得到

2026-07-15 16:57:36 +08:00
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+<!---
+This is the API of version 1.2.0
+-->
+# DropdownMenu
+
+The DropdownMenu Composable can be used to create DropdownMenu.
+
+<p align="center">
+  <img src ="{{ site.images }}/material/dropdownmenu/dropdown.png"  />
+</p>
+
+```kotlin
+fun DropdownMenu(
+    expanded: Boolean,
+    onDismissRequest: () -> Unit,
+    modifier: Modifier = Modifier,
+    offset: DpOffset = DpOffset(0.dp, 0.dp),
+    properties: PopupProperties = PopupProperties(focusable = true),
+    content: @Composable ColumnScope.() -> Unit
+)
+```
+
+**expanded**
+If true, the popupmenu with the dropdownContent will be shown
+
+**onDismissRequest**
+Called when the menu should be dismiss
+
+```kotlin
+@Composable
+fun DropdownDemo() {
+    var expanded by remember { mutableStateOf(false) }
+    val items = listOf("A", "B", "C", "D", "E", "F")
+    val disabledValue = "B"
+    var selectedIndex by remember { mutableStateOf(0) }
+    Box(modifier = Modifier.fillMaxSize().wrapContentSize(Alignment.TopStart)) {
+        Text(items[selectedIndex],modifier = Modifier.fillMaxWidth().clickable(onClick = { expanded = true }).background(
+            Color.Gray))
+        DropdownMenu(
+            expanded = expanded,
+            onDismissRequest = { expanded = false },
+            modifier = Modifier.fillMaxWidth().background(
+                Color.Red)
+        ) {
+            items.forEachIndexed { index, s ->
+                DropdownMenuItem(onClick = {
+                    selectedIndex = index
+                    expanded = false
+                }) {
+                    val disabledText = if (s == disabledValue) {
+                        " (Disabled)"
+                    } else {
+                        ""
+                    }
+                    Text(text = s + disabledText)
+                }
+            }
+        }
+    }
+}
+```
+
+
+## See also:
+* [Material.io](https://material.io/components/menus#dropdown-menu)
+* [Official Docs](https://developer.android.com/reference/kotlin/androidx/compose/material/package-summary#dropdownmenu)
+* [Full Example Code]({{ site.samplefolder }}/material/dropdown/DropdownDemo.kt)