Iphone UIAlertView与UIActivityIndicator有点矛盾

脱机时，我正在从联机映像下载映像以进行缓存。当我打开应用程序时，图像在UIAlertView弹出之前被完全下载。它完成得不对。我想在下载图像之前使UIAlertView弹出。下面是我的代码

- (void) operatePopupUpdating {
    myAlert = [[UIAlertView alloc] initWithTitle:@"Updating database.." message:nil delegate:self cancelButtonTitle:nil otherButtonTitles: nil];
    [myAlert show];

    UIActivityIndicatorView *indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];

    indicator.center = CGPointMake(myAlert.bounds.size.width / 2, myAlert.bounds.size.height - 50);
    [indicator startAnimating];
    [myAlert addSubview:indicator];

    [self operateUpdate];
    [self updateImage];

    [self operationCompleted];
}

在updateImage中，使用OperationUpdate和operationCompleted方法

- (void)updateImage {
NSString *snake_ico_file = @"snake_img_icn_";
NSString *filePath = [self dataFile:[snake_ico_file stringByAppendingString:@"0.jpg"]];
int max_count = [[self readData] count];
if (![[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
    for (int i = 0; i < max_count; i++) {
        NSString *path = @"http://exitosus.no.de/drngoo/image/";
        path = [path stringByAppendingFormat:@"%d",i];
        NSString *ico_path = [path stringByAppendingFormat:@"/ico"];

        //icon            
        NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        NSString *documentsDirectory = [paths objectAtIndex:0];
        NSString *filename = [snake_ico_file stringByAppendingFormat:@"%d.jpg"];
        NSString *localFilePath = [documentsDirectory stringByAppendingPathComponent:filename];
        NSData *thedata = [NSData dataWithContentsOfURL:[NSURL URLWithString:ico_path]];;
        [thedata writeToFile:localFilePath atomically:YES];
       }
}

-(void) operationCompleted
{
       [myAlert dismissWithClickedButtonIndex:0 animated:YES];

       UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Message form System" message:@"Database was updated successful" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles: nil];

       [alert show];
}

- (void)operateUpdate {

     NSString *filePath = [self dataFileSettingPath];
     int updatedVer = 0;
     int version = [self checkDatabase];
     if (version == -1) {
         updatedVer = [self createDataBase:0];
     } else {
         updatedVer = [self updateDataBase:version];
     }

     [self.settingInfo setObject:[NSString stringWithFormat:@"%d",updatedVer] forKey:@"DBVersion"];
   [self.settingInfo writeToFile:filePath atomically:YES];
}

-（void）updateImage{
NSString*snake\u ico\u文件=@“snake\u img\u icn”；
NSString*filePath=[self dataFile:[snake_ico_file stringByAppendingString:@“0.jpg]”；
int max_count=[[self readData]count]；
如果（！[[NSFileManager defaultManager]文件存在路径：文件路径]）{
对于（int i=0；i

---

如何修复它们并正确工作？

只有在图像下载完成后，alertView才会显示。解决此问题的一个解决方案是

创建另一个类ImageDownLoad.h

in.h

英寸

@synthesize delegate;
@synthesize path;

创建一个方法，即

-(void)startDownloadImageWithUrl:(NSURL*)imageUrl withLocalFilePath:(NSSTring*)filePath{
       path = filePath;
       receiveData = [NSMutableData data];
       NSURLRequest *request = [[NSURLRequest alloc]initWithURL:imageUrl];
       NSURLConnection *connection = [[NSURLConnection alloc]initWithRequest:request];
 }

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
        [receiveData appendData:data];
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection{
        [(id)delegate performSelector:@selector(SaveData:inFilePath:) withObject:receiveData withObject:path];
}

这将创建连接并开始在单独的类中下载图像。然后在mai ViewController中添加如下代码

  - (void)updateImage {
          NSString *snake_ico_file = @"snake_img_icn_";
          NSString *filePath = [self dataFile:[snake_ico_file stringByAppendingString:@"0.jpg"]];
          int max_count = [[self readData] count];
          if (![[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
                 for (int i = 0; i < max_count; i++) {
                 NSString *path = @"http://exitosus.no.de/drngoo/image/";
                 path = [path stringByAppendingFormat:@"%d",i];
                 NSString *ico_path = [path stringByAppendingFormat:@"/ico"];

                      //icon            
                 NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
                 NSString *documentsDirectory = [paths objectAtIndex:0];
                 NSString *filename = [snake_ico_file stringByAppendingFormat:@"%d.jpg"];
                 NSString *localFilePath = [documentsDirectory stringByAppendingPathComponent:filename];

                 ImageDownLoad *imageDown = [[ImageDownLoad alloc]init];
                 imageDown.delegate = self;
                 [imageDown startDownloadImageWithUrl:[NSURL URLWithString:ico_path] withLocalFilePath:localFilePath];

            }
   }

---

您的UI不会因此而延迟：）

只有在图像下载完成后，alertView才会显示。解决此问题的一个解决方案是

创建另一个类ImageDownLoad.h

in.h

英寸

@synthesize delegate;
@synthesize path;

创建一个方法，即

-(void)startDownloadImageWithUrl:(NSURL*)imageUrl withLocalFilePath:(NSSTring*)filePath{
       path = filePath;
       receiveData = [NSMutableData data];
       NSURLRequest *request = [[NSURLRequest alloc]initWithURL:imageUrl];
       NSURLConnection *connection = [[NSURLConnection alloc]initWithRequest:request];
 }

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
        [receiveData appendData:data];
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection{
        [(id)delegate performSelector:@selector(SaveData:inFilePath:) withObject:receiveData withObject:path];
}

这将创建连接并开始在单独的类中下载图像。然后在mai ViewController中添加如下代码

  - (void)updateImage {
          NSString *snake_ico_file = @"snake_img_icn_";
          NSString *filePath = [self dataFile:[snake_ico_file stringByAppendingString:@"0.jpg"]];
          int max_count = [[self readData] count];
          if (![[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
                 for (int i = 0; i < max_count; i++) {
                 NSString *path = @"http://exitosus.no.de/drngoo/image/";
                 path = [path stringByAppendingFormat:@"%d",i];
                 NSString *ico_path = [path stringByAppendingFormat:@"/ico"];

                      //icon            
                 NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
                 NSString *documentsDirectory = [paths objectAtIndex:0];
                 NSString *filename = [snake_ico_file stringByAppendingFormat:@"%d.jpg"];
                 NSString *localFilePath = [documentsDirectory stringByAppendingPathComponent:filename];

                 ImageDownLoad *imageDown = [[ImageDownLoad alloc]init];
                 imageDown.delegate = self;
                 [imageDown startDownloadImageWithUrl:[NSURL URLWithString:ico_path] withLocalFilePath:localFilePath];

            }
   }

---

您的UI不会因为这样做而延迟：）

请编辑您的标题或问题的内容：UIAlertView与UIActivityIndicator有点矛盾。它检查数据库是否更新。我在上面编辑了我的代码。请编辑您的标题或问题的内容：UIAlertView与UIActivityIndicator有点矛盾。它检查数据库是否有updating。我在上面编辑了我的代码。我用这个建议实现，然后我得到SaveData]：未识别的选择器发送到实例。这个方法可以在弹出消息之前等待下载完成吗？@WaiToNZa我编辑过，这应该像[（id）delegate performSelector:@selector（SaveData:inFilePath:）with object:receiveData with object:path]；非常感谢您解决此问题。：我使用此建议实施，然后我将获得SaveData]：无法识别的选择器发送到实例。此方法可以在弹出消息之前等待下载完成吗？@WaiToNZa I edited，这应该类似于[（id）delegate performSelector:@selector（SaveData:inFilePath:）withObject:receiveData withObject:path]；非常感谢您解决此问题。：D