我有tableView，其中包含ViewControllers列表。此表格底部是通过iAd发布的广告。当您访问这些VC中的任何一个时，然后点击navigationController上的“返回”，iAd就像您离开时一样 - 除了其中一个视图控制器。在访问此广告之后，广告就像你离开它一瞬间，然后变成白色大约十秒钟，然后最后 - 有时 - 重新加载另一个广告。我不确定推送这个特定的VC会导致广告在返回时失败。我想的可能是后台线程上与UI相关的东西，或与线程相关的东西，但我根本不确定。这是VC的代码，在navControl上“返回”后，导致tableView的广告变为白色（此VC，另一个tableView，拥有自己的iAd和iAd委托方法）：
#import "RosterTableTableViewController.h"
#import "RosterListing.h"
#import "RosterListingCellTableViewCell.h"
#import "PlayerDetailViewController.h"
#import <iAd/iAd.h>
#import "RosterListingModel.h"
@interface RosterTableTableViewController () <ADBannerViewDelegate>
{
RosterListingModel *_homeModel;
BOOL _bannerIsVisible;
ADBannerView *_adBanner;
}
@property (nonatomic, strong) NSMutableArray *rosters;
@property NSCache *imageCache;
@property UIActivityIndicatorView *spinner;
@end
@implementation RosterTableTableViewController
-(void)itemsDownloaded:(NSArray *)items
{
// This delegate method will get called when the items are finished downloading
// Set the downloaded items to the array
_rosters = [items copy];
[_spinner stopAnimating];
// Reload the table view
[self.tableView reloadData];
}
- (instancetype)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Create new HomeModel object and assign it to _homeModel variable
_homeModel = [[RosterListingModel alloc] init];
self.navigationItem.title = @"Roster";
self.imageCache = [[NSCache alloc] init];
self.rosters = [[NSMutableArray alloc] init];
// Set this view controller object as the delegate for the home model object
_homeModel.delegate = self;
// Call the download items method of the home model object
[_homeModel downloadItems];
}
return self;
}
- (void)bannerView:(ADBannerView *)banner didFailToReceiveAdWithError:(NSError *)error
{
NSLog(@"Failed to retrieve ad");
if (_bannerIsVisible)
{
[UIView beginAnimations:@"animateAdBannerOff" context:NULL];
// Assumes the banner view is placed at the bottom of the screen.
banner.frame = CGRectOffset(banner.frame, 0, banner.frame.size.height);
[UIView commitAnimations];
_bannerIsVisible = NO;
}
}
- (void) viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear: animated];
[UIView setAnimationsEnabled:YES];
}
- (void) tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
UIStoryboard *sb = [UIStoryboard storyboardWithName:@"RosterDetail" bundle:nil];
PlayerDetailViewController *vc = [sb instantiateViewControllerWithIdentifier:@"PlayerDetailViewController"];
// Give the PlayerViewController its key
RosterListing *rl = [self.rosters objectAtIndex:indexPath.row];
vc.playerNumberKey = rl.playerNumber;
vc.playerNameKey = rl.playerName;
vc.playerImage = rl.image;
// Present vc
vc.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
//[self.navigationController pushViewController:vc animated:YES];
[UIView beginAnimations:@"animation" context:nil];
[self.navigationController pushViewController: vc animated:NO];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.navigationController.view cache:NO];
[UIView setAnimationDuration:0.75];
[UIView commitAnimations];
}
- (void)viewDidLoad {
[super viewDidLoad];
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc]
initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
CGRect screenRect = [[UIScreen mainScreen] bounds];
CGFloat screenWidth = screenRect.size.width;
CGFloat screenHeight = screenRect.size.height;
spinner.center = CGPointMake(screenWidth/2.0, screenHeight/5.0);
spinner.hidesWhenStopped = YES;
spinner.color = [UIColor blackColor];
[self.view addSubview:spinner];
[spinner startAnimating];
_spinner = spinner;
// Load the Cell NIB file
UINib *nib = [UINib nibWithNibName:@"RosterListingCellTableViewCell" bundle:nil];
// Register this NIB, which contains the cell
[self.tableView registerNib:nib forCellReuseIdentifier:@"RosterCell"];
// Background
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"ticketBackground"]];
imageView.contentMode = UIViewContentModeScaleAspectFill;
self.tableView.backgroundView = imageView;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (CGFloat) tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return 74;
}
#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 self.rosters.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
// Get a new or recycled cell
RosterListingCellTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"RosterCell" forIndexPath:indexPath];
RosterListing *thisRosterListing = [self.rosters objectAtIndex:indexPath.row];
cell.playerNumberLabel.text = [NSString stringWithFormat:@"#%@",thisRosterListing.playerNumber];
cell.playerNameLabel.text = thisRosterListing.playerName;
cell.imageView.image = [UIImage imageNamed:@"omaha"];
cell.imageView.contentMode = UIViewContentModeScaleAspectFill;
cell.imageView.clipsToBounds = YES;
UIImage *playerImage = [self.imageCache objectForKey:thisRosterListing.playerImageURL];
cell.imageView.image = playerImage;
if (playerImage == nil) {
NSURLSessionConfiguration *sessionConfig =
[NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfig delegate:self delegateQueue:nil];
thisRosterListing.playerImageURL = [thisRosterListing.playerImageURL stringByReplacingOccurrencesOfString:@"small" withString:@"medium"];
NSURLSessionDataTask *imageData = [session dataTaskWithURL:[NSURL URLWithString: thisRosterListing.playerImageURL]
completionHandler:^(NSData *data,
NSURLResponse *response,
NSError *error) {
// handle NSData
UIImage *image = [UIImage imageWithData:data];
thisRosterListing.image = image;
[self.imageCache setObject:image forKey:thisRosterListing.playerImageURL];
dispatch_async(dispatch_get_main_queue(), ^{
cell.imageView.image = image;
[self.tableView reloadData];
});
}];
[imageData resume];
}
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 20, 20)];
imageView.image = [UIImage imageNamed:@"indicator"];
cell.accessoryView = imageView;
cell.backgroundColor = [UIColor clearColor];
// set selection color
UIView *myBackView = [[UIView alloc] initWithFrame:cell.frame];
myBackView.backgroundColor = [UIColor clearColor];
cell.selectedBackgroundView = myBackView;
return cell;
}
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 65)];
view.backgroundColor = [UIColor clearColor];
if (_adBanner == nil)
{
_adBanner = [[ADBannerView alloc] initWithFrame:CGRectMake(0, 0, 320, 50)];
}
_adBanner.delegate = self;
_adBanner.backgroundColor = [UIColor clearColor];
[view addSubview:_adBanner];
return view;
}
- (CGFloat) tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
return 65;
}
@end