Flutter With Visual Studio Code

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Hi friends,In this video a brief demo is shown to help beginners to open and runFlutter App project in Visual Studio Code (VS Code) IDE.

  • Flutter visual-studio-code. Improve this question. Follow asked Dec 17 '19 at 13:44. Drigols drigols. 49 2 2 silver badges 9 9 bronze badges.
  • Create A New Flutter Project In Visual Studio Code To download and install the Visual Studio Code check the link After you have successfully installed the Visual Studio Code into your computer. Now follow the steps as mentioned below.
Contents
  • Installation and setup
  • Creating projects
  • Running and debugging
  • Advanced debugging
  • Editing tips for Flutter code
  • Troubleshooting

Installation and setup

Follow the Set up an editor instructions toinstall 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 whenupdates are available.

To install updates manually:

  1. Click the Extensions button in the Side Bar.
  2. If the Flutter extension is shown with an available update,click the update button and then the reload button.
  3. 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 Flutterstarter app template:

  1. Open the Command Palette(Ctrl+Shift+P (Cmd+Shift+P on macOS)).
  2. Select the Flutter: New Application Project command and press Enter.
  3. Enter your desired Project name.
  4. Select a Project location.

Opening a project from existing source code

To open an existing Flutter project:

  1. Click File > Open from the main IDE window.
  2. Browse to the directory holding your existingFlutter source code files.
  3. Click Open.

Editing code and viewing issues

The Flutter extension performs code analysis thatenables the following:

  • Syntax highlighting
  • Code completions based on rich type analysis
  • Navigating to type declarations(Go to Definition or F12),and finding type usages(Find All References or Shift+F12)
  • Viewing all current source code problems(View > Problems or Ctrl+Shift+M(Cmd+Shift+M on macOS))Any analysis issues are shown in the Problems pane:
Visual studio plugin development

Running and debugging

Note: You can debug your app in a couple of ways.

  • Using DevTools, a suite of debugging and profilingtools that run in a browser. DevTools replaces the previousbrowser-based profiling tool, Observatory, and includesfunctionality previously only available to Android Studioand IntelliJ, such as the Flutter inspector.
  • Using VS Code’s built-in debugging features,such as setting breakpoints.

The instructions below describe features available in VS Code. For information on using launching DevTools, see Running DevTools from VS Code in the DevTools docs.

Start debugging by clicking Run > Start Debuggingfrom 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 adevice name (or the message No Devices):

Note:

  • If you do not see a Flutter version number or device info,your project might not have been detected as a Flutter project.Ensure that the folder that contains your pubspec.yaml isinside a VS Code Workspace Folder.
  • If the status bar reads No Devices, Flutter has not beenable to discover any connected iOS or Android devices or simulators.You need to connect a device, or start a simulator or emulator,to proceed.

The Flutter extension automatically selects the last device connected.However, if you have multiple devices/simulators connected, clickdevice in the status bar to see a pick-listat the top of the screen. Select the device you want to use forrunning or debugging.

Run app without breakpoints

  1. Click Run > Start Without Debugging in themain IDE window, or press Ctrl+F5.The status bar turns orange to show you are in a debug session.

Run app with breakpoints

  1. If desired, set breakpoints in your source code.

  2. Click Run > Start Debugging in the main IDE window,or press F5.

    • 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 theDebug 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.

  1. Open the launch.json file in VS Code.

    If you do not have a launch.json file, go to the Run view in VS Code and click create a launch.json file.

  2. In the configurations section, change the flutterMode 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:
  3. Run the app through the Run view.

Fast edit and refresh development cycle

Flutter offers a best-in-class developer cycle enabling youto see the effect of your changes almost instantly with theStateful Hot Reload feature. SeeUsing hot reload for details.

Advanced debugging

Debugging visual layout issues

During a debug session,several additional debugging commands are added to theCommand Palette and to the Flutter inspector.When space is limited, the icon is used as the visualversion 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 disabledin the Flutter extension. To enable:

  1. Select Settings > Extensions > Dart Configuration.
  2. 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 aFlutter widget identifier, as indicated by the yellow lightbulb icon.The assist can be invoked by clicking the lightbulb, or by using thekeyboard shortcut Ctrl+. (Cmd+. on Mac), as illustrated here:

Quick fixes are similar,only they are shown with a piece of code has an error and theycan assist in correcting it.

Wrap with new widget assist
This can be used when you have a widget that you want to wrapin a surrounding widget, for example if you want to wrap awidget in a Row or Column.
Wrap widget list with new widget assist
Similar to the assist above, but for wrapping an existinglist 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 a StatefulWidget,by creating the State 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 of StatefulWidgetand its associated State subclass.
  • Prefix stanim: Create a new subclass of StatefulWidget,and its associated State subclass including a field initializedwith an AnimationController.

You can also define custom snippets by executingConfigure User Snippets from the Command Palette.

Keyboard shortcuts

Hot reload
During a debug session, clicking the Hot Reload button on theDebug Toolbar, or pressing Ctrl+F5(Cmd+F5 on macOS) performs a hot reload.

Keyboard mappings can be changed by executing theOpen Keyboard Shortcuts command from the Command Palette.

Hot reload vs. hot restart

FlutterStudio

Hot reload works by injecting updated source code files into therunning Dart VM (Virtual Machine). This includes not onlyadding new classes, but also adding methods and fields toexisting 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, fully restart your application withouthaving to end your debugging session. To perform a hot restart,run the Flutter: Hot Restart command from theCommand Palette, or press Ctrl+Shift+F5(Cmd+Shift+F5 on macOS).

Visual Studio

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 theissue is already tracked.
  • Make sure you are up to date with the most recentversion of the plugin.

When filing new issues, include flutter doctor output.

Flutter Visual Studio Code Hot Reload Not Working

Contents

While your code might follow any preferred style—in ourexperience—teams of developers might find it more productive to:

  • Have a single, shared style, and
  • Enforce this style through automatic formatting.

The alternative is often tiring formatting debates during code reviews,where time might be better spent on code behavior rather than code style.

Automatically formatting code in Android Studio and IntelliJ

Install the Dart plugin (see Editor setup)to get automatic formatting of code in Android Studio and IntelliJ.To automatically format your code in the current source code window,use Cmd+Alt+L (on Mac) or Ctrl+Alt+L (on Windows and Linux).Android Studio and IntelliJ also provides a check box named Format code on save onthe Flutter page in Preferences (on Mac) or Settings (on Windows and Linux)which will format the current file automatically when you save it.

Automatically formatting code in VS Code

Install the Flutter extension (see Editor setup)to get automatic formatting of code in VS Code.

To automatically format the code in the current source code window,right-click in the code window and select Format Document.You can add a keyboard shortcut to this VS Code Preferences.

To automatically format code whenever you save a file, set theeditor.formatOnSave setting to true.

Automatically formatting code with the ‘flutter’ command

You can also automatically format code in the command line interface(CLI) using the flutter format command:

Using trailing commas

Flutter code often involves building fairly deep tree-shaped data structures,for example in a build method. To get good automatic formatting,we recommend you adopt the optional trailing commas.The guideline for adding a trailing comma is simple: Alwaysadd a trailing comma at the end of a parameter list infunctions, methods, and constructors where you care aboutkeeping the formatting you crafted.This helps the automatic formatter to insert an appropriateamount of line breaks for Flutter-style code.

Here is an example of automatically formatted code with trailing commas:

Flutter With Visual Studio Code 2020

And the same code automatically formatted code without trailing commas: