[wpilib] Add BooleanEvent/Trigger factories on HID classes (#4247)

wpilibNewCommands/src/main/native/include/frc2/command/button/CommandJoystick.h

@@ -0,0 +1,58 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#pragma once
+#include <frc/Joystick.h>
+
+#include "Trigger.h"
+#include "frc2/command/CommandScheduler.h"
+
+namespace frc2 {
+/**
+ * A subclass of {@link Joystick} with {@link Trigger} factories for
+ * command-based.
+ *
+ * @see Joystick
+ */
+class CommandJoystick : public frc::Joystick {
+ public:
+  using Joystick::Joystick;
+
+  /**
+   * Constructs an event instance around this button's digital signal.
+   *
+   * @param button the button index
+   * @param loop the event loop instance to attach the event to. Defaults to the
+   * CommandScheduler's default loop.
+   * @return an event instance representing the button's digital signal attached
+   * to the given loop.
+   */
+  class Trigger Button(
+      int button, frc::EventLoop* loop = CommandScheduler::GetInstance()
+                                             .GetDefaultButtonLoop()) const;
+
+  /**
+   * Constructs an event instance around the trigger button's digital signal.
+   *
+   * @param loop the event loop instance to attach the event to. Defaults to the
+   * CommandScheduler's default loop.
+   * @return an event instance representing the trigger button's digital signal
+   * attached to the given loop.
+   */
+  class Trigger Trigger(
+      frc::EventLoop* loop =
+          CommandScheduler::GetInstance().GetDefaultButtonLoop()) const;
+
+  /**
+   * Constructs an event instance around the top button's digital signal.
+   *
+   * @param loop the event loop instance to attach the event to. Defaults to the
+   * CommandScheduler's default loop.
+   * @return an event instance representing the top button's digital signal
+   * attached to the given loop.
+   */
+  class Trigger Top(frc::EventLoop* loop = CommandScheduler::GetInstance()
+                                               .GetDefaultButtonLoop()) const;
+};
+}  // namespace frc2