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];