Render line numbers using TextAreaPainter

Fix the line number font rendering problem on the Mac.

Now, the TextAreaLineNumbers class extends the TextAreaPainter and just
overloads the paintLine method to make it render the line number instead
of rendering the whole line. Other than that, the superclass' drawing
code is used.

So: the same drawing code that renders the source code text in the
editor is now also being used to render the line numbers.

Author: Cayci

app/src/processing/app/Editor.java

@@ -452,7 +452,6 @@ protected void applyPreferences() {
     // apply changes to the font size for the editor
     //TextAreaPainter painter = textarea.getPainter();
     painter.setFont(Preferences.getFont("editor.font"));
-    textarea.setLineNumbersFont(Preferences.getFont("editor.font"));
     //Font font = painter.getFont();
     //textarea.getPainter().setFont(new Font("Courier", Font.PLAIN, 36));
 

app/src/processing/app/syntax/JEditTextArea.java

@@ -87,7 +87,7 @@ public JEditTextArea(TextAreaDefaults defaults)
 
     // Initialize some misc. stuff
     painter = new TextAreaPainter(this,defaults);
-    editorLineNumbers = new TextAreaLineNumbers(defaults, (int) painter.getPreferredSize().getHeight());
+    editorLineNumbers = new TextAreaLineNumbers(this,defaults);
     documentHandler = new DocumentHandler();
     eventListenerList = new EventListenerList();
     caretEvent = new MutableCaretEvent();
@@ -321,8 +321,10 @@ public void updateScrollBars() {
   }
 
   private void updateLineNumbers() {
-    editorLineNumbers.updateLineNumbers(getFirstLine() + 1, Math.min(getFirstLine() + getVisibleLines() + 1, getLineCount()));
-    editorLineNumbers.updateWidthForNumDigits(String.valueOf(getLineCount()).length());
+    if (editorLineNumbers != null) {
+      editorLineNumbers.updateLineNumbers(getFirstLine() + 1, Math.min(getFirstLine() + getVisibleLines() + 1, getLineCount()));
+      editorLineNumbers.updateWidthForNumDigits(String.valueOf(getLineCount()).length());
+    }
   }
 
   /**
@@ -803,7 +805,11 @@ public final int getDocumentLength()
    */
   public final int getLineCount()
   {
-    return document.getDefaultRootElement().getElementCount();
+    if (document != null) {
+      return document.getDefaultRootElement().getElementCount();
+    } else {
+      return 0;
+    }
   }
 
   /**
@@ -2431,8 +2437,4 @@ public boolean addEdit(UndoableEdit edit)
   public void setDisplayLineNumbers(boolean displayLineNumbers) {
     editorLineNumbers.setDisplayLineNumbers(displayLineNumbers);
   }
-
-  public void setLineNumbersFont(Font font) {
-    editorLineNumbers.setTextFont(font);
-  }
 }

app/src/processing/app/syntax/TextAreaLineNumbers.java

@@ -10,19 +10,12 @@
 package processing.app.syntax;
 
 import java.awt.Color;
-import java.awt.Dimension;
-import java.awt.Font;
+import java.awt.Graphics;
 import java.awt.Rectangle;
 
-import javax.swing.JTextPane;
 import javax.swing.border.MatteBorder;
-import javax.swing.text.AttributeSet;
-import javax.swing.text.SimpleAttributeSet;
-import javax.swing.text.StyleConstants;
 
-import processing.app.Preferences;
-
-public class TextAreaLineNumbers extends JTextPane {
+public class TextAreaLineNumbers extends TextAreaPainter {
 
   private final int LEFT_INDENT = 6;
   private final int RIGHT_INDENT = 6;
@@ -37,29 +30,14 @@ public class TextAreaLineNumbers extends JTextPane {
   private int currEndNum = 0;
   private int currNumDigits = MIN_NUM_DIGITS;
 
-  public TextAreaLineNumbers(TextAreaDefaults defaults, int preferredHeight) {
-    setBackground(defaults.bgcolor);
-    setForeground(defaults.fgcolor);
-    setOpaque(true);
-    setEditable(false);
-    setEnabled(false);
-    setBorder(new MatteBorder(0, 0, 0, 1, new Color(240, 240, 240)));
-    setTextFont(Preferences.getFont("editor.font")); 
-    
+  
+  
+  public TextAreaLineNumbers(JEditTextArea textArea, TextAreaDefaults defaults) {
+    super(textArea, defaults);
     DIGIT_WIDTH = getFontMetrics(getFont()).stringWidth("0");
     MIN_WIDTH = DIGIT_WIDTH * MIN_NUM_DIGITS + PADDING_WIDTH;
-    
-    setPreferredSize(new Dimension(MIN_WIDTH, preferredHeight));
-  }
-
-  public void setTextFont(Font font) {
-    setFont(font);
-    SimpleAttributeSet attribs = new SimpleAttributeSet();  
-    StyleConstants.setAlignment(attribs , StyleConstants.ALIGN_RIGHT);
-    StyleConstants.setLeftIndent(attribs , 6);
-    StyleConstants.setRightIndent(attribs , 6);
-    StyleConstants.setFontSize(attribs, getFont().getSize());
-    setParagraphAttributes(attribs,true);
+    setEnabled(false);
+    setBorder(new MatteBorder(0, 0, 0, RIGHT_BORDER_WIDTH, new Color(240, 240, 240)));
   }
 
   public void updateLineNumbers(int startNum, int endNum) {
@@ -69,14 +47,30 @@ public void updateLineNumbers(int startNum, int endNum) {
     currStartNum = startNum;
     currEndNum = endNum;
 
-    StringBuilder sb = new StringBuilder();
-    for (int i = startNum; i < endNum; i++) {
-      sb.append(i).append("\n");
-    }
-    sb.append(endNum);
-    setText(sb.toString());
-
     invalidate();
+    repaint();
+  }
+  
+  @Override
+  public void paint(Graphics gfx) {
+    super.paint(gfx);
+    getBorder().paintBorder(this, gfx, 0, 0, getSize().width, getSize().height);
+  }
+
+  @Override
+  protected void paintLine(Graphics gfx, TokenMarker tokenMarker,
+                           int line, int x)
+  {
+    currentLineIndex = line;
+    gfx.setFont(getFont());
+    gfx.setColor(Color.GRAY);
+    int y = textArea.lineToY(line);
+    int startX = getBounds().x + getBounds().width;
+    if (line >= 0 && line < textArea.getLineCount()) {
+      String lineNumberString = String.valueOf(line+1);
+      int lineStartX = startX - RIGHT_BORDER_WIDTH - RIGHT_INDENT - fm.stringWidth(lineNumberString);
+      gfx.drawString(lineNumberString,lineStartX,y + fm.getHeight());
+    }
   }
 
   public void updateWidthForNumDigits(int numDigits) {
@@ -85,8 +79,11 @@ public void updateWidthForNumDigits(int numDigits) {
     }
     currNumDigits = numDigits;
 
-    updateBounds();
-    invalidate();
+    if (isVisible()) {
+      updateBounds();
+      invalidate();
+      repaint();
+    }
   }
 
   public void setDisplayLineNumbers(boolean displayLineNumbers) {
@@ -97,9 +94,13 @@ public void setDisplayLineNumbers(boolean displayLineNumbers) {
       setBounds(new Rectangle(0, getHeight()));
     }
     invalidate();
+    repaint();
   }
 
   private void updateBounds() {
-    setBounds(new Rectangle(Math.max(MIN_WIDTH, DIGIT_WIDTH * currNumDigits + PADDING_WIDTH), getHeight()));
+    if (isVisible()) {
+      setBounds(new Rectangle(Math.max(MIN_WIDTH, DIGIT_WIDTH * currNumDigits + PADDING_WIDTH), getHeight()));
+      textArea.validate();
+    }
   }
 }