Question

Crashes with “crashes here with EXC_BAD_ACCESS” when trying to setText within the thread.

???

thx

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController<UITextViewDelegate>
{
    UITextView *tvCommand;
}
@end

---------

-(void) Thread_Tcp
{
    [tvCommand setText:@"HELLO"];//crashes here with EXC_BAD_ACCESS
}


- (void)viewDidLoad
{
    NSThread *hThread = [NSThread alloc] initWithTarget:self selector:@selector(Thread_Tcp) object:nil];

    [hThread start];
}

Answer 1

Changes to the UI should be done from the UI thread only. This concept is similar in most of the UI programming environments / frameworks.

You can fix it by calling:

-(void) Thread_Tcp
{
    [tvCommand performSelectorOnMainThread:@selector(setText:) withObject:@"HELLO" waitUntilDone:YES];
}