UIBarbuttonItem不在工具欄的右側？

Question

我在我的視圖控制器中的代碼在視圖中沒有這樣的負載..但UIBarButtonItem不在工具欄的右側。它在左側。任何幫助？如何給工具欄的標題也？

UIToolbar *toolbar = [UIToolbar new]; 
toolbar.barStyle = UIBarStyleBlackTranslucent; 

// create a bordered style button with custom title 
UIBarButtonItem *playItem = [[[UIBarButtonItem alloc] initWithTitle:@"Play" 
      style:UIBarButtonItemStyleBordered 
      target:self 
      action:@selector(flipToSchedules:)] autorelease]; 
self.navigationItem.rightBarButtonItem = playItem; 
NSArray *items = [NSArray arrayWithObjects: playItem, nil]; 
toolbar.items = items; 

// size up the toolbar and set its frame 
// please not that it will work only for views without Navigation toolbars. 
[toolbar sizeToFit]; 
CGFloat toolbarHeight = [toolbar frame].size.height; 
CGRect mainViewBounds = self.view.bounds; 

[toolbar setFrame:CGRectMake(0, 20, 
      CGRectGetWidth(mainViewBounds), toolbarHeight)]; 
[self.view addSubview:toolbar]; 

Answer 1

分配playItem作爲的self.navigationItemrightBarButtonItem沒有意義，因爲這將設置按鈕，在頂部導航欄的按鈕，你想要把它放在工具欄（在底部）

爲了解決這個問題，你必須具有靈活的寬度創建另一個按鈕，並補充說，作爲工具欄的第一個項目：

UIBarButtonItem *flexible = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil]; 
toolbar.items = [NSArray arrayWithObjects:flexible, playItem, nil]; 
[flexible release];