Synthesize and send events

Before you synthesize and send custom events, understand how the UI Toolkit event system allocates and sends operating system events.

The event system uses a pool of events to avoid allocating event objects repeatedly. To synthesize and send your own events:

1. イベントのプールからイベントオブジェクトを取得します。
2. イベントプロパティを入力します。
3. イベントを using ブロックで囲み、イベントプールに確実に返却されるようにします。
4. Pass the event to panel.visualTree.SendEvent().

You can send operating system events, such as keyboard and mouse events. To do so, use a UnityEngine.Event to initialize the UI Toolkit event.

次の例は、イベントを統合して送信する方法を示しています。

void SynthesizeAndSendKeyDownEvent(IPanel panel, KeyCode code,
     char character = '\0', EventModifiers modifiers = EventModifiers.None)
{
    // Create a UnityEngine.Event to hold initialization data.
    var evt = new Event() {
        type = EventType.KeyDownEvent,
        keyCode = code,
        character = character,
        modifiers = modifiers
    };

    using (KeyDownEvent keyDownEvent = KeyDownEvent.GetPooled(evt))
    {
        panel.visualTree.SendEvent(keyDownEvent);
    }
}

Note: Don’t send events that don’t come from the operating system and can’t be found in the UnityEngine.Event types. Some events are sent by UI Toolkit as a reaction to internal state changes and must not be sent by external processes. For example, if you send PointerCaptureEvent, visual elements assume that the underlying conditions for that event are met and won’t set pointer capture for them. This might break the internal configurations of the visual element and cause undefined behaviors.

その他の参考資料

• Dispatch events
• Handle events
• Events reference