disable galvo controls when the beam is disabled

src/main/java/org/micromanager/lightsheetmanager/LightSheetManagerPlugin.java

@@ -15,7 +15,7 @@ public class LightSheetManagerPlugin implements MenuPlugin, SciJavaPlugin {
     public static final String copyright = "Applied Scientific Instrumentation (ASI), 2022-2026";
     public static final String description = "A plugin to control various types of light sheet microscopes.";
     public static final String menuName = "Light Sheet Manager";
-    public static final String version = "0.8.15";
+    public static final String version = "0.8.16";
 
     private Studio studio_;
 

src/main/java/org/micromanager/lightsheetmanager/gui/tabs/NavigationTab.java

@@ -25,7 +25,8 @@ public NavigationPanel getNavigationPanel() {
 
     @Override
     public void selected() {
-
+        // the beam may have been turned on or off on another tab or by an acquisition
+        navigationPanel_.updateBeamState();
     }
 
     @Override

src/main/java/org/micromanager/lightsheetmanager/gui/tabs/navigation/ControlPanel.java

@@ -41,6 +41,8 @@ public String toString() {
         }
     }
 
+    private static final String BEAM_ENABLED = "BeamEnabled";
+
     private final CMMCore core_;
 
     // data
@@ -60,6 +62,9 @@ public String toString() {
     private Button btnMoveToZero_;
     private Button btnSetZero_;
 
+    // true for a galvo whose device can blank the beam
+    private final boolean hasBeam_;
+
     private final LightSheetManager model_;
 
     public ControlPanel(final LightSheetManager model, final String propertyName, final String deviceName, final DeviceType deviceType, final Axis axis, final Units units) {
@@ -70,8 +75,10 @@ public ControlPanel(final LightSheetManager model, final String propertyName, fi
         deviceType_ = Objects.requireNonNull(deviceType);
         axis_ = axis;
         units_ = units;
+        hasBeam_ = deviceType_ == DeviceType.GalvoDevice && hasBeamProperty();
         createUserInterface();
         createEventHandlers();
+        updateBeamState();
     }
 
     public String getPropertyName() {
@@ -464,4 +471,37 @@ public void update(String topic, Object value) {
                 lblPosition_.setText(String.format("%.3f %s", position, units_)));
     }
 
+    /**
+     * Enables the move controls of a galvo only while its beam is on.
+     */
+    public void updateBeamState() {
+        if (!hasBeam_) {
+            return;
+        }
+        final boolean isBeamOn = isBeamOn();
+        SwingUtilities.invokeLater(() -> {
+            txtAbsoluteMove_.setEnabled(isBeamOn);
+            btnRelMoveMinus_.setEnabled(isBeamOn);
+            btnRelMovePlus_.setEnabled(isBeamOn);
+            btnMoveToZero_.setEnabled(isBeamOn);
+        });
+    }
+
+    private boolean hasBeamProperty() {
+        try {
+            return core_.hasProperty(deviceName_, BEAM_ENABLED);
+        } catch (Exception e) {
+            return false;
+        }
+    }
+
+    // the device adapter answers from its own state, so this does not query the controller
+    private boolean isBeamOn() {
+        try {
+            return "Yes".equals(core_.getProperty(deviceName_, BEAM_ENABLED));
+        } catch (Exception e) {
+            return true; // a failed read should not lock the controls
+        }
+    }
+
 }

src/main/java/org/micromanager/lightsheetmanager/gui/tabs/navigation/NavigationPanel.java

@@ -266,4 +266,12 @@ private boolean containsDigit(final String str) {
         return containsDigit;
     }
 
+    /**
+     * Updates the controls that depend on the beam, which can be turned on and off elsewhere.
+     */
+    public void updateBeamState() {
+        for (ControlPanel controlPanel : controlPanels_) {
+            controlPanel.updateBeamState();
+        }
+    }
 }