---
id: mig_guide_2_0
sidebar_position: 3
title: Migrating to 2.0 (Null-safety)
---

A Migration Guide For Switching To v2.0 Of The Flutter SDK

### Overview

v2.0 of the Stream Chat Flutter SDK brings along several changes - primarily making the SDK null-safe.
Null safety allows your apps to run faster, with fewer errors, and with less code.

Check [this link](https://flutter.dev/docs/null-safety) for more about Null Safety in Flutter.

This guide is intended to enumerate and better explain the changes in the SDK.

The changes will be listed by package and a concise changelog will follow with more info.

### Changelog of `stream_chat_flutter`

#### 🛑️ Breaking Changes from 1.5.4

* Migrate this package to null safety

* Renamed `ChannelImage` to `ChannelAvatar`

* Updated `StreamChatThemeData.reactionIcons` to accept custom builder

* Renamed `ColorTheme` properties to reflect the purpose of the colors

    * `ColorTheme.black` -> `ColorTheme.textHighEmphasis`
    * `ColorTheme.grey` -> `ColorTheme.textLowEmphasis`
    * `ColorTheme.greyGainsboro` -> `ColorTheme.disabled`
    * `ColorTheme.greyWhisper` -> `ColorTheme.borders`
    * `ColorTheme.whiteSmoke` -> `ColorTheme.inputBg`
    * `ColorTheme.whiteSnow` -> `ColorTheme.appBg`
    * `ColorTheme.white` -> `ColorTheme.barsBg`
    * `ColorTheme.blueAlice` -> `ColorTheme.linkBg`
    * `ColorTheme.accentBlue` -> `ColorTheme.accentPrimary`
    * `ColorTheme.accentRed` -> `ColorTheme.accentError`
    * `ColorTheme.accentGreen` -> `ColorTheme.accentInfo`

* `ChannelListCore` options property is removed in favor of individual properties

     * `options.state` -> `bool state`
     * `options.watch` -> `bool watch`
     * `options.presence` -> `bool presence`

* `UserListView` options property is removed in favor of individual properties

     * `options.presence` -> `bool presence`

* Renamed `ImageHeader` to `GalleryHeader`

* Renamed `ImageFooter` to `GalleryFooter`

* `MessageBuilder` and `ParentMessageBuilder` signature is now

```
typedef MessageBuilder = Widget Function(
    BuildContext,
    MessageDetails,
    List<Message>,
    MessageWidget defaultMessageWidget,
    );
```

The last parameter is the default `MessageWidget`
You can call `.copyWith` to customize just a subset of properties

#### ✅ Added

Added video compress options (frame and quality) to MessageInput
`TypingIndicator` now has a property called `parentId` to show typing indicator specific to threads
#493: add support for `MessageListView` header/footer
`MessageWidget` accepts a `userAvatarBuilder`
Added `pinMessage` ui support
Added `MessageListView.threadSeparatorBuilder` property
Added `MessageInput.onError` property to allow error handling
Added `GalleryHeader`/`GalleryFooter` theme classes

#### 🐞 Fixed

#483: Keyboard covers input text box when editing message
`Modals` are shown using the nearest `Navigator` to make using the SDK easier in a nested navigator use case
#484: messages don't update without a reload
`MessageListView` not rendering if the user is not a member of the channel
Fix `MessageInput` overflow when there are no actions
Minor fixes and improvements

### Migrating to 2.0 for `stream_chat_flutter`

:::note
If you are migrating your full Flutter project to null-safety, first make sure you follow the
instructions from the [official Null Safety migration guide](https://dart.dev/null-safety/migration-guide).
:::

To migrate to v2.0 for `stream_chat_flutter`, first change the version of the package to the latest
null-safe version.

```yaml
dependencies:
  stream_chat_flutter: ^2.0.0
```

Upon doing this, all breaking changes from the package will take immediate effect. Here are steps to
remedy the issues:

1) Replace the offending class names with the revised class names

    * `ChannelImage` -> `ChannelAvatar`
    * `ImageHeader` -> `GalleryHeader`
    * `ImageFooter` -> `GalleryFooter`

2) The new version comes with revised color names since the previous names do not suit light/dark mode
nomenclature. Make sure any old colors used from theme are changed over to the new theme color names:

    * `ColorTheme.black` -> `ColorTheme.textHighEmphasis`
    * `ColorTheme.grey` -> `ColorTheme.textLowEmphasis`
    * `ColorTheme.greyGainsboro` -> `ColorTheme.disabled`
    * `ColorTheme.greyWhisper` -> `ColorTheme.borders`
    * `ColorTheme.whiteSmoke` -> `ColorTheme.inputBg`
    * `ColorTheme.whiteSnow` -> `ColorTheme.appBg`
    * `ColorTheme.white` -> `ColorTheme.barsBg`
    * `ColorTheme.blueAlice` -> `ColorTheme.linkBg`
    * `ColorTheme.accentBlue` -> `ColorTheme.accentPrimary`
    * `ColorTheme.accentRed` -> `ColorTheme.accentError`
    * `ColorTheme.accentGreen` -> `ColorTheme.accentInfo`

3) We decided to make messages easier to customize and now supply the default implementation of the
messages in the builder - so you can now customize a single parameter without having to redo the
entire implementation. Please reform your builders to take into account the new format:

```
typedef MessageBuilder = Widget Function(
    BuildContext,
    MessageDetails,
    List<Message>,
    MessageWidget defaultMessageWidget,
    );
```

To tweak any of the default properties individually, you can use `defaultMessageWidget.copyWith()`.

### Changelog of `stream_chat_flutter_core`

#### 🛑️ Breaking Changes from 1.5.3

* Migrate this package to null safety
* `channelsBloc.queryChannels()`, `ChannelListCore` options param/property is removed in favor of individual params/properties
    * `options.state` -> `bool state`
    * `options.watch` -> `bool watch`
    * `options.presence` -> `bool presence`
* `usersBloc.queryUsers()`, `UserListCore` options param/property is removed in favor of individual params/properties
    * `options.presence` -> `bool presence`

#### ✅ Added

* Monitor connection using `connectivity_plus` package

#### 🐞 Fixed

* Minor fixes
* Performance improvements

### Migrating to 2.0 for `stream_chat_flutter_core`

:::note
If you are migrating your full Flutter project to null-safety, first make sure you follow the
instructions from the [official Null Safety migration guide](https://dart.dev/null-safety/migration-guide).
:::

To migrate to v2.0 for `stream_chat_flutter_core`, first change the version of the package to the latest
null-safe version.

```yaml
dependencies:
  stream_chat_flutter_core: ^2.0.0
```

Upon doing this, all breaking changes from the package will take immediate effect. Here are steps to
remedy the issue:

:::note
The major changes in `stream_chat_flutter_core` consist of changing over from a map full of options
to a more type safe and sound approach by changing over to explicit parameters.
:::

1) Change over Core widget implementations by using the explicit parameters instead of the options map.
Use these explicit parameters in the widget constructor instead of the option keys:

    * `options.state` -> `bool state`
    * `options.watch` -> `bool watch`
    * `options.presence` -> `bool presence`

2) Change over query calls in the BLoCs in the same way (change from options map to explicit parameters
in the constructor)

### Changelog of `stream_chat`

#### 🛑️ Breaking Changes from 1.5.3

* Migrate this package to null safety
* `ConnectUserWithProvider` now requires `tokenProvider` as a required param. (Removed from the constructor)
* `client.disconnect()` is now divided into two different functions
    * `client.closeConnection()` -> for closing user websocket connection.
    * `client.disconnectUser()` -> for disconnecting user and resetting client state.
* `client.devToken()` now returns a Token model instead of String.
* `ApiError` is removed in favor of `StreamChatError`
    * `StreamChatError` -> parent type for all the stream errors.
    * `StreamWebSocketError` -> for user websocket related errors.
    * `StreamChatNetworkError` -> for network related errors.
* `client.queryChannels()`, `channel.query()` options param is removed in favor of individual params
    * `option.state` -> `bool state`
    * `option.watch` -> `bool watch`
    * `option.presence` -> `bool presence`
* `client.queryUsers()` options param is removed in favor of individual params
    * `option.presence` -> `bool presence`
* Added typed filters

#### 🐞 Fixed

* #369: Client does not return without internet connection
* Several minor fixes
* Performance improvements

#### ✅ Added

* New Location enum is introduced for easily changing the client location/baseUrl.
* New `client.openConnection()` and `client.closeConnection()` is introduced to connect/disconnect user ws connection.
* New `client.partialUpdateMessage` and `channel.partialUpdateMessage` methods
* `connectWebSocket` parameter in connect user calls to use the client in "connection-less" mode.

#### 🔄 Changed

* `baseURL` is now deprecated in favor of using Location to change data location.

### Migrating to 2.0 for `stream_chat`

If you are migrating your full Flutter project to null-safety, first make sure you follow the
instructions from the [official Null Safety migration guide](https://dart.dev/null-safety/migration-guide).
:::

To migrate to v2.0 for `stream_chat`, first change the version of the package to the latest
null-safe version.

```yaml
dependencies:
  stream_chat: ^2.0.0
```

Upon doing this, all breaking changes from the package will take immediate effect. Here are steps to
remedy the issues:

1) Change over the constructor of `connectUserWithProvider()` to the new format which has `tokenProvider` as a required param.

2) We added more nuance to `disconnectUser()` by adding two new methods - one to close the connection
and the other to disconnect the user. This allows more fine-grained control of disconnection.

    * `client.closeConnection()` -> for closing user websocket connection.
    * `client.disconnectUser()` -> for disconnecting user and resetting client state.

3) We refactored how we handle errors - new error types are now introduced that replace ApiError.

    * `StreamChatError` -> parent type for all the stream errors.
    * `StreamWebSocketError` -> for user websocket related errors.
    * `StreamChatNetworkError` -> for network related errors.

4) We changed over from a map full of options to a more type-safe and sound approach by changing over to explicit parameters.

Use these explicit parameters in the query parameters instead of the option keys:

* `client.queryChannels()`, `channel.query()` options param is removed in favor of individual params
    * `option.state` -> `bool state`
    * `option.watch` -> `bool watch`
    * `option.presence` -> `bool presence`
* `client.queryUsers()` options param is removed in favor of individual params
    * `option.presence` -> `bool presence`

5) We added type-safe filters to make filtering in the app easier. Change over the filters to the
new implementation.

As an example, in the old app this filter:

```dart
    filter: {
      'members': {
        '\$in': [StreamChat.of(context).user.id],
      }
    },
```

Would turn into:

```dart
    filter: Filter.in_('members', [StreamChat.of(context).user.id])
```
