2. Building pages

A preview of what you’ll build:

This tutorial has an accompanying GitHub repository called carbon-tutorial that we’ll use as a starting point for each step. If you haven’t forked and cloned that repository yet, and haven’t added the upstream remote, go ahead and do so by following the step 1 instructions.

With your repository all set up, let’s check out the branch for this tutorial step’s starting point.

Note: This builds on top of step 1, but be sure to check out the upstream step 2 branch because it includes the static assets required to get through this step.

Install the app’s dependencies (in case you’re starting fresh in your current directory and not continuing from the previous step):

Then, start the app:

You should see something similar to where the previous step left off.

Before we get started with this step, we’ll be adding some components that require IE11 polyfills. As shown in the Carbon React documentation, go ahead and add these imports to the top of the root index.js. They aren’t all needed, but we’ll add them all to play it safe for the duration of the tutorial.

Note: You may be wondering where core-jscame from because it’s not a Carbon package and we haven’t explicitly installed it. Run yarn why core-js and you’ll see there are a number of packages that have brought it in as a dependency.

In our last step we added our styles, component and icon packages. Now that we’re building the pages with grid, we need to install one more Carbon package. Stop your development environment (CTRL-C) and:

In index.scss, we need to configure our grid to use 16 columns instead of the default 12 columns. We do this by adding grid-columns-16: true in our $feature-flags.

Note: Like before, the feature flag still needs to come before the Carbon styles.scss import.

Run yarn start so we can begin building.

Let’s add our grid elements to LandingPage.js.

In order to use the grid, we need to wrap everything in a <div className="bx--grid">. We can continue to make rows by adding a <div className="bx--row"> inside the grid, as well as make columns within those rows by adding <div className="bx--col-[breakpoint]-[size]">.

Our column sizes are specified by the number of columns they’ll be spanning. If we use bx--col-lg-4, it means it’ll span 4 of the 16 columns. If we use bx--col-lg-8 it means it’ll span 8 of the 16 columns, and so on.

We’ve included the designs for this tutorial app in the design.sketch file found as a top-level file in the carbon-tutorial repository. But, if you don’t have Sketch installed and available to inspect the design, we’ll provide screenshots.

Pro tip: CTRL-L toggles the layout in Sketch.

We’ll break this down into three rows. The first row with the gray background doesn’t appear to need any columns. The second row with the white background looks like it has two columns of different widths. The third row with the gray background looks like it has four columns of equal width.

We’ll make rows like so:

We added a class of bx--grid--full-width to the grid container since our rows need to expand the whole page without any margins. We also added some custom classes like landing-page, landing-page__banner, landing-page__r2, etc., which we will use later.

Also, take notice of the second row. The tab content only covers 7 columns at this large viewport to prevent overly-large line lengths, so we needed to add a 1 column offset bx--offset-lg-1 to second column to fill the full 16 columns in the grid. Then, both of those columns have bx--col-md-4 classes so they are of equal width at medium-sized viewports.

We’ll start adding HTML elements and components by row.

In our first row we’ll need a BreadCrumb component. First, let’s import the components we need. Because we’ll be importing several components for this page, we’ll import them directly from the carbon-components-react package instead of the direct path for each one.

We can now add our component to the first row, along with a header, like so:

You may notice that the styles look off. Don’t worry, we’ll fix these later.

In our second row we’ll need Tabs and Button components. We’ll update the carbon-components-react import to:

Before we can render the tabs, we need to add some props for the component after the import. These example props came from the React Tabs Story in Storybook.

Modify the second row to use the Tab component.

Note: We’re using the grid for the page layout, but we also need to apply the grid within the tab content. When doing so, make sure the nested grid has the expected grid > row > col DOM structure.

Hold up! If you were to run DAP to check for accessibility violations, you’d see Multiple navigation landmarks must have unique labels specified with aria-label or aria-labelledby because both the Breadcrumb and Tabs components use <nav> elements. To fix, add aria-label to the Breadcrumb opening tag:

Same goes for the Tabs opening tag:

Next, we’ll need to add a styling override to move the tabs to the right on large viewports. Create a file _overrides.scss in src/content/LandingPage with this declaration block.

Then in _landing-page.scss add this import at the top of the file.

Note: We don’t have to include this in a separate file, but it’s nice to keep overrides separate from your application’s styling so when migrating to future Carbon versions and if there are breaking changes via different class names, you have a consolidated list of styling declaration blocks to review.

We can now add our images and text for each column in the first Tab in LandingPage.js.

Now let’s set the image size in _landing-page.scss:

Assuming that the second and third tab would have a similar design, we would set them up in the same way. However, since our design specs don’t show those tabs, we’ll leave the code as is.

The third row will be created in a later tutorial, so we’ll just add the headers for now.

We’ve added basic layout styles in _landing-page.scss, so now let’s add type, color and spacing styles to match the design. We’ll be using our spacing tokens. In app.scss, add these imports at the top of the file so we can use Carbon breakpoints, tokens, and typography Sass mixins and functions:

Pro tip: CTRL-G toggles the grid in Sketch.

Back to _landing-page.scss, we need to add space above the breadcrumb and below the heading. For that, add:

Referencing the spacing token table, 16px can be set with the $spacing-05 token. The design calls for 128px of space below the heading and that’s not in the spacing scale, we can achieve that in Sass by multiplying 32px ($spacing-07) by 4. We could use 128px or 8rem directly in our styling, but using our tokens preserves consistency should the token values get updated in the future.

Looking at the design, we need a wall-to-wall light gray background behind the banner and also behind the third row. This is a great opportunity to use a Sass mixin. We could put this at the top of _landing-page.scss, but it’s best practice to place mixins in a dedicated file, so create a _mixins.scss file in src/content/LandingPage.

Add the following in _mixins.scss. Per the design we need to use Gray 10 for our banner background color, which can be set with the $ui-01 color token. Also, we want the background to extend into the grid’s outermost gutters to go the full width of the viewport, so given the DOM structure, we can achieve that by setting the background in an absolutely positioned pseudo element.

After you have created _mixins.scss, import it at the top of _landing-page.scss. By now you should have two imports:

Now to use the new mixin, update the .landing-page__banner declaration block to:

Next, we can see that the h1 is using the heading-05 type token.

The Sketch symbol naming is consistent with the development Sass tokens to help translate design to development. So, looking up the type token, we know to use productive-heading-05:

For our second row, we need to fix the tabs vertical positioning to match the design. By inspecting the tabs component, you can see that the tab height computes to 40px. We can use that to create our negative top margin in rem units.

We also need to adjust our vertical spacing and type treatment. Like before, it’s a matter of using spacing and type tokens like so:

Note: You may be wondering why there are vertical gaps between the type and spacers. Each type token has a line height that’s suited for its font size. The vertical spacers adjacently touch the line height boundaries and not the baseline, for consistency as well as development ease so margins and paddings don’t need to offset line heights.

Let’s also add some styles for the last row, even though that will get used later in the tutorial. You’ll notice that we get to re-use the landing-page-background mixin that we just created.

Ta-da! You should see a finished landing page! Now we can move on to the repo page.

Now in our RepoPage.js we’ll add our grid containers in the return section.

We currently have RepoPage.js that just contains a grid and placeholder content for the time being. In the next tutorial step we’re going to be querying an API to populate the DataTable component in this page. As a best practice to separate data fetching from the presentation components, go ahead and create a RepoTable.js as a sibling to RepoPage.js in src/content/RepoPage.

First, we’ll add our data table by importing a few components in RepoTable.js:

Then, let’s create the RepoTable component and export it at the very bottom of RepoTable.js.

This component uses two props, rows and headers, and returns a Carbon DataTable. As for where the various Table* components came from? The DataTable story in Storybook was used to put together the data table structure.

Note: The getTableProps, getHeaderProps, and getRowProps functions each tell the DataTable component to process and return the necessary props that are needed by the Table, Header and Row components respectively. We take the return of that function (an object containing the props) and spread it out into the component.

At this point, return to RepoPage.js because now we need to render a static RepoTable.

Import RepoTable in RepoPage.js.

Then below the imports, include the following arrays to pass into the RepoTable component. We’ll be setting the rows array from an API in the next tutorial step, but for now, static example rows will suffice.

Lastly in RepoPage.js, we need to simply replace Data table will go here with:

Our styles for the repo page are mostly fine. We just need to update a few vertical spacing issues.

In _repo-page.scss, add the following styles:

Congratulations! We’ve now created our static repo page!

We’re going to submit a pull request to verify completion of this tutorial step.

Run the CI check to make sure we’re all set to submit a pull request.

Note: Having issues running the CI check? Step 1 has troubleshooting notes that may help.

Before we can create a pull request, stage and commit all of your changes:

Then, push to your repository:

Note: Having issues pushing your changes? Step 1 has troubleshooting notes that may help.

Finally, visit carbon-tutorial to “Compare & pull request”. In doing so, make sure that you are comparing to react-step-2 into base: react-step-2.

Note: Expect your tutorial step PRs to be reviewed by the Carbon team but not merged. We’ll close your PR so we can keep the repository’s remote branches pristine and ready for the next person!