I have list of file with some name of friends. I am trying to understand UITableViewNavigation . I load the list from a file but when I select a cell the Data Array at that point seems empty and I can not work out why.
At this method I get this error - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
FriendsNameViewController *newView =[[FriendsNameViewController alloc] initWithNibName:@"FriendsNameViewController" bundle:nil];
[self.navigationController pushViewController:newView animated:YES];
//Crashes here
NSString *temp = [dataArray objectAtIndex:indexPath.row];
NSLog(@"%@",temp);
[[newView labelx] setText:[NSString stringWithFormat: @"%@" ,temp]];
}
2011-10-03 14:43:08.411 navman2[69691:b303] * Terminating app due to uncaught exception 'NSRangeException', reason: '* -[NSMutableArray objectAtIndex:]: index 2 beyond bounds for empty array'
Interface
#import <UIKit/UIKit.h>
@interface TableViewController : UITableViewController
{
NSArray *dataArray;
}
@property(retain,nonatomic) NSArray *dataArray;
@end
and then implementaion here
#import "TableViewController.h"
#import "FriendsNameViewController.h"
@implementation TableViewController
@synthesize dataArray;
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, ima开发者_如何学Goges, etc that aren't in use.
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"myfriendsList" ofType:@"txt"];
NSStringEncoding encoding;
NSError* error;
NSString* fh = [NSString stringWithContentsOfFile:filePath usedEncoding:&encoding error:&error];
dataArray = [NSArray alloc];
dataArray = [fh componentsSeparatedByString:@"\n"];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (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];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
#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 [dataArray count];
}
- (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...
cell.textLabel.text = [dataArray objectAtIndex:indexPath.row];
return cell;
}
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
FriendsNameViewController *newView =[[FriendsNameViewController alloc] initWithNibName:@"FriendsNameViewController" bundle:nil];
[self.navigationController pushViewController:newView animated:YES];
//Crashes here
NSString *temp = [dataArray objectAtIndex:indexPath.row];
NSLog(@"%@",temp);
[[newView labelx] setText:[NSString stringWithFormat: @"%@" ,temp]];
}
@end
If you have verified that the array is correct prior to selecting, then the first thing I would try is to rearrange your code a little bit:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
FriendsNameViewController *newView =[[FriendsNameViewController alloc] initWithNibName:@"FriendsNameViewController" bundle:nil];
NSString *temp = [dataArray objectAtIndex:indexPath.row];
NSLog(@"%@",temp);
[[newView labelx] setText:[NSString stringWithFormat: @"%@" ,temp]];
[self.navigationController pushViewController:newView animated:YES];
}
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