Add placement support for context menu positioning

Introduces a Placement enum to specify how menus are positioned relative to an anchor, and updates native and Dart APIs to support passing placement options when opening context menus. Removes debug print from context menu region and updates bindings and menu logic to handle placement.

Author: lijy91

packages/cnativeapi/lib/src/bindings_generated.dart

@@ -1331,23 +1331,30 @@ class CNativeApiBindings {
   /// Open the menu as a context menu using the specified positioning strategy
   /// @param menu The menu
   /// @param strategy The positioning strategy determining where to display the menu
+  /// @param placement The placement option determining how the menu is positioned
+  /// relative to the reference point (default: NATIVE_PLACEMENT_BOTTOM_START)
   /// @return true if menu was opened successfully, false otherwise
   bool native_menu_open(
     native_menu_t menu,
     native_positioning_strategy_t strategy,
+    native_placement_t placement,
   ) {
-    return _native_menu_open(menu, strategy);
+    return _native_menu_open(menu, strategy, placement.value);
   }
 
   late final _native_menu_openPtr =
       _lookup<
         ffi.NativeFunction<
-          ffi.Bool Function(native_menu_t, native_positioning_strategy_t)
+          ffi.Bool Function(
+            native_menu_t,
+            native_positioning_strategy_t,
+            ffi.UnsignedInt,
+          )
         >
       >('native_menu_open');
   late final _native_menu_open = _native_menu_openPtr
       .asFunction<
-        bool Function(native_menu_t, native_positioning_strategy_t)
+        bool Function(native_menu_t, native_positioning_strategy_t, int)
       >();
 
   /// Close the menu if it's currently showing
@@ -1901,6 +1908,64 @@ final class native_rectangle_t extends ffi.Struct {
   external double height;
 }
 
+/// Placement options for positioning UI elements relative to an anchor.
+enum native_placement_t {
+  /// Position above the anchor, horizontally centered.
+  NATIVE_PLACEMENT_TOP(0),
+
+  /// Position above the anchor, aligned to the start (left).
+  NATIVE_PLACEMENT_TOP_START(1),
+
+  /// Position above the anchor, aligned to the end (right).
+  NATIVE_PLACEMENT_TOP_END(2),
+
+  /// Position to the right of the anchor, vertically centered.
+  NATIVE_PLACEMENT_RIGHT(3),
+
+  /// Position to the right of the anchor, aligned to the start (top).
+  NATIVE_PLACEMENT_RIGHT_START(4),
+
+  /// Position to the right of the anchor, aligned to the end (bottom).
+  NATIVE_PLACEMENT_RIGHT_END(5),
+
+  /// Position below the anchor, horizontally centered.
+  NATIVE_PLACEMENT_BOTTOM(6),
+
+  /// Position below the anchor, aligned to the start (left).
+  NATIVE_PLACEMENT_BOTTOM_START(7),
+
+  /// Position below the anchor, aligned to the end (right).
+  NATIVE_PLACEMENT_BOTTOM_END(8),
+
+  /// Position to the left of the anchor, vertically centered.
+  NATIVE_PLACEMENT_LEFT(9),
+
+  /// Position to the left of the anchor, aligned to the start (top).
+  NATIVE_PLACEMENT_LEFT_START(10),
+
+  /// Position to the left of the anchor, aligned to the end (bottom).
+  NATIVE_PLACEMENT_LEFT_END(11);
+
+  final int value;
+  const native_placement_t(this.value);
+
+  static native_placement_t fromValue(int value) => switch (value) {
+    0 => NATIVE_PLACEMENT_TOP,
+    1 => NATIVE_PLACEMENT_TOP_START,
+    2 => NATIVE_PLACEMENT_TOP_END,
+    3 => NATIVE_PLACEMENT_RIGHT,
+    4 => NATIVE_PLACEMENT_RIGHT_START,
+    5 => NATIVE_PLACEMENT_RIGHT_END,
+    6 => NATIVE_PLACEMENT_BOTTOM,
+    7 => NATIVE_PLACEMENT_BOTTOM_START,
+    8 => NATIVE_PLACEMENT_BOTTOM_END,
+    9 => NATIVE_PLACEMENT_LEFT,
+    10 => NATIVE_PLACEMENT_LEFT_START,
+    11 => NATIVE_PLACEMENT_LEFT_END,
+    _ => throw ArgumentError("Unknown value for native_placement_t: $value"),
+  };
+}
+
 /// @brief Application event types
 enum native_application_event_type_t {
   NATIVE_APPLICATION_EVENT_STARTED(0),

packages/cnativeapi/src/libnativeapi

@@ -1 +1,87 @@
 export 'dart:ui' show Offset, Size, Rect;
+
+import 'package:cnativeapi/cnativeapi.dart' show native_placement_t;
+
+/// Placement options for positioning UI elements relative to an anchor.
+///
+/// Placement defines how a UI element (such as a menu or popover) should be
+/// positioned relative to a reference point or rectangle.
+///
+/// Example:
+/// ```dart
+/// // Position menu below the anchor, horizontally centered
+/// menu.open(strategy, Placement.bottom);
+///
+/// // Position menu below the anchor, aligned to the left
+/// menu.open(strategy, Placement.bottomStart);
+///
+/// // Position menu above the anchor, aligned to the right
+/// menu.open(strategy, Placement.topEnd);
+/// ```
+enum Placement {
+  /// Position above the anchor, horizontally centered.
+  top,
+
+  /// Position above the anchor, aligned to the start (left).
+  topStart,
+
+  /// Position above the anchor, aligned to the end (right).
+  topEnd,
+
+  /// Position to the right of the anchor, vertically centered.
+  right,
+
+  /// Position to the right of the anchor, aligned to the start (top).
+  rightStart,
+
+  /// Position to the right of the anchor, aligned to the end (bottom).
+  rightEnd,
+
+  /// Position below the anchor, horizontally centered.
+  bottom,
+
+  /// Position below the anchor, aligned to the start (left).
+  bottomStart,
+
+  /// Position below the anchor, aligned to the end (right).
+  bottomEnd,
+
+  /// Position to the left of the anchor, vertically centered.
+  left,
+
+  /// Position to the left of the anchor, aligned to the start (top).
+  leftStart,
+
+  /// Position to the left of the anchor, aligned to the end (bottom).
+  leftEnd;
+
+  /// Convert this Placement to a native placement enum value.
+  native_placement_t toNative() {
+    switch (this) {
+      case Placement.top:
+        return native_placement_t.NATIVE_PLACEMENT_TOP;
+      case Placement.topStart:
+        return native_placement_t.NATIVE_PLACEMENT_TOP_START;
+      case Placement.topEnd:
+        return native_placement_t.NATIVE_PLACEMENT_TOP_END;
+      case Placement.right:
+        return native_placement_t.NATIVE_PLACEMENT_RIGHT;
+      case Placement.rightStart:
+        return native_placement_t.NATIVE_PLACEMENT_RIGHT_START;
+      case Placement.rightEnd:
+        return native_placement_t.NATIVE_PLACEMENT_RIGHT_END;
+      case Placement.bottom:
+        return native_placement_t.NATIVE_PLACEMENT_BOTTOM;
+      case Placement.bottomStart:
+        return native_placement_t.NATIVE_PLACEMENT_BOTTOM_START;
+      case Placement.bottomEnd:
+        return native_placement_t.NATIVE_PLACEMENT_BOTTOM_END;
+      case Placement.left:
+        return native_placement_t.NATIVE_PLACEMENT_LEFT;
+      case Placement.leftStart:
+        return native_placement_t.NATIVE_PLACEMENT_LEFT_START;
+      case Placement.leftEnd:
+        return native_placement_t.NATIVE_PLACEMENT_LEFT_END;
+    }
+  }
+}

packages/nativeapi/lib/src/foundation/geometry.dart

@@ -338,13 +338,23 @@ class Menu
   /// // Open context menu relative to a button with offset
   /// final buttonRect = button.getBounds();
   /// menu.open(PositioningStrategy.relative(buttonRect, Offset(0, 10)));
+  ///
+  /// // Open context menu with custom placement
+  /// menu.open(strategy, Placement.topStart);
   /// ```
-  bool open(PositioningStrategy strategy) {
+  bool open(
+    PositioningStrategy strategy, [
+    Placement placement = Placement.bottomStart,
+  ]) {
     // Convert Dart strategy to native strategy
     final nativeStrategy = strategy.toNative();
 
-    // Open menu with native strategy
-    final result = bindings.native_menu_open(_nativeHandle, nativeStrategy);
+    // Open menu with native strategy and placement
+    final result = bindings.native_menu_open(
+      _nativeHandle,
+      nativeStrategy,
+      placement.toNative(),
+    );
 
     // Free the native strategy
     bindings.native_positioning_strategy_free(nativeStrategy);

packages/nativeapi/lib/src/menu.dart

@@ -26,8 +26,6 @@ class _ContextMenuRegionState extends State<ContextMenuRegion> {
       },
       onPointerUp: (event) {
         if (!_shouldReact) return;
-        print('object ${event.position}');
-
         widget.menu.open(
           PositioningStrategy.absolute(
             Offset(event.position.dx, event.position.dy),