[wpilib] Add robot callback that is called when the DS is initially connected (#5231)

wpilibc/src/main/native/cpp/IterativeRobotBase.cpp

@@ -24,6 +24,8 @@ IterativeRobotBase::IterativeRobotBase(units::second_t period)
 
 void IterativeRobotBase::RobotInit() {}
 
+void IterativeRobotBase::DriverStationConnected() {}
+
 void IterativeRobotBase::SimulationInit() {}
 
 void IterativeRobotBase::DisabledInit() {}
@@ -127,6 +129,11 @@ void IterativeRobotBase::LoopFunc() {
     mode = Mode::kTest;
   }
 
+  if (!m_calledDsConnected && word.IsDSAttached()) {
+    m_calledDsConnected = true;
+    DriverStationConnected();
+  }
+
   // If mode changed, call mode exit and entry functions
   if (m_lastMode != mode) {
     // Call last mode's exit function

wpilibc/src/main/native/include/frc/IterativeRobotBase.h

@@ -23,6 +23,9 @@ namespace frc {
  *
  * RobotInit() -- provide for initialization at robot power-on
  *
+ * DriverStationConnected() -- provide for initialization the first time the DS
+ * is connected
+ *
  * Init() functions -- each of the following functions is called once when the
  * appropriate mode is entered:
  *
@@ -67,6 +70,14 @@ class IterativeRobotBase : public RobotBase {
    */
   virtual void RobotInit();
 
+  /**
+   * Code that needs to know the DS state should go here.
+   *
+   * Users should override this method for initialization that needs to occur
+   * after the DS is connected, such as needing the alliance information.
+   */
+  virtual void DriverStationConnected();
+
   /**
    * Robot-wide simulation initialization code should go here.
    *
@@ -242,6 +253,7 @@ class IterativeRobotBase : public RobotBase {
   Watchdog m_watchdog;
   bool m_ntFlushEnabled = true;
   bool m_lwEnabledInTest = true;
+  bool m_calledDsConnected = false;
 
   void PrintLoopOverrunMessage();
 };

wpilibj/src/main/java/edu/wpi/first/wpilibj/IterativeRobotBase.java

@@ -24,6 +24,8 @@ import java.util.ConcurrentModificationException;
  *
  * <p>robotInit() -- provide for initialization at robot power-on
  *
+ * <p>driverStationConnected() -- provide for initialization the first time the DS is connected
+ *
  * <p>init() functions -- each of the following functions is called once when the appropriate mode
  * is entered:
  *
@@ -69,6 +71,7 @@ public abstract class IterativeRobotBase extends RobotBase {
   private final Watchdog m_watchdog;
   private boolean m_ntFlushEnabled = true;
   private boolean m_lwEnabledInTest = true;
+  private boolean m_calledDsConnected;
 
   /**
    * Constructor for IterativeRobotBase.
@@ -98,6 +101,14 @@ public abstract class IterativeRobotBase extends RobotBase {
    */
   public void robotInit() {}
 
+  /**
+   * Code that needs to know the DS state should go here.
+   *
+   * <p>Users should override this method for initialization that needs to occur after the DS is
+   * connected, such as needing the alliance information.
+   */
+  public void driverStationConnected() {}
+
   /**
    * Robot-wide simulation initialization code should go here.
    *
@@ -295,6 +306,11 @@ public abstract class IterativeRobotBase extends RobotBase {
       mode = Mode.kTest;
     }
 
+    if (!m_calledDsConnected && m_word.isDSAttached()) {
+      m_calledDsConnected = true;
+      driverStationConnected();
+    }
+
     // If mode changed, call mode exit and entry functions
     if (m_lastMode != mode) {
       // Call last mode's exit function