AppFlowy/frontend/app_flowy/packages/appflowy_popover/README.md

AppFlowy Popover

A Popover can be used to display some content on top of another.

It can be used to display a dropdown menu.

A popover is a transient view that appears above other content onscreen when you tap a control or in an area. Typically, a popover includes an arrow pointing to the location from which it emerged. Popovers can be nonmodal or modal. A nonmodal popover is dismissed by tapping another part of the screen or a button on the popover. A modal popover is dismissed by tapping a Cancel or other button on the popover.

Source: Human Interface Guidelines.

Features

• Basic popover style
• Follow the target automatically
• Nested popover support
• Exclusive API

Example

Popover(
  // Define how to trigger the popover
  triggerActions: PopoverTriggerActionFlags.click,
  child: TextButton(child: Text("Popover"), onPressed: () {}),
  // Define the direction of the popover
  direction: PopoverDirection.bottomWithLeftAligned,
  popupBuilder(BuildContext context) {
    return PopoverMenu();
  },
);

Trigger the popover manually

Sometimes, if you want to trigger the popover manually, you can use a PopoverController.

class MyWidgetState extends State<GridDateCell> {
  late PopoverController _popover;

  @override
  void initState() {
    _popover = PopoverController();
    super.initState();
  }

  // triggered by another widget
  _onClick() {
    _popover.show();
  }

  @override
  Widget build(BuildContext context) {
    return Popover(
      controller: _popover,
      ...
    )
  }
}

Make several popovers exclusive

The popover has a mechanism to make sure there are only one popover is shown in a group of popovers. It's called PopoverMutex.

If you pass the same mutex object to the popovers, there will be only one popover is triggered.

class MyWidgetState extends State<GridDateCell> {
  final _popoverMutex = PopoverMutex();

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Popover(
          mutex: _popoverMutex,
          ...
        ),
        Popover(
          mutex: _popoverMutex,
          ...
        ),
        Popover(
          mutex: _popoverMutex,
          ...
        ),
      ]
    )
  }
}

API

Param	Description	Type
offset	The offset between the popover and the child	Offset
popupBuilder	The function used to build the popover	Widget Function(BuildContext context)
triggerActions	Define the actions about how to trigger the popover	int
mutex	If multiple popovers are exclusive, pass the same mutex to them.	PopoverMutex
direction	The direction where the popover should be placed	PopoverDirection
onClose	The callback will be called after the popover is closed	void Function()
child	The child to trigger the popover	Widget