| KXL_EVENT_KEY_PRESS_MASK | When a key is press. |
| KXL_EVENT_KEY_RELEASE_MASK | When a key is release. |
| KXL_EVENT_BUTTON_PRESS_MASK | When a mouse button is press. |
| KXL_EVENT_BUTTON_RELEASE_MASK | When a mouse button is release. |
| KXL_EVENT_BUTTON_MOTION_MASK | When a moves pressing mouse button. |
| KXL_EVENT_EXPOSURE_MASK | When a demand of re-drawing. |