iPhone NavigationBar和UIToolbar基础

navigation bar 分为三个部分,左按钮,右按钮和中间的View.

在Controller中可以通过以三个方式来引用:

 

• self . navigationItem. titleView
• self . navigationItem. leftBarButtonItem
• self . navigationItem. rightBarButtonItem

左右按钮可以使用UIBarButtonItem来构造. 他默认有很多种按钮可攻选择:

 typedef  enum  {
     UIBarButtonSystemItemDone,
     UIBarButtonSystemItemCancel,
     UIBarButtonSystemItemEdit,
     UIBarButtonSystemItemSave,
     UIBarButtonSystemItemAdd,
     UIBarButtonSystemItemFlexibleSpace,
     UIBarButtonSystemItemFixedSpace,
     UIBarButtonSystemItemCompose,
     UIBarButtonSystemItemReply,
     UIBarButtonSystemItemAction,
     UIBarButtonSystemItemOrganize,
     UIBarButtonSystemItemBookmarks,
     UIBarButtonSystemItemSearch,
     UIBarButtonSystemItemRefresh,
     UIBarButtonSystemItemStop,
     UIBarButtonSystemItemCamera,
     UIBarButtonSystemItemTrash,
     UIBarButtonSystemItemPlay,
     UIBarButtonSystemItemPause,
     UIBarButtonSystemItemRewind,
     UIBarButtonSystemItemFastForward,
     UIBarButtonSystemItemUndo,      // available in iPhone 3.0
     UIBarButtonSystemItemRedo,      // available in iPhone 3.0
 } UIBarButtonSystemItem;

 

通过构造初始化可以设置这些按钮的种类:

 [[[UIBarButtonItem alloc]
              initWithBarButtonSystemItem:UIBarButtonSystemItemPlay
              target:nil action:NULL] autorelease];

 

除此之外,UIBarButtonItem还有几种外观风格:

 typedef  enum  {
     UIBarButtonItemStylePlain,    // shows glow when pressed
     UIBarButtonItemStyleBordered,
     UIBarButtonItemStyleDone,
 } UIBarButtonItemStyle;

 

当然按钮有风格之分, navigation bar 也有几种可选风格:

 typedef  enum  {
     UIBarStyleDefault          = 0 ,
     UIBarStyleBlack            = 1 ,

     UIBarStyleBlackOpaque      = 1 ,  // Deprecated. Use UIBarStyleBlack
     UIBarStyleBlackTranslucent = 2 , // Deprecated. Use UIBarStyleBlack and set the translucent property to YES
 } UIBarStyle;

 

通过:navigationController . navigationBar . barStyle  =  UIBarStyleBlackTranslucent这样的语句就可以设置了.

这个UIBarStyle的风格还适用于UIToolbar. 并且UIToolBar中也是可以放置UIBarButtonItem的.

 NSMutableArray *buttons = [[NSMutableArray alloc] initWithCapacity: 4 ];

     UIBarButtonItem *flexibleSpaceItem;
     flexibleSpaceItem = [[[UIBarButtonItem alloc]
                           initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
                           target:nil action:NULL] autorelease];
     [buttons addObject:flexibleSpaceItem];
     [flexibleSpaceItem release];

     UIBarButtonItem *item;
     item = [[UIBarButtonItem alloc]
             initWithImage:[UIImage imageNamed:@"down.png" ]
             style:UIBarButtonItemStylePlain
             target:self
             action:@selector (decrement:)];
     [buttons addObject:item];
     [item release];

     item = [[UIBarButtonItem alloc]
             initWithImage:[UIImage imageNamed:@"up.png" ]
             style:UIBarButtonItemStylePlain target:self
             action:@selector (increment:)];
     [buttons addObject:item];
     [item release];

     item = [[[UIBarButtonItem alloc]
              initWithBarButtonSystemItem:UIBarButtonSystemItemPlay
              target:nil action:NULL] autorelease];
     [buttons addObject:item];
     [item release];


     flexibleSpaceItem = [[[UIBarButtonItem alloc]
                           initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
                           target:nil action:NULL] autorelease];

     [buttons addObject:flexibleSpaceItem];
     [flexibleSpaceItem release];


     UIToolbar *toolbar = [[UIToolbar alloc] init];
     toolbar.barStyle = UIBarStyleBlackOpaque;
     [toolbar setItems:buttons animated:YES];
     [toolbar sizeToFit];