ui.properties

Interface Input

All Known Subinterfaces:

DrawUserInterface, OthelloUserInterface, SnakeUserInterface

public interface Input

Interfaces that implement this property provides the possibility to receive events. Events are necessary to make a program interactive. The events provide information to the user about the things taking place on the UserInterface.

Events are queued. Every call to the getEvent() function removes a single event from the queue. If the queue is empty, the program blocks until an event is raised. The table below shows all possible events:

MouseEvents

Name	Description	Data
mouseover	This event is generated when the mouse enters an object.	In the SnakeUserInterface and OthelloUserInterface The coordinate of the cell on which the mouse is located. For example "4 3" Note: The OthelloUserInterface has cells starting at 1, instead of 0. In the DrawUserInterface The name of the hotspot, which the mouse enters.
mouseexit	Only in DiagramTekenUserInterface When the mouse leaves a hotspot.	The name of the hotspot, which the mouse leaves.
click	When the user clicks on an object	In the SnakeUserInterface and OthelloUserInterface The coordinate of the cell on which the mouse is located. For example "4 3" Note: The OthelloUserInterface has cells starting at 1, instead of 0. In the DrawUserInterface The name of the hotspot on which the user clicked.

AlarmEvents

Name	Description	Data
alarm	When an alarm is generated by the AlarmSystem via the method AlarmSystem.setAlarm(String, int, boolean).	The name of the alarm, i.e. the string provided when calling AlarmSystem.setAlarm(String, int, boolean). When the alarm is raised to signal a screen refresh, i.e. generated by AnimationEventSystem.setFramesPerSecond(double), the data will be "refresh".

KeyboardEvents

Name	Description	Data
arrow	One of the arrow keys is pressed.	"L" for left, "R" for right, "U" for up, "D" for down.
number	One of the number keys is being pressed	The number that is being pressed.
alt_number	One of the number keys is being pressed, whilst the alt key is also being pressed.	The number that is being pressed.
letter	A letter is being pressed.	The letter, or capital letter, if shift or caps-lock are enabled.
other_key	A key is being pressed, which is not a number, letter or arrow,	A string describing the key, for example: "Slash", "Ctrl"

Method Summary

Modifier and Type	Method and Description
void	enableEventProcessing(boolean on) This method can enable or disable the reception of events.
Event	getEvent() This function blocks until an event occurs and returns an Event object with the name and the data of the event that occurred.

Method Detail

getEvent

Event getEvent()

This function blocks until an event occurs and returns an Event object with the name and the data of the event that occurred. For example, pressing the letter a will result in an event with the name "leter" and data "a".

enableEventProcessing

void enableEventProcessing(boolean on)

This method can enable or disable the reception of events. This may be usefull if the program is not going to be able to react to event for a long time. To ensure that a flood of events is prevented, the reception of events can be turned off. The reception of events is enables by default.

Parameters:

on - If true, events are received, if false, events are ignored.