Class RTextAreaUI

All Implemented Interfaces:
ViewFactory
Direct Known Subclasses:
RSyntaxTextAreaUI

public class RTextAreaUI extends BasicTextAreaUI
The UI used by instances of RTextArea. This UI takes into account all the "extras" involved in an RTextArea, including having a special caret (for insert and overwrite), background images, highlighting the current line, etc.
Version:
0.5
  • Field Details

  • Constructor Details

    • RTextAreaUI

      public RTextAreaUI(JComponent textArea)
      Constructor.
      Parameters:
      textArea - An instance of RTextArea.
      Throws:
      IllegalArgumentException - If textArea is not an instance of RTextArea.
  • Method Details

    • createUI

      public static ComponentUI createUI(JComponent textArea)
      Creates a UI for an RTextArea.
      Parameters:
      textArea - A text area.
      Returns:
      The UI.
    • correctNimbusDefaultProblems

      private void correctNimbusDefaultProblems(JTextComponent editor)
      The Nimbus LAF (and any Synth laf might have similar issues) doesn't set many UIManager properties that BasicLAF UI's look for. This causes problems for custom Basic-based UI's such as RTextAreaUI. This method attempts to detect if Nimbus has been installed, and if so, sets proper values for some editor properties.
      Parameters:
      editor - The text area.
    • create

      public View create(Element elem)
      Creates the view for an element. Returns a WrappedPlainView or PlainView.
      Specified by:
      create in interface ViewFactory
      Overrides:
      create in class BasicTextAreaUI
      Parameters:
      elem - The element.
      Returns:
      The view.
    • createCaret

      protected Caret createCaret()
      Returns the default caret for an RTextArea. This caret is capable of displaying itself differently for insert/overwrite modes.
      Overrides:
      createCaret in class BasicTextUI
      Returns:
      The caret.
    • createHighlighter

      protected Highlighter createHighlighter()
      Overrides:
      createHighlighter in class BasicTextUI
    • createKeymap

      protected Keymap createKeymap()
      Creates the keymap for this text area. This takes the super class's keymap, but sets the default keystroke to be RTextAreaEditorKit's DefaultKeyTypedAction. This must be done to override the default keymap's default key-typed action.
      Overrides:
      createKeymap in class BasicTextUI
      Returns:
      The keymap.
    • createRTextAreaActionMap

      protected ActionMap createRTextAreaActionMap()
      Creates a default action map. This action map contains actions for all basic text area work - cut, copy, paste, select, caret motion, etc.

      This isn't named createActionMap() because there is a package-private member by that name in BasicTextAreaUI, and some compilers will give warnings that we are not overriding that method since it is package-private.

      Returns:
      The action map.
    • getActionMapName

      protected String getActionMapName()
      Returns the name to use to cache/fetch the shared action map. This should be overridden by subclasses if the subclass has its own custom editor kit to install, so its actions get picked up.
      Returns:
      The name of the cached action map.
    • getEditorKit

      public EditorKit getEditorKit(JTextComponent tc)
      Fetches the EditorKit for the UI.
      Overrides:
      getEditorKit in class BasicTextUI
      Parameters:
      tc - the text component for which this UI is installed
      Returns:
      the editor capabilities
      See Also:
    • getRTextArea

      public RTextArea getRTextArea()
      Returns the text area for which we are the UI.
      Returns:
      The text area.
    • getRTextAreaActionMap

      private ActionMap getRTextAreaActionMap()
      Returns an action map to use by a text area.

      This method is not named getActionMap() because there is a package-private method in BasicTextAreaUI with that name. Thus, creating a new method with that name causes certain compilers to issue warnings that you are not actually overriding the original method (since it is package-private).

      Returns:
      The action map.
      See Also:
    • getRTextAreaInputMap

      protected InputMap getRTextAreaInputMap()
      Get the InputMap to use for the UI.

      This method is not named getInputMap() because there is a package-private method in BasicTextAreaUI with that name. Thus, creating a new method with that name causes certain compilers to issue warnings that you are not actually overriding the original method (since it is package-private).

    • getVisibleEditorRect

      protected Rectangle getVisibleEditorRect()
      Gets the allocation to give the root View. Due to an unfortunate set of historical events this method is inappropriately named. The Rectangle returned has nothing to do with visibility. The component must have a non-zero positive size for this translation to be computed.
      Overrides:
      getVisibleEditorRect in class BasicTextUI
      Returns:
      the bounding box for the root view
    • installDefaults

      protected void installDefaults()
      Overrides:
      installDefaults in class BasicTextAreaUI
    • installKeyboardActions

      protected void installKeyboardActions()
      Overrides:
      installKeyboardActions in class BasicTextUI
    • installUI

      public void installUI(JComponent c)
      Installs this UI to the given text component.
      Overrides:
      installUI in class BasicTextUI
    • paintBackground

      protected void paintBackground(Graphics g)
      Overrides:
      paintBackground in class BasicTextUI
    • paintCurrentLineHighlight

      protected void paintCurrentLineHighlight(Graphics g, Rectangle visibleRect)
      Paints the highlighted current line, if it is enabled.
      Parameters:
      g - The graphics context with which to paint.
      visibleRect - The visible rectangle of the text area.
    • paintEditorAugmentations

      protected void paintEditorAugmentations(Graphics g)
      Paints editor augmentations added by RTextArea: highlighted lines, current line highlight, and margin line.
      Parameters:
      g - The graphics context with which to paint.
    • paintLineHighlights

      protected void paintLineHighlights(Graphics g)
      Paints any line highlights.
      Parameters:
      g - The graphics context.
    • paintMarginLine

      protected void paintMarginLine(Graphics g, Rectangle visibleRect)
      Draws the "margin line" if enabled.
      Parameters:
      g - The graphics context to paint with.
      visibleRect - The visible rectangle of this text area.
    • paintSafely

      protected void paintSafely(Graphics g)
      Overrides:
      paintSafely in class BasicTextUI
    • yForLine

      public int yForLine(int line) throws BadLocationException
      Returns the y-coordinate of the specified line.

      The default implementation is equivalent to:

       int startOffs = textArea.getLineStartOffset(line);
       return yForLineContaining(startOffs);
       
      Subclasses that can calculate this value more quickly than traditional BasicTextUI.modelToView(JTextComponent, int) calls should override this method to do so. This method may be used when the entire bounding box isn't needed, to speed up rendering.
      Parameters:
      line - The line number.
      Returns:
      The y-coordinate of the top of the line, or -1 if this text area doesn't yet have a positive size or the line is hidden (i.e. from folding).
      Throws:
      BadLocationException - If line isn't a valid line number for this document.
    • yForLineContaining

      public int yForLineContaining(int offs) throws BadLocationException
      Returns the y-coordinate of the line containing an offset.

      The default implementation is equivalent to:

       int line = textArea.getLineOfOffset(offs);
       int startOffs = textArea.getLineStartOffset(line);
       return modelToView(startOffs).y;
       
      Subclasses that can calculate this value more quickly than traditional BasicTextUI.modelToView(JTextComponent, int) calls should override this method to do so. This method may be used when the entire bounding box isn't needed, to speed up rendering.
      Parameters:
      offs - The offset info the document.
      Returns:
      The y-coordinate of the top of the offset, or -1 if this text area doesn't yet have a positive size or the line is hidden (i.e. from folding).
      Throws:
      BadLocationException - If offs isn't a valid offset into the document.