Improve preferences grid layout (#28)

nrgcommon/src/main/java/com/nrg948/annotations/Annotations.java

@@ -106,7 +106,6 @@ private static Optional<Reflections> loadFromMetadata() {
       }
     } catch (Exception e) {
       System.err.println("WARNING: Failed to load Reflections metadata: " + e.getMessage());
-      reflections = null;
     }
 
     return reflections;

nrgcommon/src/main/java/com/nrg948/package-info.java

@@ -27,7 +27,7 @@ of this software and associated documentation files (the "Software"), to deal
  * used by FIRST Robotics Competition Team 948 - Newport Robotics Group (NRG948).
  * 
  * <p>
- * To initialize the libray, you must call the {@link Common#init(String...)}
+ * To initialize the library, you must call the {@link Common#init(String...)}
  * method passing the name of the robot package. In the Command-based Robot,
  * this must be done in the <code>Robot.initRobot()</code> method before the
  * <code>RobotContainer</code> is created.<br>

nrgcommon/src/main/java/com/nrg948/preferences/RobotPreferences.java

@@ -30,10 +30,14 @@ of this software and associated documentation files (the "Software"), to deal
 import java.lang.reflect.Field;
 import java.lang.reflect.Modifier;
 import java.util.EnumSet;
+import java.util.Map;
 import java.util.Set;
+import java.util.concurrent.CountDownLatch;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import org.javatuples.Pair;
+
 import com.nrg948.annotations.Annotations;
 
 import edu.wpi.first.networktables.BooleanTopic;
@@ -44,8 +48,11 @@ of this software and associated documentation files (the "Software"), to deal
 import edu.wpi.first.networktables.NetworkTableInstance;
 import edu.wpi.first.networktables.StringTopic;
 import edu.wpi.first.wpilibj.Preferences;
+import edu.wpi.first.wpilibj.shuffleboard.BuiltInLayouts;
 import edu.wpi.first.wpilibj.shuffleboard.BuiltInWidgets;
+import edu.wpi.first.wpilibj.shuffleboard.ComplexWidget;
 import edu.wpi.first.wpilibj.shuffleboard.Shuffleboard;
+import edu.wpi.first.wpilibj.shuffleboard.ShuffleboardComponent;
 import edu.wpi.first.wpilibj.shuffleboard.ShuffleboardLayout;
 import edu.wpi.first.wpilibj.shuffleboard.ShuffleboardTab;
 import edu.wpi.first.wpilibj.shuffleboard.SimpleWidget;
@@ -463,14 +470,28 @@ public <E extends Enum<E>> void visit(EnumValue<E> value) {
   private static class ShuffleboardWidgetBuilder implements IValueVisitor {
 
     private ShuffleboardLayout layout;
+    private RobotPreferencesValue metadata;
 
-    public ShuffleboardWidgetBuilder(ShuffleboardLayout layout) {
+    /**
+     * Constructs a visitor that creates Shuffleboard widgets for preference
+     * values.
+     * 
+     * @param layout   The Shuffleboard layout to add a widget for the visited
+     *                 value.
+     * @param metadata A {@link RobotPreferencesValue} annotation containing the
+     *                 value's metadata.
+     */
+    public ShuffleboardWidgetBuilder(ShuffleboardLayout layout, RobotPreferencesValue metadata) {
       this.layout = layout;
+      this.metadata = metadata;
     }
 
     @Override
     public void visit(StringValue value) {
       SimpleWidget widget = layout.add(value.getName(), value.getValue()).withWidget(BuiltInWidgets.kTextView);
+
+      configureWidget(widget);
+
       GenericEntry entry = widget.getEntry();
 
       entry.setString(value.getValue());
@@ -488,6 +509,9 @@ public void visit(StringValue value) {
     public void visit(BooleanValue value) {
       SimpleWidget widget = layout.add(value.getName(), value.getValue())
           .withWidget(BuiltInWidgets.kToggleSwitch);
+
+      configureWidget(widget);
+
       GenericEntry entry = widget.getEntry();
 
       entry.setBoolean(value.getValue());
@@ -504,6 +528,9 @@ public void visit(BooleanValue value) {
     @Override
     public void visit(DoubleValue value) {
       SimpleWidget widget = layout.add(value.getName(), value.getValue()).withWidget(BuiltInWidgets.kTextView);
+
+      configureWidget(widget);
+
       GenericEntry entry = widget.getEntry();
 
       entry.setDouble(value.getValue());
@@ -527,7 +554,9 @@ public <E extends Enum<E>> void visit(EnumValue<E> value) {
           .forEach(e -> chooser.addOption(e.toString(), e));
       chooser.setDefaultOption(currentValue.toString(), currentValue);
 
-      layout.add(value.getName(), chooser);
+      ComplexWidget widget = layout.add(value.getName(), chooser);
+
+      configureWidget(widget);
 
       NetworkTableInstance ntInstance = NetworkTableInstance.getDefault();
       NetworkTableEntry chooserEntry = ntInstance
@@ -543,6 +572,28 @@ public <E extends Enum<E>> void visit(EnumValue<E> value) {
           (event) -> value.setValue(event.valueData.value.getString()));
     }
 
+    /**
+     * Configures the visited value's widget according to the metadata information.
+     * 
+     * @param widget The Shuffleboard widget to configure.
+     */
+    private void configureWidget(ShuffleboardComponent<?> widget) {
+      if (layout.getType().equals(BuiltInLayouts.kGrid.getLayoutName())) {
+        int column = metadata.column();
+        int row = metadata.row();
+
+        if (column >= 0 && row >= 0) {
+          widget.withPosition(column, row);
+        }
+
+        int width = metadata.width();
+        int height = metadata.height();
+
+        if (width > 0 && height > 0) {
+          widget.withSize(width, height);
+        }
+      }
+    }
   }
 
   /** The name of the Shuffleboard tab containing the preferences widgets. */
@@ -581,16 +632,34 @@ public static void addShuffleBoardTab() {
             .asClass());
 
     classes.stream().map(c -> c.getAnnotation(RobotPreferencesLayout.class)).forEach(layout -> {
-      prefsTab.getLayout(layout.groupName(), layout.type())
+      var shuffleboardLayout = prefsTab.getLayout(layout.groupName(), layout.type())
           .withPosition(layout.column(), layout.row())
           .withSize(layout.width(), layout.height());
-    });
 
-    getAllValues().collect(Collectors.groupingBy(Value::getGroup)).forEach((group, values) -> {
-      ShuffleboardLayout layout = prefsTab.getLayout(group);
-      ShuffleboardWidgetBuilder builder = new ShuffleboardWidgetBuilder(layout);
-      values.stream().forEach((value) -> value.accept(builder));
+      if (layout.type().equals(BuiltInLayouts.kGrid.getLayoutName())) {
+        int gridColumns = layout.gridColumns();
+        int gridRows = layout.gridRows();
+
+        if (gridColumns > 0 && gridRows > 0) {
+          shuffleboardLayout
+              .withProperties(Map.of("Number of columns", gridColumns, "Number of rows", gridRows));
+        }
+      }
     });
+
+    getFields()
+        .map(RobotPreferences::mapToPair)
+        .collect(Collectors.groupingBy(p -> p.getValue1().group))
+        .forEach((group, pairs) -> {
+          ShuffleboardLayout layout = prefsTab.getLayout(group);
+
+          pairs.stream()
+              .forEach(pair -> {
+                ShuffleboardWidgetBuilder builder = new ShuffleboardWidgetBuilder(layout, pair.getValue0());
+
+                pair.getValue1().accept(builder);
+              });
+        });
   }
 
   /** Returns a stream of fields containing preferences values. */
@@ -616,6 +685,11 @@ private static Value mapToValue(Field field) {
     return null;
   }
 
+  /** Maps a preferences field to a pair of its annotation and value instance */
+  private static Pair<RobotPreferencesValue, Value> mapToPair(Field field) {
+    return Pair.with(field.getAnnotation(RobotPreferencesValue.class), mapToValue(field));
+  }
+
   /** Returns all preferences values. */
   private static Stream<Value> getAllValues() {
     return getFields().map(RobotPreferences::mapToValue).filter(v -> v != null);

nrgcommon/src/main/java/com/nrg948/preferences/RobotPreferencesLayout.java

@@ -82,4 +82,20 @@ of this software and associated documentation files (the "Software"), to deal
    * @return The layout type.
    */
   String type() default "List Layout";
+
+  /**
+   * The number of columns in a grid layout. This value is ignored if the
+   * {@link RobotPreferencesLayout#type} is "List Layout".
+   * 
+   * @return The number of columns.
+   */
+  int gridColumns() default -1;
+
+  /**
+   * The number of rows in a grid layout. This value is ignored if the
+   * {@link RobotPreferencesLayout#type} is "List Layout".
+   * 
+   * @return The number of rows.
+   */
+  int gridRows() default -1;
 }

nrgcommon/src/main/java/com/nrg948/preferences/RobotPreferencesValue.java

@@ -33,5 +33,35 @@ of this software and associated documentation files (the "Software"), to deal
 @Target(ElementType.FIELD)
 @Retention(RetentionPolicy.RUNTIME)
 public @interface RobotPreferencesValue {
+  /**
+   * The column position in a grid layout. This value is ignored if the
+   * {@link RobotPreferencesLayout#type} of the value's group is "List Layout".
+   * 
+   * @return The column position of this value.
+   */
+  int column() default -1;
 
+  /**
+   * The row position in a grid layout. This value is ignored if the
+   * {@link RobotPreferencesLayout#type} of the value's group is "List Layout".
+   * 
+   * @return The row position of this value.
+   */
+  int row() default -1;
+
+  /**
+   * The width of this value in a grid layout. This value is ignored if the
+   * {@link RobotPreferencesLayout#type} of the value's group is "List Layout".
+   * 
+   * @return The width of this value.
+   */
+  int width() default -1;
+
+  /**
+   * The height of this value in a grid layout. This value is ignored if the
+   * {@link RobotPreferencesLayout#type} of the value's group is "List Layout".
+   * 
+   * @return The height of this value.
+   */
+  int height() default -1;
 }

nrgcommon/src/main/java/com/nrg948/preferences/package-info.java

@@ -33,7 +33,7 @@ of this software and associated documentation files (the "Software"), to deal
  * group of PID preferences to be added automatically to Shuffleboard.
  * 
  * <p>
- * The followng example defines the PID constants in a class derived from
+ * The following example defines the PID constants in a class derived from
  * {@link PIDSubsystem} and enables a layout to be generated for the
  * Shuffleboard.<br>
  *