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

wpilibc/src/main/native/cpp/shuffleboard/ComplexWidget.cpp

@@ -0,0 +1,42 @@
+/*----------------------------------------------------------------------------*/
+/* 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.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "frc/shuffleboard/ComplexWidget.h"
+
+#include "frc/smartdashboard/Sendable.h"
+
+using namespace frc;
+
+ComplexWidget::ComplexWidget(ShuffleboardContainer& parent,
+                             const wpi::Twine& title, Sendable& sendable)
+    : ShuffleboardValue(title),
+      ShuffleboardWidget(parent, title),
+      m_sendable(sendable) {}
+
+void ComplexWidget::EnableIfActuator() {
+  if (m_builder.IsActuator()) {
+    m_builder.StartLiveWindowMode();
+  }
+}
+
+void ComplexWidget::DisableIfActuator() {
+  if (m_builder.IsActuator()) {
+    m_builder.StopLiveWindowMode();
+  }
+}
+
+void ComplexWidget::BuildInto(std::shared_ptr<nt::NetworkTable> parentTable,
+                              std::shared_ptr<nt::NetworkTable> metaTable) {
+  BuildMetadata(metaTable);
+  if (!m_builderInit) {
+    m_builder.SetTable(parentTable->GetSubTable(GetTitle()));
+    m_sendable.InitSendable(m_builder);
+    m_builder.StartListeners();
+    m_builderInit = true;
+  }
+  m_builder.UpdateTable();
+}