iPhone ツールバーを均等に配置する

ツールバーにボタンなどを単純に追加すると、左寄せになってしまう。

UIToolbar* toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 480-44, 320, 44)];
 UIBarButtonItem* prevButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRewind target:self action:@selector(clickPrev)];
    UIBarButtonItem* nextButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFastForward target:self action:@selector(clickNext)];
    UIBarButtonItem* space = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
    [toolBar setItems:[NSArray arrayWithObjects:space, prevButton, space, nextButton, space, nil]];

それを均等にする方法

間にUIBarButtonSystemItemFlexibleSpaceを入れるだけ。

UIToolbar* toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 480-44, 320, 44)];
    UIBarButtonItem* prevButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRewind target:self action:@selector(clickPrev)];
    UIBarButtonItem* nextButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFastForward target:self action:@selector(clickNext)];
    UIBarButtonItem* space = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
    [toolBar setItems:[NSArray arrayWithObjects:space, prevButton, space, nextButton, space, nil]];