migrating-to-20.mdx

Migrating to 2.0

By popular demand, there is a breaking change in the go_router 2.0 release: the params property of the GoRouterState object has been split into two properties:

• params for parameters that are part of the path and, e.g. /family/:fid
• queryParams for parameters that added optionally at the end of the location, e.g. /login?from=/family/f2

In the 1.x releases, the params property was a single object that contained both the path and query parameters in a single map. For example, if you had been using the params property to access query parameters like this in 1.x:

GoRoute(
  path: '/login',
  pageBuilder: (context, state) => MaterialPage<void>(
    key: state.pageKey,
    // 1.x: accessing query parameters
    child: LoginScreen(from: state.params['from']),
  ),
),

in 2.0, you would access the query parameters like this:

GoRoute(
  path: '/login',
  pageBuilder: (context, state) => MaterialPage<void>(
    key: state.pageKey,
    // 2.0: accessing query parameters
    child: LoginScreen(from: state.queryParams['from']),
  ),
),

Likewise, if you were using named routes in 1.x, you may have been passing both path and query parameters like so:

ListTile(
  title: Text(p.name),
  // 1.x: passing both path and query parameters
  onTap: () => context.goNamed(
    'person',
    // anything not a path param was assumed to be a query param
    {'fid': family.id, 'pid': p.id, 'qid': 'quid'},
  ),
),

Now you'll need to change your code to do the following in 2.0:

ListTile(
  title: Text(p.name),
  // 2.0: passing both path and query parameters
  onTap: () => context.goNamed(
    'person',
    params: {'fid': family.id, 'pid': p.id},
    queryParams: {'qid': 'quid'},
  ),
),

I got a little clever merging the two kinds of parameters into a single scope and hopefully this change makes things a little more clear.