Question

我正在使用Dropbox SDK来填充数组filePaths。但是，第二次打开相应视图时，数组才会填充。当我第一次打开视图时，数组是空的。

有谁知道这是为什么？

提前致谢！

//  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

你的观察可能是错的。我猜DBRestClient在另一个线程中完成它的工作。在您离开viewWillAppear后不久，tableview获取其数据。此时DBRestClient尚未完成。

要解决此问题，只需在获取数据时重新加载tableview

将[dropboxFileView reloadData];附加到- (void)restClient:(DBRestClient*)client loadedMetadata:(DBMetadata*)metadata

在视图的第一次出现时，不会填充NSMutableArray

1 个答案: