ビューの最初の外観にNSMutableArrayが設定されない

Question

私はDropbox SDKを使用して配列filePathsを埋めています。 しかし、配列は、2回目に対応するビューを開くときにのみ塗りつぶされます。初めてビューを開くと、配列は空です。

これはなぜですか？

ありがとうございます！

// DropboxFileViewController.m 

#import "DropboxFileViewController.h" 
#import "DropboxViewController.h" 
#import "DropboxSDK.h" 
#import <stdlib.h> 


@interface DropboxFileViewController() <DBRestClientDelegate> 


@property (nonatomic, readonly) DBRestClient* restClient; 

@end 


@implementation DropboxFileViewController 
@synthesize dropboxFileView; 
@synthesize filePaths; 



- (void)restClient:(DBRestClient*)client loadedMetadata:(DBMetadata*)metadata { 

    //NSArray* validExtensions = [NSArray arrayWithObjects:@"pdf", @"docx", @"doc", nil]; 
    NSMutableArray* newDropboxFilePaths = [NSMutableArray new]; 
    for (DBMetadata* child in metadata.contents) { 
     //NSString* extension = [[child.path pathExtension] lowercaseString]; 
     //if (!child.isDirectory && [validExtensions indexOfObject:extension] != NSNotFound) { 
      [newDropboxFilePaths addObject:child.path]; 
     //} 
    } 

    [filePaths release]; 
    filePaths = newDropboxFilePaths; 
} 



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

#pragma mark - 
#pragma mark Initialization 

/* 
- (id)initWithStyle:(UITableViewStyle)style { 
    // Override initWithStyle: if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad. 
    self = [super initWithStyle:style]; 
    if (self) { 
     // Custom initialization. 
    } 
    return self; 
} 
*/ 


#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]; 
    [self.restClient loadMetadata:@"/"]; 


} 

- (DBRestClient*)restClient { 
    if (restClient == nil) { 
     restClient = [[DBRestClient alloc] initWithSession:[DBSession sharedSession]]; 
     restClient.delegate = self; 
    } 
    return restClient; 
} 


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

} 

/* 
- (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 [filePaths count]; 
    //NSLog(@"deze shit wordt geinvoked vriend"); 

} 


// 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... 


    //NSDictionary *dictionary = [listOfItems objectAtIndex:indexPath.section]; 

    NSUInteger row = [indexPath row]; 
    cell.textLabel.text = [filePaths objectAtIndex:row]; 
    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

あなたの所見が間違っている可能性があります。 DBRestClientは別のスレッドでその作業を行うと思います。そしてviewWillAppearを離した直後に、tableviewはそのデータを取得します。この時点でDBRestClientは完了していません。 - (void)restClient:(DBRestClient*)client loadedMetadata:(DBMetadata*)metadata