為什么我得到錯誤“[UIViewController tableView：numberOfRowsInSection：]：無法識別的選擇器發送到實例0x4e38c50'”？

Question

我制作了一個TabBarApplication，並制作了3個控制器，其中1個是繼承UITableViewController，我將部分的數量設為“返回1”，部分中的行數為“返回2”，

我遇到以下問題，為什么？

[UIViewController tableView:numberOfRowsInSection:]:無法識別的選擇器發送到實例0x4e38c50'“

#import <UIKit/UIKit.h>


@interface List : UITableViewController {

}

@end

和.m文件是

    #import "List.h"


    @implementation List


    #pragma mark -
    #pragma mark View lifecycle

/*
- (void)viewDidLoad {
    [super viewDidLoad];

    // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
    // self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
*/

/*
- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
}
*/
/*
- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
}
*/
/*
- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
}
*/
/*
- (void)viewDidDisappear:(BOOL)animated {
    [super viewDidDisappear:animated];
}
*/
/*
// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    // Return YES for supported orientations.
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
*/


#pragma mark -
#pragma mark Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    // Return the number of sections.
    return 1;
}


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    // Return the number of rows in the section.
    return 10;
}


// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }

    // Configure the cell...

    return cell;
}


/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath {
    // Return NO if you do not want the specified item to be editable.
    return YES;
}
*/


/*
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

    if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete the row from the data source.
        [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }   
    else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view.
    }   
}
*/


/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath {
}
*/


/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath {
    // Return NO if you do not want the item to be re-orderable.
    return YES;
}
*/


#pragma mark -
#pragma mark Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    // Navigation logic may go here. Create and push another view controller.
    /*
    <#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];
    // ...
    // Pass the selected object to the new view controller.
    [self.navigationController pushViewController:detailViewController animated:YES];
    [detailViewController release];
    */
}


#pragma mark -
#pragma mark Memory management

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Relinquish ownership any cached data, images, etc. that aren't in use.
}

- (void)viewDidUnload {
    // Relinquish ownership of anything that can be recreated in viewDidLoad or on demand.
    // For example: self.myOutlet = nil;
}


- (void)dealloc {
    [super dealloc];
}


@end

Answer 1

請檢查tableView的數據源。 我認為它沒有正確設置。 如果未正確設置dataSource，則可能會導致問題

Answer 2

當您設置未實現delegate/datasource protocol上聲明的方法的表視圖delegate/datasource ，會發生這種情況。

沒有查看代碼，我無法准確地告訴你你做錯了什么，但是如果你使用xcode模板創建控制器，那么只需要將它初始化為UITableViewController而UIVIewController一般的UIVIewController 。

如果你發布你的代碼我可以幫你解決什么錯誤，但正如我所說，當tableview委托沒有實現tableView:numberOfRowsInSection:時會發生這個錯誤tableView:numberOfRowsInSection: method; 如果你說你正在實現這個方法，那么tableview沒有被分配鏈接到那個控制器類..

Answer 3

好吧，我一直都在犯這個錯誤。 在Outlets下，確保將插座拖到“ViewController”而不是“View”。 我通常使用“文檔大綱”進行連接以確保。 希望這可以幫助。

Answer 4

我得到了同樣的錯誤。 我通過將View Controller的類從UIViewController更改為ViewController（您的視圖控制器類ViewController.h）來解決它