Compose Multiplatform desktop application

Note If you have any issues, please report them on GitHub.

Compose for Desktop can produce applications for macOS, Linux, and Windows. You can use any of these platforms with our template.

Follow our tutorial below to create a simple desktop application using the Compose Multiplatform UI framework.

If you want to create an application targeting mobile platforms – iOS and Android – use the Compose Multiplatform mobile application template.

Before you start

Install the following tools:

JDK 11 or later
IntelliJ IDEA Community Edition or IntelliJ IDEA Ultimate 2020.3 or later (other editors may also work, but we'll use IntelliJ IDEA in this tutorial)
The Compose Multiplatform IDE support plugin

Compose development can be simplified by adding support for the @Preview annotation on argument-less @Composable functions. The plugin shows how a particular composable function looks in the IDE.

Creating a new project with an IDE

Starting with 2020.3, IntelliJ IDEA comes with a new project wizard that can automatically create a Compose application.

Note When creating a project, select JDK 11 or later. To use the native distribution packaging, select JDK 15 or later.

Update the plugin

Before you start, ensure that you’re using the latest version of the Compose Multiplatform IDE support plugin:

Check the latest release version in the Compose Multiplatform GitHub repository or on the Kotlin website.

Open the build.gradle.kts file for your project and update the version:

plugins {
   kotlin("jvm") version "1.8.20"
   id("org.jetbrains.compose") version "1.4.0"
}

Creating a new Compose project without an IDE

It is also possible to create a Compose project manually in the terminal.

We recommend building Compose for Desktop projects with Gradle. JetBrains provides a simple way of building such projects using a special Gradle plugin.

Note You can clone the existing template for a desktop or multiplatform application, or create one from scratch.

Create a new directory named sample:
```
mkdir sample
cd sample
```

Create the settings.gradle.kts file and modify it as follows:

pluginManagement {
   repositories {
       gradlePluginPortal()
       maven("https://maven.pkg.jetbrains.space/public/p/compose/dev")
   }
}

Create the build.gradle.kts file with the following content:

plugins {
   kotlin("jvm") version "1.8.20"
   id("org.jetbrains.compose") version "1.4.0"
}


repositories {
   mavenCentral()
   maven("https://maven.pkg.jetbrains.space/public/p/compose/dev")
   google()
}


dependencies {
   implementation(compose.desktop.currentOs)
}


compose.desktop {
   application {
       mainClass = "MainKt"
   }
}

Create src/main/kotlin/main.kt and add the following code to it:

import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.material.Button
import androidx.compose.material.MaterialTheme
import androidx.compose.material.Text
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import androidx.compose.ui.window.Window
import androidx.compose.ui.window.application
import androidx.compose.ui.window.rememberWindowState


fun main() = application {
   Window(
       onCloseRequest = ::exitApplication,
       title = "Compose for Desktop",
       state = rememberWindowState(width = 300.dp, height = 300.dp)
   ) {
       val count = remember { mutableStateOf(0) }
       MaterialTheme {
           Column(Modifier.fillMaxSize(), Arrangement.spacedBy(5.dp)) {
               Button(modifier = Modifier.align(Alignment.CenterHorizontally),
                   onClick = {
                       count.value++
                   }) {
                   Text(if (count.value == 0) "Hello World" else "Clicked ${count.value}!")
               }
               Button(modifier = Modifier.align(Alignment.CenterHorizontally),
                   onClick = {
                       count.value = 0
                   }) {
                   Text("Reset")
               }
           }
       }
   }
}

Run the application

In the editor

You can run and debug the application by clicking Run in the gutter near the main() function declaration:

Using Gradle tasks

In IntelliJ IDEA, open build.gradle.kts. After the necessary dependencies from the Maven repositories are downloaded, your project will be ready.
In the Gradle tool window, select sample/Tasks/compose desktop/run:

The first run may take some time.

Click the button several times to see that the application reacts and updates the UI:

You can also run Gradle tasks in the terminal:

./gradlew run to run the application
./gradlew package to store native distribution into build/compose/binaries

Next steps

We encourage you to explore Compose Multiplatform further and try out more projects:

re2zero / oxo-compose