When switching panels in a split pane using the keyboard, focus on the output web view if the input text area is hidden. Make synchronised scrolling relative to the maximum scroll distance, i.e. the content height minus the window height.

Author: fjwright

src/fjwright/runreduce/REDUCEPanel.java

@@ -43,7 +43,7 @@ public class REDUCEPanel extends BorderPane {
     @FXML
     private Label outputLabel, inputLabel;
     @FXML
-    private ToggleButton hideEditorToggleButton;
+    ToggleButton hideEditorToggleButton;
     @FXML
     Label activeLabel;
     @FXML
@@ -61,8 +61,8 @@ public class REDUCEPanel extends BorderPane {
 
     final WebEngine webEngine;
     HTMLDocument doc;
-    private HTMLElement html, head, inputPre;
-    HTMLElement body;
+    HTMLElement html, body;
+    private HTMLElement head, inputPre;
     private JSObject katex, katexMacros;
     JSObject window;
 

src/fjwright/runreduce/RunREDUCE.java

@@ -29,6 +29,7 @@
 import javafx.scene.text.Font;
 import javafx.stage.Screen;
 import javafx.stage.Stage;
+import netscape.javascript.JSObject;
 import org.w3c.dom.events.EventListener;
 import org.w3c.dom.events.EventTarget;
 
@@ -165,14 +166,24 @@ private static void splitPaneKeyPressed(KeyEvent event) {
             reducePanel2 = tmp;
             reducePanel.setSelected(true); // new panel
             reducePanel.updateMenus();
-            reducePanel.inputTextArea.requestFocus();
+            if (reducePanel.hideEditorToggleButton.isSelected())
+                reducePanel.outputWebView.requestFocus();
+            else
+                reducePanel.inputTextArea.requestFocus();
         }
     }
 
     static final EventListener scrollListener = new EventListener() {
         public void handleEvent(org.w3c.dom.events.Event ev) {
-            int scrollY = (int) reducePanel.window.getMember("scrollY");
-            reducePanel2.window.call("scrollTo", 0, scrollY);
+//            int scrollY = (int) reducePanel.window.getMember("scrollY");
+//            reducePanel2.window.call("scrollTo", 0, scrollY);
+            // Relative scrolling:
+            int windowHeight = (int) reducePanel.window.getMember("innerHeight");
+            float thisScrollYMax = (int) ((JSObject) reducePanel.html).getMember("scrollHeight") - windowHeight;
+            float thatScrollYMax = (int) ((JSObject) reducePanel2.html).getMember("scrollHeight") - windowHeight;
+            int thisScrollY = (int) reducePanel.window.getMember("scrollY");
+            int thatScrollY = (int) (thisScrollY / thisScrollYMax * thatScrollYMax);
+            reducePanel2.window.call("scrollTo", 0, thatScrollY);
         }
     };