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Questions tagged [flutter]

Use this tag for questions about the Flutter cross-platform UI toolkit. If your question is platform-specific, tag the platform as well (e.g., [android], [ios], etc.). You may also wish to include the [dart] tag for coding questions.

Flutter applications are written in the Dart programming language, and can connect to platform languages such as Java, Kotlin, Swift, and Objective-C. Also, thanks to ffi support, it is possible to interact with the C code directly . Flutter itself is built with C, C++, Dart, and Skia (a 2D rendering engine).

Flutter development is currently supported on Linux, macOS, Chrome OS and Windows operating systems.

Flutter is developed and maintained by Google and will be the main development SDK for Fuchsia, the expected and upcoming new Operating System also by Google.

Four main components of Flutter:

  • A heavily optimised, mobile-first 2D rendering engine (with excellent support for text) for 60fps apps
  • A functional-reactive framework so you can build customised UIs
  • A rich set of libraries and widgets (Material Design, Cupertino) widgets (optional, you can build-your-own widgets) so you can get started quickly and produce high-fidelity experiences
  • Productive CLI and IDE (IntelliJ) tools for sub-second developer cycles

Flutter is different than most other options for building mobile apps because Flutter uses neither WebView nor the OEM widgets that shipped with the device. Instead, Flutter uses its own high-performance rendering engine and framework to draw widgets to the screen.

Flutter also offers developers a highly productive and fast development experience, fast runtime and engine performance, and beautifully designed widgets that make for beautiful apps.

Resource

Source Code and Building

Community

Books

  • Flutter in Action - Complete Flutter and Dart resource, currently in 'Early Access'.

Related tags

168087 questions
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Flutter Material3 disable appbar color change on scroll

Using Material3 useMaterial3: true in Flutter version 3.0.1, when scrolling lets say listview, the appbar changes to darker color... Can this be disabled? Example from native android Material3 MaterialToolbar disable coloring at scroll:
dukaric1991
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Android Gradle plugin requires Java 11 to run. You are currently using Java 1.8, but i'm using java 11

I imported a Flutter project, and when I tried to run it, I got this message error: FAILURE: Build failed with an exception. * Where: Build file '/home/omer358/FlutterProjects/MyProjects/ConverterNOW/android/app/build.gradle' line: 24 * What went…
Omer Maki
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A Firebase App named "[DEFAULT]" already exists

I have my flutter App integrated with firebase, everything was fine but when I migrated firebase project to client firebase console, added his google services file, changed DefaultFirebaseOption.currentplatform file credentials but I got error…
K_Chandio
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The operation couldn’t be completed. Unable to locate a Java Runtime. Please visit http://www.java.com for information on installing Java

I couldn't run the flutter app on android emulator or android phone. I installed the recently released android studio for arm-mac platform on m1 mac. Please answer if I am doing anything wrong here or is it the problem with the release itself. Debug…
Yashwanth Ravula
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what is the difference between required and @required in flutter. What is the difference between them and when do we need to use them?

If I delete required from the named parameters, it gives me an error: The parameter 'color' // can't have a value of 'null' because of its type, but the implicit default value is 'null'. What is the difference between them and when do we need to…
ulukbek
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flutter error Invalid `Podfile` file: no implicit conversion of nil into String. ive searched through discussions but I cant seem to fix the issue

This is the error I am receiving. I tried flutter clean and changing the syntax of some lines but im new to dart and flutter so im not really sure. I reinstalled cocoa pods and ruby as well but Im receiving the same error. I also made sure to update…
aarushi
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How do I upgrade an existing Flutter app?

I have an existing Flutter app that I built half a year ago. I checked on pubspec.lock, it has this line: sdks: dart: ">=2.10.0-110 <2.11.0" flutter: ">=1.16.0 <2.0.0" So I assume the app was built for Flutter v1.16. How do I upgrade this app…
user1491884
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Flutter 'owner!._debugCurrentBuildTarget == this': is not true. #87

I am getting the error when I try to load the pdf from url. It shows the number of pages of pdf but then it crashes. Using plugin -…
Bharat Chhabra
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Flutter sign in with Apple not working on iOS simulator (infinite loader)

I'm using sign_in_with_apple. Have an issue on iOS simulator (software version 14.0). Infinite loader is displayed after a password is entered and 'Continue' is tapped. The flow gets stuck. Nothing happens next. What could be the reason for that?…
AndrewS
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Flutter android flavors generate apk

I am trying to set up Android flavors with flutter. I have two entry points. lib/main_prod.dart lib/main_dev.dart I have also added the following to my gradle file flavorDimensions "version" productFlavors { prod { dimension "version" …
Just_Ice
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What is the difference in calling Future and Future.microtask in Flutter?

From the documentation for the Future.microtask constructor, it says: * Creates a future containing the result of calling [computation] * asynchronously with [scheduleMicrotask]. and the documentation for the regular Future constructor…
Tree
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How to get type of file?

I'm trying to find a package which would recognise file type. For example final path = "/some/path/to/file/file.jpg"; should be recognised as image or final path = "/some/path/to/file/file.doc"; should be recognised as document
delmin
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How to get the File Extension from a string Path

I've got file path saved in variable and I want to get the file type extension by using path package https://pub.dev/packages/path So far I managed to do it by splitting the string like this final path =…
delmin
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Avoid using web-only libraries outside Flutter web plugin packages

I'm building a Flutter app that I am trying to make work on the web. Part of it contains some web specific code: import 'dart:html' as html; import 'package:flutter/foundation.dart'; class DownloadViewModel extends ChangeNotifier { static const…
Suragch
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How to show the Keyboard automatically for a Textfield in Flutter

I have a TextField in Flutter of which I want to automatically select the text and show the keyboard. I can select the text through a TextEditingController, but even with a FocusNodes requestFocus the keyboard isn't shown, when the Widget opens.…
relascope
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