Add fluent builders for more flexibly adding data to Shuffleboard (#1022)

wpilibc/src/main/native/include/frc/shuffleboard/ComplexWidget.h

@@ -0,0 +1,46 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2018 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <memory>
+
+#include <networktables/NetworkTable.h>
+#include <wpi/Twine.h>
+
+#include "frc/shuffleboard/ShuffleboardWidget.h"
+#include "frc/smartdashboard/SendableBuilder.h"
+#include "frc/smartdashboard/SendableBuilderImpl.h"
+
+namespace frc {
+
+class Sendable;
+class ShuffleboardContainer;
+
+/**
+ * A Shuffleboard widget that handles a {@link Sendable} object such as a speed
+ * controller or sensor.
+ */
+class ComplexWidget final : public ShuffleboardWidget<ComplexWidget> {
+ public:
+  ComplexWidget(ShuffleboardContainer& parent, const wpi::Twine& title,
+                Sendable& sendable);
+
+  void EnableIfActuator() override;
+
+  void DisableIfActuator() override;
+
+  void BuildInto(std::shared_ptr<nt::NetworkTable> parentTable,
+                 std::shared_ptr<nt::NetworkTable> metaTable) override;
+
+ private:
+  Sendable& m_sendable;
+  SendableBuilderImpl m_builder;
+  bool m_builderInit = false;
+};
+
+}  // namespace frc