UIActivityIndicatorViewを別スレッドで実行する

Indicator.h

//
//  IndicatorClass.h

#import <Foundation/Foundation.h>

@interface IndicatorClass : NSObject
{
    UIView *_loadingView;    
    UIActivityIndicatorView *_indicator; 
    UILabel *_label;
}


- (void)accessStart :(UIView *) _uiview WithWord:(NSString*) word;
- (void)accessEnd;


@property (nonatomic, retain) UIView *loadingView;
@property (nonatomic, retain) UIActivityIndicatorView *indicator;
@property (nonatomic, retain) UILabel *label;

@end

Indicator.m

//
//  IndicatorClass.m

#import "IndicatorClass.h"

@implementation IndicatorClass
@synthesize loadingView = _loadingView;
@synthesize indicator = _indicator;
@synthesize label = _label;

- (void)accessStart :(UIView *) _uiview WithWord:(NSString*) word
{

    //インジケータON（画面中央）
    _loadingView = [[UIView alloc] initWithFrame:[_uiview bounds]];
    [_loadingView setBackgroundColor:[UIColor blackColor]];
    [_loadingView setAlpha:0.5];
    _indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
    [_loadingView addSubview:_indicator];
    [_indicator setFrame:CGRectMake ((320/2)-20, (480/2)-60, 40, 40)];
    [_indicator startAnimating];    



    _label = [[UILabel alloc] initWithFrame:CGRectMake((320/2)-50, (480/2)-10,100,30)];
    _label.backgroundColor = [UIColor clearColor];
    _label.text = word;
    [_loadingView addSubview:_label];
    [_uiview addSubview:_loadingView];    

}

- (void)accessEnd
{
    // 画面中央の処理中インジケータ表示OFF
    [_indicator stopAnimating];
    [_loadingView removeFromSuperview];
    [_label removeFromSuperview];
}

- (void)dealloc
{
    _loadingView = nil;
    _indicator = nil;
    _label = nil;
    [super dealloc];
}


@end

実行ファイル

- (void)main
{
    [_indicator accessStart:self.view WithWord:@"更新中..."];
    [self performSelectorInBackground:@selector(insertViewData) withObject:nil];
}

- (void)insertViewData
{
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

//重たい処理

    [_indicator accessEnd];
    [pool release];

}