Module java.desktop

Class GlyphView

java.lang.Object
javax.swing.text.View
javax.swing.text.GlyphView
All Implemented Interfaces:
Cloneable, SwingConstants, TabableView
Direct Known Subclasses:
LabelView

public class GlyphView extends View implements TabableView, Cloneable
A GlyphView is a styled chunk of text that represents a view mapped over an element in the text model. This view is generally responsible for displaying text glyphs using character level attributes in some way. An implementation of the GlyphPainter class is used to do the actual rendering and model/view translations. This separates rendering from layout and management of the association with the model.

The view supports breaking for the purpose of formatting. The fragments produced by breaking share the view that has primary responsibility for the element (i.e. they are nested classes and carry only a small amount of state of their own) so they can share its resources.

Since this view represents text that may have tabs embedded in it, it implements the TabableView interface. Tabs will only be expanded if this view is embedded in a container that does tab expansion. ParagraphView is an example of a container that does tab expansion.

Since:
1.3
  • Constructor Details

    • GlyphView

      public GlyphView(Element elem)
      Constructs a new view wrapped on an element.
      Parameters:
      elem - the element
  • Method Details

    • clone

      protected final Object clone()
      Creates a shallow copy. This is used by the createFragment and breakView methods.
      Overrides:
      clone in class Object
      Returns:
      the copy
      See Also:
      Cloneable
    • getGlyphPainter

      public GlyphView.GlyphPainter getGlyphPainter()
      Fetch the currently installed glyph painter. If a painter has not yet been installed, and a default was not yet needed, null is returned.
      Returns:
      the currently installed glyph painter
    • setGlyphPainter

      public void setGlyphPainter(GlyphView.GlyphPainter p)
      Sets the painter to use for rendering glyphs.
      Parameters:
      p - the painter to use for rendering glyphs
    • getText

      public Segment getText(int p0, int p1)
      Fetch a reference to the text that occupies the given range. This is normally used by the GlyphPainter to determine what characters it should render glyphs for.
      Parameters:
      p0 - the starting document offset >= 0
      p1 - the ending document offset >= p0
      Returns:
      the Segment containing the text
    • getBackground

      public Color getBackground()
      Fetch the background color to use to render the glyphs. If there is no background color, null should be returned. This is implemented to call StyledDocument.getBackground if the associated document is a styled document, otherwise it returns null.
      Returns:
      the background color to use to render the glyphs
    • getForeground

      public Color getForeground()
      Fetch the foreground color to use to render the glyphs. If there is no foreground color, null should be returned. This is implemented to call StyledDocument.getBackground if the associated document is a StyledDocument. If the associated document is not a StyledDocument, the associated components foreground color is used. If there is no associated component, null is returned.
      Returns:
      the foreground color to use to render the glyphs
    • getFont

      public Font getFont()
      Fetch the font that the glyphs should be based upon. This is implemented to call StyledDocument.getFont if the associated document is a StyledDocument. If the associated document is not a StyledDocument, the associated components font is used. If there is no associated component, null is returned.
      Returns:
      the font that the glyphs should be based upon
    • isUnderline

      public boolean isUnderline()
      Determine if the glyphs should be underlined. If true, an underline should be drawn through the baseline.
      Returns:
      if the glyphs should be underlined
    • isStrikeThrough

      public boolean isStrikeThrough()
      Determine if the glyphs should have a strikethrough line. If true, a line should be drawn through the center of the glyphs.
      Returns:
      if the glyphs should have a strikethrough line
    • isSubscript

      public boolean isSubscript()
      Determine if the glyphs should be rendered as superscript.
      Returns:
      if the glyphs should be rendered as superscript
    • isSuperscript

      public boolean isSuperscript()
      Determine if the glyphs should be rendered as subscript.
      Returns:
      if the glyphs should be rendered as subscript
    • getTabExpander

      public TabExpander getTabExpander()
      Fetch the TabExpander to use if tabs are present in this view.
      Returns:
      the TabExpander to use if tabs are present in this view
    • checkPainter

      protected void checkPainter()
      Check to see that a glyph painter exists. If a painter doesn't exist, a default glyph painter will be installed.
    • getTabbedSpan

      public float getTabbedSpan(float x, TabExpander e)
      Determines the desired span when using the given tab expansion implementation.
      Specified by:
      getTabbedSpan in interface TabableView
      Parameters:
      x - the position the view would be located at for the purpose of tab expansion >= 0.
      e - how to expand the tabs when encountered.
      Returns:
      the desired span >= 0
      See Also:
      TabableView.getTabbedSpan(float, javax.swing.text.TabExpander)
    • getPartialSpan

      public float getPartialSpan(int p0, int p1)
      Determines the span along the same axis as tab expansion for a portion of the view. This is intended for use by the TabExpander for cases where the tab expansion involves aligning the portion of text that doesn't have whitespace relative to the tab stop. There is therefore an assumption that the range given does not contain tabs.

      This method can be called while servicing the getTabbedSpan or getPreferredSize. It has to arrange for its own text buffer to make the measurements.

      Specified by:
      getPartialSpan in interface TabableView
      Parameters:
      p0 - the starting document offset >= 0
      p1 - the ending document offset >= p0
      Returns:
      the span >= 0
    • getStartOffset

      public int getStartOffset()
      Fetches the portion of the model that this view is responsible for.
      Overrides:
      getStartOffset in class View
      Returns:
      the starting offset into the model
      See Also:
      View.getStartOffset()
    • getEndOffset

      public int getEndOffset()
      Fetches the portion of the model that this view is responsible for.
      Overrides:
      getEndOffset in class View
      Returns:
      the ending offset into the model
      See Also:
      View.getEndOffset()
    • paint

      public void paint(Graphics g,