ButtonBar, FlexibleHeader, HeaderStackView, and NavigationBar are all implementation details of AppBar. While these components can be used on their own, in practice we expect most typical usage to rely on AppBar. FlexibleHeader is a bit blurry in that there is often value in relying on it solely, but because it is not a true concept in the spec and its behavioral demos largely overlap with AppBar's, it is now a dragons demo. Pivotal story: https://www.pivotaltracker.com/story/show/156982162
Button Bar
The Button Bar is a view that represents a list of UIBarButtonItems as horizontally aligned buttons.
Design & API documentation
Related components
Table of contents
Overview
A Button Bar is similar in concept to a UIToolbar, but Button Bars are *not
Button Bar supports a subset of UIBarButtonItem's properties. Learn more by reading the section on UIBarButtonItem properties.
Installation
Installation with CocoaPods
Add the following to your Podfile:
pod 'MaterialComponents/ButtonBar'
Then, run the following command:
pod install
Importing
To import the component:
Swift
import MaterialComponents.MaterialButtonBar
Objective-C
#import "MaterialButtonBar.h"
Usage
Typical use
Swift
let buttonBar = MDCButtonBar()
let actionItem = UIBarButtonItem(
title: "<# title #>",
style: .done, // ignored
target: self,
action: "<# selector #>"
)
buttonBar.items = [actionItem]
let size = buttonBar.sizeThatFits(self.view.bounds.size)
buttonBar.frame = CGRect(x: <# x #>, y: <# y #>, width: size.width, height: size.height)
self.view.addSubview(buttonBar)
Objective-C
MDCButtonBar *buttonBar = [[MDCButtonBar alloc] init];
UIBarButtonItem *actionItem =
[[UIBarButtonItem alloc] initWithTitle:@"<# title #>"
style:UIBarButtonItemStyleDone // ignored
target:self
action:@selector(<# selector #>)];
buttonBar.items = @[ actionItem ];
CGSize size = [buttonBar sizeThatFits:self.view.bounds.size];
CGPoint origin = CGPointZero;
buttonBar.frame = CGRectMake(origin.x, origin.y, size.width, size.height);
[self.view addSubview:buttonBar];
Supported UIBarButtonItem properties
The following properties are taken into consideration when items is set and the corresponding
buttons are created.
Changes made to properties marked (observed) will be reflected in the corresponding buttons.
title(observed)image(observed)enabled(observed)widthtargetactiontitleTextAttributesForState:
TODO(featherless): File bugs to observe the rest of the properties.
Note: in order to make Button Bar reflect changes to not-observed properties you must clear the
MDCButtonBar instance's items property and reset it, like so:
Swift
actionItem.target = <some other target>
let items = buttonBar.items
buttonBar.items = nil
buttonBar.items = items
Objective-C
actionItem.target = <some other target>;
NSArray *items = buttonBar.items;
buttonBar.items = nil;
buttonBar.items = items;
Extensions
Color Theming
You can theme a button bar with your app's color scheme using the ColorThemer extension.
You must first add the Color Themer extension to your project:
pod 'MaterialComponents/ButtonBar+Extensions/ColorThemer'
Swift
// Step 1: Import the ColorThemer extension
import MaterialComponents.MaterialButtonBar_ColorThemer
// Step 2: Create or get a color scheme
let colorScheme = MDCSemanticColorScheme()
// Step 3: Apply the color scheme to your component
MDCButtonBarColorThemer.applySemanticColorScheme(colorScheme, to:buttonBar)
Objective-C
// Step 1: Import the ColorThemer extension
#import "MaterialButtonBar+ColorThemer.h"
// Step 2: Create or get a color scheme
id<MDCColorScheming> colorScheme = [[MDCSemanticColorScheme alloc] init];
// Step 3: Apply the color scheme to your component
[MDCButtonBarColorThemer applySemanticColorScheme:colorScheme
toButtonBar:buttonBar];
Typography Theming
You can theme a button bar with your app's typography scheme using the TypographyThemer extension.
You must first add the Typography Themer extension to your project:
pod 'MaterialComponents/ButtonBar+Extensions/TypographyThemer'
Swift
// Step 1: Import the TypographyThemer extension
import MaterialComponents.MaterialButtonBar_TypographyThemer
// Step 2: Create or get a typography scheme
let typographyScheme = MDCTypographyScheme()
// Step 3: Apply the typography scheme to your component
MDCButtonBarTypographyThemer.applyTypographyScheme(typographyScheme, to: buttonBar)
Objective-C
// Step 1: Import the TypographyThemer extension
#import "MaterialButtonBar+TypographyThemer.h"
// Step 2: Create or get a typography scheme
id<MDCTypographyScheming> typographyScheme = [[MDCTypographyScheme alloc] init];
// Step 3: Apply the typography scheme to your component
[MDCButtonBarTypographyThemer applyTypographyScheme:colorScheme
toButtonBar:buttonBar];
