edu.wpi.first.wpilibj.buttons

Class Trigger

java.lang.Object

edu.wpi.first.wpilibj.buttons.Trigger

All Implemented Interfaces:

Sendable

Direct Known Subclasses:

Button

public abstract class Trigger
extends java.lang.Object
implements Sendable

This class provides an easy way to link commands to inputs.

It is very easy to link a button to a command. For instance, you could link the trigger button of a joystick to a "score" command.

It is encouraged that teams write a subclass of Trigger if they want to have something unusual (for instance, if they want to react to the user holding a button while the robot is reading a certain sensor input). For this, they only have to write the get() method to get the full functionality of the Trigger class.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	Trigger.ButtonScheduler An internal class of Trigger.

Constructor Summary

Constructors

Constructor and Description
Trigger()

Method Summary

Modifier and Type	Method and Description
void	cancelWhenActive(Command command) Cancels a command when the trigger becomes active.
abstract boolean	get() Returns whether or not the trigger is active.
java.lang.String	getSmartDashboardType() These methods continue to return the "Button" SmartDashboard type until we decided to create a Trigger widget type for the dashboard.
ITable	getTable() The table that is associated with this Sendable.
void	initTable(ITable table) Initializes a table for this Sendable object.
void	toggleWhenActive(Command command) Toggles a command when the trigger becomes active.
void	whenActive(Command command) Starts the given command whenever the trigger just becomes active.
void	whenInactive(Command command) Starts the command when the trigger becomes inactive.
void	whileActive(Command command) Constantly starts the given command while the button is held.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Trigger

public Trigger()

Method Detail

get

public abstract boolean get()

Returns whether or not the trigger is active.

This method will be called repeatedly a command is linked to the Trigger.

Returns:

whether or not the trigger condition is active.

whenActive

public void whenActive(Command command)

Starts the given command whenever the trigger just becomes active.

Parameters:

command - the command to start

whileActive

public void whileActive(Command command)

Constantly starts the given command while the button is held. Command.start() will be called repeatedly while the trigger is active, and will be canceled when the trigger becomes inactive.

Parameters:

command - the command to start

whenInactive

public void whenInactive(Command command)

Starts the command when the trigger becomes inactive.

Parameters:

command - the command to start

toggleWhenActive

public void toggleWhenActive(Command command)

Toggles a command when the trigger becomes active.

Parameters:

command - the command to toggle

cancelWhenActive

public void cancelWhenActive(Command command)

Cancels a command when the trigger becomes active.

Parameters:

command - the command to cancel

getSmartDashboardType

public java.lang.String getSmartDashboardType()

These methods continue to return the "Button" SmartDashboard type until we decided to create a Trigger widget type for the dashboard.

Specified by:

getSmartDashboardType in interface Sendable

Returns:

The type of this Sendable.

initTable

public void initTable(ITable table)

Description copied from interface: Sendable

Initializes a table for this Sendable object.

Specified by:

initTable in interface Sendable

Parameters:

table - The table to put the values in.

getTable

public ITable getTable()

Description copied from interface: Sendable

The table that is associated with this Sendable.

Specified by:

getTable in interface Sendable

Returns:

the table that is currently associated with the Sendable.