Visual Studio Code
- Installation and setup
- Creating projects
- Editing code and viewing issues
- Running and debugging
- Fast edit and refresh development cycle
- Advanced debugging
- Editing tips for Flutter code
- Troubleshooting
Installation and setup
#Follow the Set up an editor instructions to install the Dart and Flutter extensions (also called plugins).
Updating the extension
#Updates to the extensions are shipped on a regular basis. By default, VS Code automatically updates extensions when updates are available.
To install updates yourself:
- Click Extensions in the Side Bar.
- If the Flutter extension has an available update, click Update and then Reload.
- Restart VS Code.
Creating projects
#There are a couple ways to create a new project.
Creating a new project
#To create a new Flutter project from the Flutter starter app template:
Go to View > Command Palette....
You can also press Ctrl / Cmd + Shift + P.
Type
flutter
.Select the Flutter: New Project.
Press Enter.
Select Application.
Press Enter.
Select a Project location.
Enter your desired Project name.
Opening a project from existing source code
#To open an existing Flutter project:
Go to File > Open.
You can also press Ctrl / Cmd + O
Browse to the directory holding your existing Flutter source code files.
Click Open.
Editing code and viewing issues
#The Flutter extension performs code analysis. The code analysis can:
Highlight language syntax
Complete code based on rich type analysis
Navigate to type declarations
- Go to Go > Go to Definition.
- You can also press F12.
Find type usages.
- Press Shift + F12.
View all current source code problems.
- Go to View > Problems.
- You can also press Ctrl / Cmd + Shift + M.
- The Problems pane displays any analysis issues:
Running and debugging
#Start debugging by clicking Run > Start Debugging from the main IDE window, or press F5.
Selecting a target device
#When a Flutter project is open in VS Code, you should see a set of Flutter specific entries in the status bar, including a Flutter SDK version and a device name (or the message No Devices):
The Flutter extension automatically selects the last device connected. However, if you have multiple devices/simulators connected, click device in the status bar to see a pick-list at the top of the screen. Select the device you want to use for running or debugging.
Run app without breakpoints
#Go to Run > Start Without Debugging.
You can also press Ctrl + F5.
Run app with breakpoints
#If desired, set breakpoints in your source code.
Click Run > Start Debugging. You can also press F5. The status bar turns orange to show you are in a debug session.
- The left Debug Sidebar shows stack frames and variables.
- The bottom Debug Console pane shows detailed logging output.
- Debugging is based on a default launch configuration. To customize, click the cog at the top of the Debug Sidebar to create a
launch.json
file. You can then modify the values.
Run app in debug, profile, or release mode
#Flutter offers many different build modes to run your app in. You can read more about them in Flutter's build modes.
Open the
launch.json
file in VS Code.If you don't have a
launch.json
file:Go to View > Run.
You can also press Ctrl / Cmd + Shift + D
The Run and Debug panel displays.
Click create a launch.json file.
In the
configurations
section, change theflutterMode
property to the build mode you want to target.For example, if you want to run in debug mode, your
launch.json
might look like this:json"configurations": [ { "name": "Flutter", "request": "launch", "type": "dart", "flutterMode": "debug" } ]
Run the app through the Run panel.
Fast edit and refresh development cycle
#Flutter offers a best-in-class developer cycle enabling you to see the effect of your changes almost instantly with the Stateful Hot Reload feature. To learn more, check out Hot reload.
Advanced debugging
#You might find the following advanced debugging tips useful:
Debugging visual layout issues
#During a debug session, several additional debugging commands are added to the Command Palette and to the Flutter inspector. When space is limited, the icon is used as the visual version of the label.
- Toggle Baseline Painting
- Causes each RenderBox to paint a line at each of its baselines.
- Toggle Repaint Rainbow
- Shows rotating colors on layers when repainting.
- Toggle Slow Animations
- Slows down animations to enable visual inspection.
- Toggle Debug Mode Banner
- Hides the debug mode banner even when running a debug build.
Debugging external libraries
#By default, debugging an external library is disabled in the Flutter extension. To enable:
- Select Settings > Extensions > Dart Configuration.
- Check the
Debug External Libraries
option.
Editing tips for Flutter code
#If you have additional tips we should share, let us know!
Assists & quick fixes
#Assists are code changes related to a certain code identifier. A number of these are available when the cursor is placed on a Flutter widget identifier, as indicated by the yellow lightbulb icon. To invoke the assist, click the lightbulb as shown in the following screenshot:
You can also press Ctrl / Cmd + .
Quick fixes are similar, only they are shown with a piece of code has an error and they can assist in correcting it.
- Wrap with new widget assist
- This can be used when you have a widget that you want to wrap in a surrounding widget, for example if you want to wrap a widget in a
Row
orColumn
. - Wrap widget list with new widget assist
- Similar to the assist above, but for wrapping an existing list of widgets rather than an individual widget.
- Convert child to children assist
- Changes a child argument to a children argument, and wraps the argument value in a list.
- Convert StatelessWidget to StatefulWidget assist
- Changes the implementation of a
StatelessWidget
to that of aStatefulWidget
, by creating theState
class and moving the code there.
Snippets
#Snippets can be used to speed up entering typical code structures. They are invoked by typing their prefix, and then selecting from the code completion window:
The Flutter extension includes the following snippets:
- Prefix
stless
: Create a new subclass of -StatelessWidget`. - Prefix
stful
: Create a new subclass ofStatefulWidget
and its associated State subclass. - Prefix
stanim
: Create a new subclass ofStatefulWidget
, and its associated State subclass including a field initialized with anAnimationController
.
You can also define custom snippets by executing Configure User Snippets from the Command Palette.
Keyboard shortcuts
#- Hot reload
To perform a hot reload during a debug session, click Hot Reload on the Debug Toolbar.
You can also press Ctrl + F5 (Cmd + F5 on macOS).
Keyboard mappings can be changed by executing the Open Keyboard Shortcuts command from the Command Palette.
Hot reload vs. hot restart
#Hot reload works by injecting updated source code files into the running Dart VM (Virtual Machine). This includes not only adding new classes, but also adding methods and fields to existing classes, and changing existing functions. A few types of code changes cannot be hot reloaded though:
- Global variable initializers
- Static field initializers
- The
main()
method of the app
For these changes, restart your app without ending your debugging session. To perform a hot restart, run the Flutter: Hot Restart command from the Command Palette.
You can also press Ctrl + Shift + F5 or Cmd + Shift + F5 on macOS.
Troubleshooting
#Known issues and feedback
#All known bugs are tracked in the issue tracker: Dart and Flutter extensions GitHub issue tracker. We welcome feedback, both on bugs/issues and feature requests.
Prior to filing new issues:
- Do a quick search in the issue trackers to see if the issue is already tracked.
- Make sure you are up to date with the most recent version of the plugin.
When filing new issues, include flutter doctor output.
Unless stated otherwise, the documentation on this site reflects the latest stable version of Flutter. Page last updated on 2024-06-26. View source or report an issue.