Rounding for jTextArea

[ViktorTrojan]

Hey I wondered if you could add an option to round the jTextArea?

[DevCharly]

If the JTextArea is in a JScrollPane ?

[ViktorTrojan]

If the JTextArea is in a JScrollPane ?

It is but I dont know any way to round a JScrollPane

[mlaggner]

As far as I see this heavily depends whether you embed the JTextArea into a scrollbar or not.

If it is embedded, you need to put the FlatTextBorder on the JScrollPane (which results all scrollpanes to use this border - but in my tests, I did not see this border for JTables or JLists).

If it is not embedded, you need to put the FlatTextBorder on the JTextArea

At the moment I am unsure how to handle mixing this without using component properties...

[mlaggner]

looks like rounded JScrollPane contents are rather complicated, because the viewport draws the clipped part into the corners (at least this is what I found out while trying to implement that).

I hope @DevCharly has a better idea how to solve that

[mlaggner]

I found a workaround by creating a new component for a JTextArea (mostly by merging code from the UI for JTextArea and JTextField) which is not inside a JScrollPane:

public class RoundTextArea extends JTextArea {

  private static final String uiClassID = "RoundTextAreaUI";

  public TmmRoundTextArea() {
    super();
    setLineWrap(true);
    setWrapStyleWord(true);
  }

  public TmmRoundTextArea(String text) {
    super(text);
    setLineWrap(true);
    setWrapStyleWord(true);
  }

  /**
   * Returns the class ID for the UI.
   *
   * @return the string "TextAreaUI"
   * @see JComponent#getUIClassID
   * @see UIDefaults#getUI
   */
  @Override
  @BeanProperty(bound = false)
  public String getUIClassID() {
    return uiClassID;
  }
}

public class RoundTextAreaUI extends FlatTextAreaUI {

  private FocusListener focusListener;
  private DocumentListener documentListener;


  public static ComponentUI createUI(JComponent c) {
    return new TmmRoundTextAreaUI();
  }

  @Override
  protected void installDefaults() {
    super.installDefaults();

    LookAndFeel.installProperty(getComponent(), "opaque", false);
    getComponent().setBorder(new FlatTextBorder());
  }

  @Override
  protected void installListeners() {
    super.installListeners();

    // necessary to update focus border and background
    focusListener = new FlatUIUtils.RepaintFocusListener( getComponent(), null );
    getComponent().addFocusListener( focusListener );
  }

  @Override
  protected void uninstallListeners() {
    super.uninstallListeners();

    getComponent().removeFocusListener( focusListener );
    focusListener = null;

    if( documentListener != null ) {
      getComponent().getDocument().removeDocumentListener( documentListener );
      documentListener = null;
    }
  }

  @Override
  protected void paintSafely(Graphics g) {
    paintBackground(g, getComponent(), isIntelliJTheme, focusedBackground);
    super.paintSafely(g);
  }

  @Override
  protected void paintBackground(Graphics g) {
    // painted somehere else
  }

  static void paintBackground(Graphics g, JTextComponent c, boolean isIntelliJTheme, Color focusedBackground) {
    // do not paint background if:
    // - not opaque and
    // - border is not a flat border and
    // - opaque was explicitly set (to false)
    // (same behavior as in AquaTextFieldUI)
    if (!c.isOpaque() && FlatUIUtils.getOutsideFlatBorder(c) == null && FlatUIUtils.hasOpaqueBeenExplicitlySet(c)) {
      return;
    }

    float focusWidth = FlatUIUtils.getBorderFocusWidth(c);
    float arc = FlatUIUtils.getBorderArc(c);

    // fill background if opaque to avoid garbage if user sets opaque to true
    if (c.isOpaque() && (focusWidth > 0 || arc > 0)) {
      FlatUIUtils.paintParentBackground(g, c);
    }

    // paint background
    Graphics2D g2 = (Graphics2D) g.create();
    try {
      FlatUIUtils.setRenderingHints(g2);

      g2.setColor(getBackground(c, isIntelliJTheme, focusedBackground));
      FlatUIUtils.paintComponentBackground(g2, 0, 0, c.getWidth(), c.getHeight(), focusWidth, arc);
    }
    finally {
      g2.dispose();
    }
  }

  private static Color getBackground(JTextComponent c, boolean isIntelliJTheme, Color focusedBackground) {
    Color background = c.getBackground();

    // always use explicitly set color
    if (!(background instanceof UIResource)) {
      return background;
    }

    // focused
    if (focusedBackground != null && FlatUIUtils.isPermanentFocusOwner(c)) {
      return focusedBackground;
    }

    // for compatibility with IntelliJ themes
    if (isIntelliJTheme && (!c.isEnabled() || !c.isEditable())) {
      return FlatUIUtils.getParentBackground(c);
    }

    return background;
  }
}

and register that to FlatLaf:

RoundTextAreaUI=x.y.z.RoundTextAreaUI

I know this is rather hacky, but at least that works for my use case

[DevCharly]

There is now a draft PR for rounded scrollpanes. See PR #713.

[mlaggner]

looks promising. When will this be available in the FlatLaf release?

[DevCharly]

implemented in latest 3.3-SNAPSHOT: https://github.com/JFormDesigner/FlatLaf#snapshots