Question

我有一个命令应该在特定的时间密集代码执行之前加载子视图。但是，命令运行，及时执行代码，然后显示子视图。我能解决这个问题吗？

progressViewController = [[ProgressView alloc] initWithNibName:@"ProgressView" bundle:[NSBundle mainBundle]];
[self.view addSubview:[progressViewController view]];



NSString *name=@"guy";
NSString *encodedName =[[NSString alloc] init];

int asci;

for(int i=0; i < [name length]; i++)
{
    //NSLog(@"1");
        asci = [name characterAtIndex:i];
    NSString *str = [NSString stringWithFormat:@"%d,", asci];
        encodedName =[encodedName stringByAppendingFormat: str];
}

NSString *urlString = [NSString stringWithFormat:@"someurl.com"];

NSURL *theUrl = [[NSURL alloc] initWithString:urlString];

NSString *result=[NSString stringWithContentsOfURL:theUrl];

result = [result substringFromIndex:61];
result = [result substringToIndex:[result length] - 20];

NSLog(result);


outLab.text=result;


[[progressViewController view] removeFromSuperview];

Answer 1

1）试试 [self.view setNeedsUpdating] 添加子视图后

2）尝试将时间密集分成另一个线程......

- (void) f
{
// executed in main UI thread
progressViewController = [[ProgressView alloc] initWithNibName:@"ProgressView" bundle:[NSBundle mainBundle]];
[self.view addSubview:[progressViewController view]];

  [NSThread detachNewThreadSelector:@selector(doCompute) toTarget:self
        withObject:nil];

}

- (void) doCompute
{
// in a different thread....so we need a autoreleasepool
    NSAutoreleasePool *autoreleasepool = [[NSAutoreleasePool alloc] init];
   // do your computation here...

[self performSelectorOnMainThread:@selector(taskComplete:)
                               withObject:result waitUntilDone:NO];

 [autoreleasepool release];

}

- (void) taskComplete
{
   // executed in UI thread
   [self.progressView removeFromSuperView];
}

Answer 2

您可以对视图进行子类化，然后使用viewDidLoad函数执行长时间运行的代码。

在执行代码之前未加载ipad子视图

2 个答案: