Module conrod_core::event

Contains all types used to describe the input events that Widgets may handle.

The two primary types of this module are:

• Input: conrod's input type passed by the user to Ui::handle_event in order to drive the Ui.
• Event: enumerates all possible events interpreted by conrod that may be propagated to widgets.

The Event System

Conrod's event system looks like this:

Input -> Ui -> Event -> Widget

The Ui receives Inputs such as Press and Release via the Ui::handle_event method. It interprets these Inputs to create higher-level Events such as DoubleClick, WidgetCapturesKeyboard, etc. These Events are stored and then fed to each Widget when Ui::set_widgets is called. At the end of Ui::set_widgets the stored Events are flushed ready for the next incoming Inputs.

Conrod uses the pistoncore-input crate's Input type. There are a few reasons for this:

1. This Input type already provides a number of useful variants of events that we wish to provide and handle within conrod, and we do not yet see any great need to re-write it and duplicate code.
2. The Input type is already compatible with all pistoncore-window backends including glfw_window, sdl2_window and glutin_window. That said, co-ordinates and scroll directions may need to be translated to conrod's orientation.
3. The pistoncore-input crate also provides a GenericEvent trait which allows us to easily provide a blanket implementation of ToRawEvent for all event types that already implement this trait.

Because we use the pistoncore-input Event type, we also re-export its associated data types (Button, ControllerAxisArgs, Key, etc).

Structs

Click	Contains all the relevant information for a mouse click.
DoubleClick	Contains all the relevant information for a double click.
Drag	Contains all the relevant information for a mouse drag.
KeyPress	Contains all relevant information for the event where a keyboard button was pressed.
KeyRelease	Contains all relevant information for the event where a keyboard button was release.
Motion	Contains all relevant information for a Motion event.
MousePress	Contains all relevant information for the event where a mouse button was pressed.
MouseRelease	Contains all relevant information for the event where a mouse button was released.
Press	Contains all relevant information for a Press event.
Release	Contains all relevant information for a Release event.
Scroll	Holds all the relevant information about a scroll event
Tap	All relevant information for a touch-screen tap event.
Text	Contains all relevant information for a Text event.

Enums

Button	The different kinds of Buttons that may be Pressed or Released.
Event	Enum containing all the events that the Ui may provide.
Input	The event type that is used by conrod to track inputs from the world. Events yielded by polling window backends should be converted to this type. This can be thought of as the event type which is supplied by the window backend to drive the state of the Ui forward.
Ui	Represents all events interpreted by the Ui.
Widget	Events that apply to a specific widget.