カスタム ナビゲーション バーとボタン アイテムです。次のコードを追加します。
UINavigationBar * bar =[[UINavigationBar alloc]initWithFrame:CGRectMake(0, 0, 320, 44)];
[self.view addSubview:bar];
//Back Button
UIButton *btnback = [UIButton buttonWithType:UIButtonTypeCustom];
[btnback setFrame:CGRectMake(0, 7, 54, 29)];
[btnback setBackgroundImage:[UIImage imageNamed:@"back.png"] forState:UIControlStateNormal];
//UILabel * btnlabel = [[UILabel alloc]initWithFrame:CGRectMake(15, 0, 40, 23)];
//btnlabel.backgroundColor = [UIColor clearColor];
//btnlabel.textColor = [UIColor whiteColor];
//btnlabel.font = [UIFont boldSystemFontOfSize:13];
//btnlabel.text = @"back";
//[btnback addSubview:btnlabel];
//[btnlabel release];
//btnlabel = nil;
[btnback addTarget:self action:@selector(BackAction:) forControlEvents:UIControlEventTouchUpInside];
[bar addSubview:btnback];
[bar release];