ios - 如何从 TableView 中删除行？

Question

我尝试了很多，但无法帮助我摆脱这种情况

//
//  TableViewController.m
//  jsonplaceholder
//
//  Created by manikandan on 19/04/16.
//  Copyright (c) 2016 manikandan. All rights reserved.
//

#import "TableViewController.h"
#import "TableViewCell.h"
#import "DetailViewController.h"

@interface TableViewController ()
<NSURLConnectionDelegate>
{
    NSString *string;
    NSURL *url;
    NSURLRequest *request;
    NSURLConnection *connection;
    NSMutableData *receivedata;

    NSString *imgstring;
    NSURL *imgurl;

    NSMutableData *imgreceivedata;

       NSMutableArray *dictarry;
     NSMutableArray *dictarry1;
     NSMutableArray *dictarry2;
     NSMutableArray *deldictarray;
     NSMutableArray *deldictarray1;
     NSMutableArray *deldictarray2;

    NSMutableDictionary *dict;
    int a;
}

@end

@implementation TableViewController

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {

    }
    return self;
}

- (void)viewDidLoad
{

        [super viewDidLoad];
        string =@"http://jsonplaceholder.typicode.com/posts";
        url = [NSURL URLWithString:string];
        request=[NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
        connection =[NSURLConnection connectionWithRequest:request delegate:self];
        receivedata =[NSMutableData data];
        NSLog(@"hai");
       imgstring = @"http://2.bp.blogspot.com/-uhWTslN7wO8/UdXSIswnW4I/AAAAAAAACWo/Y10XXAfoGI4/s575/AJITH-OPTIMIZATION+(10).jpg";
        imgurl =[NSURL URLWithString:imgstring];
        imgreceivedata = [NSData dataWithContentsOfURL:imgurl];

}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    [receivedata setLength:0];
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{

    [receivedata appendData:data];

}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    dict=[NSJSONSerialization JSONObjectWithData:receivedata options:NSJSONReadingAllowFragments error:nil];
    NSLog(@"%@",dict);
    dictarry =[dict valueForKey:@"id"];
    dictarry1 =[dict valueForKey:@"title"];
    dictarry2 =[dict valueForKey:@"body"];
    a=[dictarry count];
    NSLog(@"%d",a);
    NSLog(@"%@",dictarry);
    NSLog(@"%@",dictarry1);
    NSLog(@"%@",dictarry2);
    [self.tableView reloadData];

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}



- (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 a;

}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *Cellid=@"Cell";
    TableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:Cellid forIndexPath:indexPath];


   cell.lbltitle.text=[NSString stringWithFormat:@"%@",[dictarry objectAtIndex:indexPath.row ]];
    cell.lblsubtitle .text=[dictarry1 objectAtIndex:indexPath.row];
    cell.lbldescription.text=[dictarry2 objectAtIndex:indexPath.row];
    cell.imgview .image=[UIImage imageWithData:imgreceivedata];

    return cell;
}


-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    DetailViewController *detail =[self.storyboard instantiateViewControllerWithIdentifier:@"detail"];

    detail.passstring1=[[dictarry objectAtIndex:indexPath.row] stringValue] ;
    detail.passstring2=[dictarry1 objectAtIndex:indexPath.row];
    detail.passstring3=[dictarry2 objectAtIndex:indexPath.row];
    detail.passstring4=imgreceivedata;

    [self.navigationController pushViewController:detail  animated:YES];

}



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

  /* code problem here i can't  resolve it kindly help me.`enter code here`*/
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {

 // I  just create 3 array to transfer value    

    a=a-1;

    deldictarray=[[NSMutableArray alloc]initWithArray:dictarry];
    deldictarray1=[[NSMutableArray alloc]initWithArray:dictarry1];
    deldictarray2=[[NSMutableArray alloc]initWithArray:dictarry2];

    [deldictarray1 removeObjectAtIndex:[indexPath row]];
    [deldictarray2 removeObjectAtIndex:[indexPath row ]];
    [deldictarray removeObjectAtIndex:[indexPath row]];

   [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
   dictarry=[[NSMutableArray alloc]initWithArray:deldictarray];
   dictarry1=[[NSMutableArray alloc]initWithArray:deldictarray1];
    dictarry2=[[NSMutableArray alloc]initWithArray:deldictarray2];
    NSLog(@"%lu",(unsigned long)[dictarry count]);
                 [self.tableView reloadData];



    } 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
    }   
}


@end

//这里我也附上了我的日志报告

2016-04-21 10:51:27.046 jsonplaceholder[469:60b] -[NSArrayI removeObjectAtIndex:]: unrecognized selector sent to instance 0x8c3c650 2016-04-21 10:51:27.137 jsonplaceholder[469:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI removeObjectAtIndex:]: unrecognized selector sent to instance 0x8c3c650' *** First throw call stack: ( 0 CoreFoundation 0x017f11e4 __exceptionPreprocess + 180 1 libobjc.A.dylib
0x015708e5 objc_exception_throw + 44 2 CoreFoundation
0x0188e243 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275 3
CoreFoundation 0x017e150b ___forwarding_ + 1019 4 CoreFoundation 0x017e10ee _CF_forwarding_prep_0 + 14 5 jsonplaceholder 0x00003d02 -[TableViewController tableView:commitEditingStyle:forRowAtIndexPath:] + 178 6 UIKit
0x0032a6a3 -[UITableView animateDeletionOfRowWithCell:] + 107 7
UIKit 0x004b3595 -[UITableViewCell _swipeDeleteButtonPushed] + 70 8 libobjc.A.dylib 0x01582880 -[NSObject performSelector:withObject:withObject:] + 77 9 UIKit 0x002323b9 -[UIApplication sendAction:to:from:forEvent:] + 108 10 UIKit
0x00232345 -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 61 11 UIKit 0x00333bd1 -[UIControl sendAction:to:forEvent:] + 66 12 UIKit
0x00333fc6 -[UIControl _sendActionsForEvents:withEvent:] + 577 13 UIKit 0x00333243 -[UIControl touchesEnded:withEvent:] + 641 14 UIKit
0x005c82e3 _UIGestureRecognizerUpdate + 7166 15 UIKit
0x00271a5a -[UIWindow _sendGesturesForEvent:] + 1291 16 UIKit
0x00272971 -[UIWindow sendEvent:] + 1021 17 UIKit
0x002445f2 -[UIApplication sendEvent:] + 242 18 UIKit
0x0022e353 _UIApplicationHandleEventQueue + 11455 19 CoreFoundation 0x0177a77f CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 15 20 CoreFoundation 0x0177a10b __CFRunLoopDoSources0 + 235 21 CoreFoundation 0x017971ae __CFRunLoopRun + 910 22 CoreFoundation
0x017969d3 CFRunLoopRunSpecific + 467 23 CoreFoundation
0x017967eb CFRunLoopRunInMode + 123 24 GraphicsServices
0x037e55ee GSEventRunModal + 192 25 GraphicsServices
0x037e542b GSEventRun + 104 26 UIKit
0x00230f9b UIApplicationMain + 1225 27 jsonplaceholder
0x0000411d main + 141 28 libdyld.dylib
0x01e3870d start + 1 ) libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)

Answer 1

首先:Objective-C 是一种面向对象的语言。使用自定义类而不是三个数组作为数据源。

要解决您的问题，请忘记 a 变量并始终返回 dictarry 中的项目数

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return dictarry.count;
}

并在 commitEditingStyle 中删除重新加载 TableView 的行，因为 deleteRowsAtIndexPaths 会自动重新排 ListView 。

编辑

您的崩溃日志显示三个数据源数组是不可变的。尽管它们被声明为 NSMutabeArray，但 KVC 方法 valueForKey: 返回一个不可变数组。更改这三行:

dictarry = [[dict valueForKey:@"id"] mutableCopy];
dictarry1 = [[dict valueForKey:@"title"] mutableCopy];
dictarry2 = [[dict valueForKey:@"body"] mutableCopy];