I started a thread in background in a UIview, what happens to the thread after I left the view?

Question

I started a thread in a UIview as a background thread which transfer data for the view. However, crash happens in such situation: When I left the view at the very time that the thread is trying to transfer data.

I didn't get quite clear with the relationship between the UIview object and thread. I guess it crashes because the thread was trying to visit UIview members or methods, which were not existed any more. So, I wonder what happened to the thread if the UIView which detach it has been left.

This is my detaching code:

- (void)reloadData {
    isLoaded = NO; //UIView member.
    [NSThread detachNewThreadSelector:@selector(getThreadInAnotherThread) toTarget:self withObject:nil];
}


- (void)getThreadInAnotherThread {
             //Loading code
             isLoaded = YES;
    [self performSelectorOnMainThread:@selector(reloadTable) withObject:nil waitUntilDone:YES]; 
}

And I didn't do anything in viewDidDisappear.

Answer 1

There is no relationship between the view and the thread unless you put one there yourself.

Answer 2

As the documentation for detachNewThreadSelector:toTarget:withObject states:

The objects aTarget and anArgument are retained during the execution of the detached thread, then released.

And the same for performSelectorOnMainThread:withObject:waitUntilDone:

This method retains the receiver and the arg parameter until after the selector is performed.

If its still not clear what is happening here consult the cocoa memory management guide.