UI Toolkit raises an event when a user interacts with and changes the state of elements from UI Toolkit. The event design is similar to the Event interface for HTML elements.
Event types fit into a hierarchy based on the EventBase class. Each event family implements an interface that defines the common characteristics of all events of the same family. For example, BlurEvent and FocusEvent use the FocusEventBase class.
选择下面列出的任何事件类型，以获取有关事件、其父类和 API 文档链接的更多信息。
| Topic | 描述 |
|---|---|
| Capture events | Events that capture the user’s interaction with the UI. |
| Change events | Events that occur when the user changes the state of an element. |
| Click events | Events that occur when the user clicks an element. |
| Command events | Events that occur when the user invokes a command. |
| Drag and drop events | Events that occur when the user drags and drops an element. |
| Layout events | Events that occur when the layout engine changes the layout of an element. |
| Focus events | Events that occur when the user focuses on an element. |
| Input events | Events that occur when the user inputs text. |
| Keyboard events | Events that occur when the user presses a key. |
| Mouse events | Events that occur when the user moves the mouse. |
| Navigation events | Events that occur when the user navigates through the UI. |
| Panel events | Events that occur when the user interacts with a panel. |
| Pointer events | Events that occur when the user interacts with a pointer device. |
| Tooltip events | Events that occur when the user interacts with a tooltip. |
| Transition events | Events that inform you of changes to the state of transition. |
| ContextualMenu events | Events that occur when the user interacts with a contextual menu. |
| IMGUI events | Events that occur when the user interacts with an IMGUI element. |