右のナビゲーションボタンにカスタムUIViewを使用するだけで、2つのボタンを切り替えることができます。
右のナビゲーションボタンアイテムとして表示されるカスタムUIViewを作成する簡単なアプローチを使用できます。このUIViewには、切り替えたい2つのUIButtonが含まれている必要があります。UIButtonはUIViewでもあるため、通常のUIビューを反転できるのと同じトランジションを使用して反転でき、もちろんタップすることもできます。動作するサンプルコードは次のとおりです。
注：便利な関数を使用して、UIViewControllerのカスタムカテゴリとしてボタンを作成します（注：これと同じコードを追加して、UIViewのカスタムカテゴリを作成することもできます。同じ行をコピーして、UIViewControllerをUIViewに置き換えてください）-必要に応じて以下のコードを含めてカスタムカテゴリを作成するだけでも使用できます。または、通常どおりにUIButtonを作成することもできます。
// create custom category for UIViewController to allow common button creation routine, add to .m or .mm file or add to a .h file and #import that .h file
@interface UIViewController (ButtonAndSelector)
- (UIButton *)createUIButtonWithImage:(UIImage *)image forState:(UIControlState)state withSelector:(SEL)selector usingFrame:(CGRect)buttonImageFrame;
@end
@implementation UIViewController (ButtonAndSelector)
- (UIButton *)createUIButtonWithImage:(UIImage *)buttonImage forState:(UIControlState)state withSelector:(SEL)selector usingFrame:(CGRect)buttonImageFrame
{
UIButton *button = [[UIButton alloc] initWithFrame:buttonImageFrame];
[button setBackgroundImage:buttonImage forState:state];
[button addTarget:self action:selector forControlEvents:UIControlEventTouchUpInside];
[button setShowsTouchWhenHighlighted:YES];
return button;
}
@end
// add this to your .h file:
@property (strong, nonatomic) UIView *coverListView;
@property (strong, nonatomic) UIButton *listButton;
@property (strong, nonatomic) UIButton *coverButton;
- (void)animateCoverListButtonFlip;
// add this to your .m or .mm file to synthesize the variables:
@synthesize coverListView;
@synthesize listButton;
@synthesize coverButton;
// add this to your .m or .mm file in the viewDidLoad:
// setup right button bar (flips between list icon and coverart image)
self.coverListView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 32, 30)];
self.coverListView.backgroundColor = [UIColor clearColor];
self.coverListView.opaque = NO;
self.listButton = [self createUIButtonWithImage:[UIImage imageNamed:@"navbar_icon_tracklisting"] forState:UIControlStateNormal withSelector:@selector(showHideQueue) usingFrame:CGRectMake(0, 0, 32, 30)];
self.listButton.backgroundColor = [UIColor clearColor];
self.listButton.showsTouchWhenHighlighted = NO;
self.coverButton = [self createUIButtonWithImage:[UIImage imageNamed:@"default_coverart_small"] forState:UIControlStateNormal withSelector:@selector(showHideQueue) usingFrame:CGRectMake(0, 0, 32, 30)];
[self.coverListView addSubview:self.coverButton]; // show coverButton by default
self.coverButton.showsTouchWhenHighlighted = NO;
UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:self.coverListView];
[self.navigationItem setRightBarButtonItem:barButtonItem];
// add this to viewDidAppear if you want to flip the button when the screen appears like the build in iPod app does
[self animateCoverListButtonFlip];
// add this routine to flip the right navigation bar custom view / buttons
- (void)animateCoverListButtonFlip
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.75];
[UIView setAnimationTransition:([self.listButton superview] ? UIViewAnimationTransitionFlipFromLeft : UIViewAnimationTransitionFlipFromRight) forView:self.coverListView cache:YES];
if ([self.listButton superview]) {
[self.listButton removeFromSuperview];
[self.coverListView addSubview:self.coverButton];
} else {
[self.coverButton removeFromSuperview];
[self.coverListView addSubview:self.listButton];
}
[UIView commitAnimations];
}
// when the playing album cover changes, remember to update the coverButton:
UIImage *artworkImage; // set this to the current playing album image
[self.coverButton setImage:artworkImage forState:UIControlStateNormal];
// don't forget to call the animateCoverListButtonFlip in the button click handler (shown above as showHideQueue) that shows and hides the cover/queue(list of album tracks0 - something like this:
- (void)showHideQueue
{
[self animateCoverListButtonFlip];
/* replace the code below that is commented out here with your own code that transitions between your cover view and your list view of album tracks, this code shows my transition and references views that are not part of this example/answer, but you don't need those - you'll have your own cover view (musicPlayerView) and list view (musicQueueView) to flip between.
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.75];
[UIView setAnimationTransition:([musicQueueView superview] ? UIViewAnimationTransitionFlipFromLeft : UIViewAnimationTransitionFlipFromRight) forView:self.contentView cache:YES];
if ([musicQueueView superview]) { // if music queue is displayed
[musicQueueView removeFromSuperview];
[self.contentView addSubview:musicPlayerView];
} else {
[musicPlayerView removeFromSuperview];
[self.contentView addSubview:musicQueueView];
[[musicQueueView queueTableView] reloadData];
}
[UIView commitAnimations];*/
}