Question

i have two view controllers, GroupListViewController and GroupDetailViewController, switch back and forth, When switch forth by click the row cell,
Run with error, I do not have xib even. i do all component programmatically. search with the same question in here, it is not my type.

in code snippet below, “CustomGroupListViewCell *plcc” CustomGroupListViewCell is a custom UITableViewCell, you can implement a dump one with empty,

list the code here.

GroupListViewController.h

#import <UIKit/UIKit.h>


@class GroupDetailViewController;

@interface GroupListViewController : UITableViewController
{
    NSArray * contentArray;
    GroupDetailViewController * dvController;
}

@property (nonatomic, retain) GroupDetailViewController * dvController;

@end

GroupListViewController.m

#import "GroupListViewController.h"
#import "CustomGroupListViewCell.h"
#import "ZYAppDelegate.h"
#import "GroupDetailViewController.h"

@interface GroupListViewController ()
@end

@implementation GroupListViewController

@synthesize dvController;

- (void) viewDidLoad
{
contentArray = [[NSArray arrayWithObjects:@"heyun", @"wushi", @"ios", nil]retain];

[super viewDidLoad];

}


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
    // Custom initialization
    }  
    return self;
}

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

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

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear: animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear: animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear: animated];
}

- (void)viewDisDisappear:(BOOL)animated
{
    [super viewDidDisappear: animated];
}

- (NSInteger)numberOfSectionsInTableView: (UITableView *)tableView
{
    return 1;
} 

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{

    return [contentArray count];
}

// custom row height
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // dynamic with whether the cell has the gourp image or not..
    return 160;
}

// Customize the appearance of table view cells
- (UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"PartyListCustomCell";

    CustomGroupListViewCell *plcc = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if(plcc == nil)
    {
        plcc = [[[CustomGroupListViewCell alloc] initWithStyle:UITableViewCellStyleDefault    reuseIdentifier:CellIdentifier] autorelease];
    }


    // set up custom cell
    plcc.gourpTitle.text = @"gourpTitle";


    return plcc;

 }

 - (void) tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{

    if (dvController == nil)
    {
        GroupDetailViewController *aController = [[GroupDetailViewController alloc] initWithNibName:@"GroupDetailViewController" bundle:nil];

        self.dvController = aController;

        [aController release];
    }

    [dvController updateRowNumber:indexPath.row];
    [[self navigationController] pushViewController:dvController animated:YES];    

}

@end

GroupDetailViewController.h

#import <UIKit/UIKit.h>

@interface GroupDetailViewController : UITableViewController
{
    int rowNumber;    
}

@property(readwrite) int rowNumber;
- (void) updateRowNumber:(int) theindex;

@end

GroupDetailViewController.m

#import "GroupDetailViewController.h"

@interface GroupDetailViewController ()

@end

@implementation GroupDetailViewController

@synthesize rowNumber;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self)
    {
        // Custom initialization
    }
    return self;
}

- (void) updateRowNumber: (int) theindex
{

    rowNumber = theindex + 1;

    UILabel *label1 = [[UILabel alloc]initWithFrame:CGRectMake(50.0, 20.0, 200.0, 50.0)];

    label1.text = [NSString stringWithFormat:@"row %i was clicked ", rowNumber];
    [self.view addSubview: label1];
    [label1 release];

}

- (void)dealloc
{

    [super dealloc];
}

- (void)viewDidLoad
{

    UILabel *label1 = [[UILabel alloc]initWithFrame:CGRectMake(50.0, 20.0, 200.0, 50.0)];

    label1.text = [NSString stringWithFormat:@"row %i was clicked ", rowNumber];

    [self.view addSubview: label1];


    [super viewDidLoad];
    [label1 release];
    // Do any additional setup after loading the view from its nib.
 }

 - (void)fetchedData: (NSData *)responseData
{
    // parse out the json data
}

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Do any additional setup after loading the view from its nib.
}

- (void)viewWillAppear:(BOOL)animated
{
     [super viewWillAppear: animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear: animated];
}


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

@end

Answer 1

When initializing your view controller by calling

[[GroupDetailViewController alloc] initWithNibName:@"GroupDetailViewController" bundle:nil];

we are expecting you to provide the corresponding xib (“GroupDetailViewController”). If you don’t want to use a xib, just call

[[GroupDetailViewController alloc] init]

and implement loadView in your GroupDetailViewController class.