗？** *If so, what's the code for the factory look like?* **如果是这样，工厂的代码是什么样的？** *If there are multiple solutions, let's clarify the pros and cons of each of them...* **如果有多种解决方案，让我们澄清每种解决方案的优缺点......**

--------------------

### \#1楼 ###

参考：[https://stackoom.com/question/2gzf/如何从Xib文件加载自定义UITableViewCells][https_stackoom.com_question_2gzf_Xib_UITableViewCells]

--------------------

### \#2楼 ###

*The correct way to do it is to create a UITableViewCell subclass implementation, header, and XIB.* **正确的方法是创建UITableViewCell子类实现，标头和XIB。** *In the XIB remove any views and just add a table cell.* **在XIB中删除任何视图，只需添加一个表格单元格。** *Set the class as the name of the UITableViewCell subclass.* **将类设置为UITableViewCell子类的名称。** *For file owner, make it the UITableViewController subclass class name.* **对于文件所有者，使其成为UITableViewController子类的类名。** *Connect the file owner to the cell using the tableViewCell outlet.* **使用tableViewCell插座将文件所有者连接到单元。**

*In the header file:* **在头文件中：**

UITableViewCell *_tableViewCell;
    @property (assign) IBOutlet UITableViewCell *tableViewCell;

*In the implementation file:* **在实现文件中：**

@synthesize tableViewCell = _tableViewCell;
    
    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
        static NSString *kCellIdentifier = @"reusableCell";
    
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellIdentifier];
        if (cell == nil) {
            [[NSBundle mainBundle] loadNibNamed:kCellIdentifier owner:self options:nil];
            cell = _tableViewCell;
            self.tableViewCell = nil;
        }
    
        return cell;
    }

--------------------

### \#3楼 ###

*The right solution is this:* **正确的解决方案是：**

- (void)viewDidLoad
    {
        [super viewDidLoad];
        UINib *nib = [UINib nibWithNibName:@"ItemCell" bundle:nil];
        [[self tableView] registerNib:nib forCellReuseIdentifier:@"ItemCell"];
    }
    
    -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    {
        // Create an instance of ItemCell
        PointsItemCell *cell = [tableView dequeueReusableCellWithIdentifier:@"ItemCell"];
    
        return cell;
    }

--------------------

### \#4楼 ###

*Check this - [http://eppz.eu/blog/custom-uitableview-cell/][http_eppz.eu_blog_custom-uitableview-cell] \- really convenient way using a tiny class that ends up one line in controller implementation:* **检查一下 - [http://eppz.eu/blog/custom-uitableview-cell/][http_eppz.eu_blog_custom-uitableview-cell] \- 使用一个在控制器实现中结束一行的小类非常方便的方法：**

-(UITableViewCell*)tableView:(UITableView*) tableView cellForRowAtIndexPath:(NSIndexPath*) indexPath
    {
        return [TCItemCell cellForTableView:tableView
                              atIndexPath:indexPath
                          withModelSource:self];
    }

![在此输入图像描述][TZEB3.png]

--------------------

### \#5楼 ###

*I've decided to post since I don't like any of these answers -- things can always be more simple and this is by far the most concise way I've found.* **我决定发帖，因为我不喜欢任何这些答案 - 事情总是更简单，这是迄今为止我发现的最简洁的方式。**

***1. Build your Xib in Interface Builder as you like it*** **1.根据需要在Interface Builder中构建Xib**

*  *Set File's Owner to class NSObject* **将File的Owner设置为NSObject类**
 *  *Add a UITableViewCell and set its class to MyTableViewCellSubclass -- if your IB crashes (happens in Xcode > 4 as of this writing), just use a UIView of do the interface in Xcode 4 if you still have it laying around* **添加一个UITableViewCell并将其类设置为MyTableViewCellSubclass - 如果您的IB崩溃（在撰写本文时Xcode> 4中发生），只需使用UIView在Xcode 4中执行该接口，如果您仍然存在它**
 *  *Layout your subviews inside this cell and attach your IBOutlet connections to your @interface in the .h or .m (.m is my preference)* **在此单元格内布置子视图，并将您的IBOutlet连接附加到.h或.m中的@interface（.m是我的偏好）**

***2. In your UIViewController or UITableViewController subclass*** **2.在UIViewController或UITableViewController子类中**

@implementation ViewController
    
    static NSString *cellIdentifier = @"MyCellIdentier";
    
    - (void) viewDidLoad {
    
        ...
        [self.tableView registerNib:[UINib nibWithNibName:@"MyTableViewCellSubclass" bundle:nil] forCellReuseIdentifier:cellIdentifier];
    }
    
    - (UITableViewCell*) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    {
        MyTableViewCellSubclass *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    
        ...
    
        return cell;
    }

***3. In your MyTableViewCellSubclass*** **3.在MyTableViewCellSubclass中**

- (id) initWithCoder:(NSCoder *)aDecoder {
        if (self = [super initWithCoder:aDecoder]) {
            ...
        }
    
        return self;
    }

--------------------

### \#6楼 ###

*Here are two methods which the [original author states was recommended by an IB engineer][] .* **以下是[IB工程师推荐的][original author states was recommended by an IB engineer]两种[原始作者][original author states was recommended by an IB engineer]所述的方法。**

*See the actual post for more details.* **有关详细信息，请参阅实际帖子。** *I prefer method \#2 as it seems simpler.* **我更喜欢方法＃2，因为它似乎更简单。**

***Method \#1:*** **方法＃1：**

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"BDCustomCell"];
        if (cell == nil) {
            // Create a temporary UIViewController to instantiate the custom cell.
            UIViewController *temporaryController = [[UIViewController alloc] initWithNibName:@"BDCustomCell" bundle:nil];
            // Grab a pointer to the custom cell.
            cell = (BDCustomCell *)temporaryController.view;
            [[cell retain] autorelease];
            // Release the temporary UIViewController.
            [temporaryController release];
        }
    
        return cell;
    }

***Method \#2:*** **方法＃2：**

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"BDCustomCell"];
        if (cell == nil) {
            // Load the top-level objects from the custom cell XIB.
            NSArray *topLevelObjects = [[NSBundle mainBundle] loadNibNamed:@"BDCustomCell" owner:self options:nil];
            // Grab a pointer to the first object (presumably the custom cell, as that's all the XIB should contain).
            cell = [topLevelObjects objectAtIndex:0];
        }
    
        return cell;
    }

***Update (2014):** Method \#2 is still valid but there is no documentation for it anymore.* **更新（2014）：方法＃2仍然有效，但不再有文档。** *It used to be in the [official docs][] but is now removed in favor of storyboards.* **它曾经在[官方文档中，][official docs]但现在被删除，有利于故事板。**

*I posted a working example on Github:* **我在Github上发布了一个工作示例：**  
*[https://github.com/bentford/NibTableCellExample][https_github.com_bentford_NibTableCellExample]* **[https://github.com/bentford/NibTableCellExample][https_github.com_bentford_NibTableCellExample]**

***edit for Swift 4.2*** **编辑Swift 4.2**

override func viewDidLoad() {
        super.viewDidLoad()
    
        // Do any additional setup after loading the view.
        self.tblContacts.register(UINib(nibName: CellNames.ContactsCell, bundle: nil), forCellReuseIdentifier: MyIdentifier)
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    
        let cell = tableView.dequeueReusableCell(withIdentifier: MyIdentifier, for: indexPath) as! ContactsCell
    
        return cell
    }

[How do you load custom UITableViewCells from Xib files]: https://oldbug.net/q/2gzf/How-do-you-load-custom-UITableViewCells-from-Xib-files
[This thread]: https://stackoverflow.com/questions/134575/using-interface-builder-for-uitableviews
[long thread]: http://discussions.apple.com/thread.jspa?messageID=8040526&tstart=0
[https_stackoom.com_question_2gzf_Xib_UITableViewCells]: https://stackoom.com/question/2gzf/%E5%A6%82%E4%BD%95%E4%BB%8EXib%E6%96%87%E4%BB%B6%E5%8A%A0%E8%BD%BD%E8%87%AA%E5%AE%9A%E4%B9%89UITableViewCells
[http_eppz.eu_blog_custom-uitableview-cell]: http://eppz.eu/blog/custom-uitableview-cell/
[TZEB3.png]: https://i.stack.imgur.com/TZEB3.png
[original author states was recommended by an IB engineer]: http://www.bdunagan.com/2009/06/28/custom-uitableviewcell-from-a-xib-in-interface-builder/
[official docs]: https://developer.apple.com/documentation/uikit/views_and_controls/table_views?language=objc
[https_github.com_bentford_NibTableCellExample]: https://github.com/bentford/NibTableCellExample