[IPhone]UIBarButtonItem에 Custom Button으로 Image로 바꾸기

UIButton *button = [[UIButton buttonWithType:UIButtonTypeCustom] retain];

button.frame = CGRectMake(0.0f, 0.0f, 49.0f, 30.0f);

[button setBackgroundImage:[UIImage imageNamed:@"btn_before.png"] forState:UIControlStateHighlighted];

[button setBackgroundImage:[UIImage imageNamed:@"btn_before_on.png"] forState:UIControlStateNormal];        

[button addTarget:self action:@selector(pressBack:) forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *temporaryBarButtonItem=[[UIBarButtonItem alloc] initWithCustomView:button];

[temporaryBarButtonItem setStyle:UIBarButtonItemStyleBordered];

self.navigationItem.leftBarButtonItem =temporaryBarButtonItem;

[button release];

[temporaryBarButtonItem release];