compose-jb/tutorials/Context_Menu/README.md

Context Menu in Compose for Desktop

What is covered

In this tutorial we will cover all aspects of work with Context Menu using the Compose UI framework.

Default context menu

There is out-of-the box context menu support for TextField and Selectable text.

To enable standard context menu for a TextField you just need to put it inside DesktopMaterialTheme:

@OptIn(ExperimentalComposeUiApi::class, androidx.compose.foundation.ExperimentalFoundationApi::class)
fun main() = singleWindowApplication(title = "Context menu") {
   DesktopMaterialTheme { //it is mandatory for Context Menu
       val text = remember {mutableStateOf("Hello!")}
       TextField(
           value = text.value,
           onValueChange = { text.value = it },
           label = { Text(text = "Input") }
       )
   }
} 

Standard context menu for TextField contains the following items based on text selection: Copy, Cut, Paste, Select All.

Enabling standard context menu for a Text component is similar - you just need to make it selectable:

@OptIn(ExperimentalComposeUiApi::class, androidx.compose.foundation.ExperimentalFoundationApi::class)
fun main() = singleWindowApplication(title = "Context menu") {
   DesktopMaterialTheme { //it is mandatory for Context Menu
        SelectionContainer {
            Text("Hello World!")
        }
   }
} 

Context menu for text contains just Copy action.

User-defined context menu

To enable additional context menu items for TextField and Text components, ContextMenuDataProvider and ContextMenuItem elements are used:

@OptIn(ExperimentalComposeUiApi::class, androidx.compose.foundation.ExperimentalFoundationApi::class)
fun main() = singleWindowApplication(title = "Context menu") {
   DesktopMaterialTheme { //it is mandatory for Context Menu
       val text = remember {mutableStateOf("Hello!")}
        Column {
            ContextMenuDataProvider(
                items = {
                    listOf(
                        ContextMenuItem("User-defined Action") {/*do something here*/},
                        ContextMenuItem("Another user-defined action") {/*do something else*/}
                    )
                }
            ) {
                TextField(
                    value = text.value,
                    onValueChange = { text.value = it },
                    label = { Text(text = "Input") }
                )

                Spacer(Modifier.height(16.dp))

                SelectionContainer {
                    Text("Hello World!")
                }
            }
        }
   }
} 

In this example Text/TextField context menus will be extended with two additional items.

Context menu for an arbitary area

There is a possibility to create a context menu for an arbitary application window area. This is implemented using ContextMenuArea API that is similar to ContextMenuDataProvider.

@OptIn(ExperimentalComposeUiApi::class, androidx.compose.foundation.ExperimentalFoundationApi::class)
fun main() = singleWindowApplication(title = "Context menu") {
   DesktopMaterialTheme { //it is mandatory for Context Menu
        ContextMenuArea(items = {
            listOf(
                ContextMenuItem("User-defined Action") {/*do something here*/},
                ContextMenuItem("Another user-defined action") {/*do something else*/}
            )
        }) {
            Box(modifier = Modifier.background(Color.Blue).height(100.dp).width(100.dp)) {
            }
        }
   }
} 

Right click on the Blue Square will show a context menu with two items