Enhancements to CodeArea and JavaKeywordsDemo

richtextfx-demos/src/main/java/org/fxmisc/richtext/demo/JavaKeywordsDemo.java

@@ -7,7 +7,10 @@
 import java.util.regex.Pattern;
 
 import javafx.application.Application;
+import javafx.application.Platform;
 import javafx.scene.Scene;
+import javafx.scene.input.KeyCode;
+import javafx.scene.input.KeyEvent;
 import javafx.scene.layout.StackPane;
 import javafx.stage.Stage;
 
@@ -103,6 +106,20 @@ public void start(Stage primaryStage) {
         // when no longer need syntax highlighting and wish to clean up memory leaks
         // run: `cleanupWhenNoLongerNeedIt.unsubscribe();`
 
+
+        // auto-indent: insert previous line's indents on enter
+        final Pattern whiteSpace = Pattern.compile( "^\\s+" );
+        codeArea.addEventHandler( KeyEvent.KEY_PRESSED, KE ->
+        {
+            if ( KE.getCode() == KeyCode.ENTER ) {
+            	int caretPosition = codeArea.getCaretPosition();
+            	int currentParagraph = codeArea.getCurrentParagraph();
+                Matcher m0 = whiteSpace.matcher( codeArea.getParagraph( currentParagraph-1 ).getSegments().get( 0 ) );
+                if ( m0.find() ) Platform.runLater( () -> codeArea.insertText( caretPosition, m0.group() ) );
+            }
+        });
+
+
         codeArea.replaceText(0, 0, sampleCode);
 
         Scene scene = new Scene(new StackPane(new VirtualizedScrollPane<>(codeArea)), 600, 400);

richtextfx/src/main/java/org/fxmisc/richtext/CodeArea.java

@@ -1,6 +1,6 @@
 package org.fxmisc.richtext;
 
-
+import java.text.BreakIterator;
 import java.util.Collection;
 
 import javafx.beans.NamedArg;
@@ -21,7 +21,7 @@ public class CodeArea extends StyleClassedTextArea {
         // don't apply preceding style to typed text
         setUseInitialStyleForInsertion(true);
     }
-
+    
     /**
      * Creates an area that can render and edit the same {@link EditableStyledDocument} as another {@link CodeArea}.
      */
@@ -52,4 +52,50 @@ public CodeArea(@NamedArg("text") String text) {
         // position the caret at the beginning
         selectRange(0, 0);
     }
+
+    @Override // to select words containing underscores
+    public void selectWord()
+    {
+        if ( getLength() == 0 ) return;
+
+        CaretSelectionBind<?,?,?> csb = getCaretSelectionBind();
+        int paragraph = csb.getParagraphIndex();
+        int position = csb.getColumnPosition(); 
+
+        String paragraphText = getText( paragraph );
+        BreakIterator breakIterator = BreakIterator.getWordInstance();
+        breakIterator.setText( paragraphText );
+
+        breakIterator.preceding( position );
+        int start = breakIterator.current();
+
+        while ( start > 0 && paragraphText.charAt( start-1 ) == '_' )
+        {
+            if ( --start > 0 && ! breakIterator.isBoundary( start-1 ) )
+            {
+                breakIterator.preceding( start );
+                start = breakIterator.current();
+            }
+        }
+
+        breakIterator.following( position );
+        int end = breakIterator.current();
+        int len = paragraphText.length();
+
+        while ( end < len && paragraphText.charAt( end ) == '_' )
+        {
+            if ( ++end < len && ! breakIterator.isBoundary( end+1 ) )
+            {
+                breakIterator.following( end );
+                end = breakIterator.current();
+            }
+            // For some reason single digits aren't picked up so ....
+            else if ( Character.isDigit( paragraphText.charAt( end ) ) )
+            {
+                end++;
+            }
+        }
+
+        csb.selectRange( paragraph, start, paragraph, end );
+    }
 }