Cards

Cards contain content and actions about a single subject. They can be used standalone, or as part of a list. Cards are meant to be interactive, and aren't meant to be be used solely for style purposes.

Design & API documentation

Table of contents

• Overview
  • Cards Classes
• Installation
  • Installation with CocoaPods
  • Importing
• Usage
  • Typical use: as a view
  • Typical use: in a collection view
• Extensions
  • Color Theming

Overview

Cards provides two different versions, MDCCard inheriting from UIControl and MDCCardCollectionCell inheriting from UICollectionViewCell.

A card's state determines its visual styling.

When treated as a UIControl (MDCCard), it has a default styling (UIControlStateNormal), and a highlighted styling (UIControlStateHighlighted) when interacted with.

When treated as a UICollectionViewCell (MDCCardCollectionCell), it has a default styling (MDCCardCellStateNormal), a highlighted styling (MDCCardCellStateHighlighted), and lastly a selected styling (MDCCardCellStateSelected).

Customization to the card is exposed via its API either in MDCCard or MDCCardCollectionCell. Currently the card consists of these customizations:

• The border width for a specific state
• The border color for a specific state
• The shadow elevation for a specific state
• The shadow color for a specific state
• The corner radius for the card

(MDCCardCollectionCell customization only):

• Changing the image that appears in the Selected state.
• Changing the image tint color that appears in the Selected state.

An MDCCard can be added and used as you would add any UIView or UIControl, if manually in code, or through Interface Builder.

An MDCCardCollectionCell can be added, used, and reused as a UICollectionViewCell, if manually in code, or through Interface Builder.

MDCCardThemer exposes apis to theme MDCCard and MDCCardCollectionCell instances as either a default or outlined variant. An outlined variant behaves identically to a default styled card, but differs in its coloring and in that it has a stroked border. Use ‘applyScheme:toCard:’ to style an instance with default values and ‘applyOutlinedVariantWithScheme:toCard:’ to style an instance with the outlined values.

Cards Classes

MDCCard

MDCCard subclasses UIControl and provides a simple class for developers to subclass and create custom cards with ink, shadows, corner radius, and stroke matching the Material spec.

MDCCard uses the highlighted property that is built-in in UIControl and the UIControlState to move between states.

MDCCardCollectionCell

MDCCardCollectionCell subclasses UICollectionViewCell and provides a simple collection view cell for developers to use in their collections with ink, shadows, corner radius, and stroke matching the Material spec.

MDCCardCollectionCell uses the selected property that is built-in in UICollectionViewCell and has its own MDCCardCellState to keep track of the current state it is in.

Installation

Installation with CocoaPods

Add the following to your Podfile:

pod 'MaterialComponents/Cards'

Then, run the following command:

pod install

Importing

To import the component:

Swift

import MaterialComponents.MaterialCards

Objective-C

#import "MaterialCards.h"

Usage

Typical use: as a view

MDCCard can be used like a regular UIView.

Swift

let card = MDCCard()

// Create, position, and add content views:
let imageView = UIImageView()
card.addSubview(imageView)

Objective-C

MDCCard *card = [[MDCCard alloc] init];

// Create, position, and add content views:
UIImageView *imageView = [[UIImageView alloc] init];
[card addSubview:imageView];

Typical use: in a collection view

Use MDCCardCollectionCell as a base class for your custom collection view cell

Swift

collectionView.register(MDCCardCollectionCell.self, forCellWithReuseIdentifier: "Cell")

func collectionView(_ collectionView: UICollectionView,
                    cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
  let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell",
                                                for: indexPath) as! MDCCardCollectionCell
  // If you wanted to have the card show the selected state when tapped
  // then you need to turn isSelectable to true, otherwise the default is false.
  cell.isSelectable = true
  
  cell.selectedImageTintColor = .blue
  cell.cornerRadius = 8
  cell.setShadowElevation(6, for: .selected)
  cell.setShadowColor(UIColor.black, for: .highlighted)
  return cell
}

Objective-C

[self.collectionView registerClass:[MDCCardCollectionCell class]
        forCellWithReuseIdentifier:@"Cell"];

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView
                  cellForItemAtIndexPath:(NSIndexPath *)indexPath {
  MDCCardCollectionCell *cell =
  [collectionView dequeueReusableCellWithReuseIdentifier:@"Cell"
                                            forIndexPath:indexPath];
  // If you wanted to have the card show the selected state when tapped
  // then you need to turn selectable to true, otherwise the default is false.
  [cell setSelectable:YES];
  
  [cell setSelectedImageTintColor:[UIColor blueColor]];
  [cell setCornerRadius:8.f];
  [cell setShadowElevation:6.f forState:MDCCardCellStateSelected];
  [cell setShadowColor:[UIColor blackColor] forState:MDCCardCellStateHighlighted];
}

Extensions

Color Theming

You can theme a card with your app's color scheme using the ColorThemer extension.

You must first add the Color Themer extension to your project:

pod 'MaterialComponents/Cards+ColorThemer'

Swift

// Step 1: Import the ColorThemer extension
import MaterialComponents.MaterialCards_ColorThemer

// Step 2: Create or get a color scheme
let colorScheme = MDCSemanticColorScheme()

// Step 3: Apply the color scheme to your component
MDCCardsColorThemer.applySemanticColorScheme(colorScheme, to: component)

Objective-C

// Step 1: Import the ColorThemer extension
#import "MaterialCards+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
[MDCCardsColorThemer applySemanticColorScheme:colorScheme
     toCard:component];