Package org.jdesktop.swingx.painter

Class CompoundPainter<T>

  • All Implemented Interfaces:
    Painter<T>
    Direct Known Subclasses:
    AlphaPainter, URLPainter
    public class CompoundPainter<T>
extends AbstractPainter<T>

    A Painter implementation composed of an array of Painters. CompoundPainter provides a means for combining several individual Painters, or groups of them, into one logical unit. Each of the Painters are executed in order. BufferedImageOp filter effects can be applied to them together as a whole. The entire set of painting operations may be cached together.

    For example, if I want to create a CompoundPainter that started with a blue background, had pinstripes on it running at a 45 degree angle, and those pinstripes appeared to "fade in" from left to right, I would write the following: 

    
  Color blue = new Color(0x417DDD);
  Color translucent = new Color(blue.getRed(), blue.getGreen(), blue.getBlue(), 0);
  panel.setBackground(blue);
  panel.setForeground(Color.LIGHT_GRAY);
  GradientPaint blueToTranslucent = new GradientPaint(
    new Point2D.Double(.4, 0),
    blue,
    new Point2D.Double(1, 0),
    translucent);
  MattePainter veil = new MattePainter(blueToTranslucent);
  veil.setPaintStretched(true);
  Painter pinstripes = new PinstripePainter(45);
  Painter backgroundPainter = new RectanglePainter(this.getBackground(), null);
  Painter p = new CompoundPainter(backgroundPainter, pinstripes, veil);
  panel.setBackgroundPainter(p);

    Author:
    rbair

    • Constructor Detail

      • CompoundPainter

        public CompoundPainter()
        Creates a new instance of CompoundPainter

      • CompoundPainter

        public CompoundPainter​(Painter... painters)
        Convenience constructor for creating a CompoundPainter for an array of painters. A defensive copy of the given array is made, so that future modification to the array does not result in changes to the CompoundPainter.
        Parameters:
        painters - array of painters, which will be painted in order

    • Method Detail

      • setPainters

        public void setPainters​(Painter... painters)
        Sets the array of Painters to use. These painters will be executed in order. A null value will be treated as an empty array. To prevent unexpected behavior all values in provided array are copied to internally held array. Any changes to the original array will not be reflected.
        Parameters:
        painters - array of painters, which will be painted in order

      • getPainters

        public final Painter[] getPainters()
        Gets the array of painters used by this CompoundPainter
        Returns:
        a defensive copy of the painters used by this CompoundPainter. This will never be null.

      • isClipPreserved

        public boolean isClipPreserved()
        Indicates if the clip produced by any painter is left set once it finishes painting. Normally the clip will be reset between each painter. Setting clipPreserved to true can be used to let one painter mask other painters that come after it.
        Returns:
        if the clip should be preserved
        See Also:
        setClipPreserved(boolean)

      • setClipPreserved

        public void setClipPreserved​(boolean shouldRestoreState)
        Sets if the clip should be preserved. Normally the clip will be reset between each painter. Setting clipPreserved to true can be used to let one painter mask other painters that come after it.
        Parameters:
        shouldRestoreState - new value of the clipPreserved property
        See Also:
        isClipPreserved()

      • getTransform

        public java.awt.geom.AffineTransform getTransform()
        Gets the current transform applied to all painters in this CompoundPainter. May be null.
        Returns:
        the current AffineTransform

      • setTransform

        public void setTransform​(java.awt.geom.AffineTransform transform)
        Set a transform to be applied to all painters contained in this CompoundPainter
        Parameters:
        transform - a new AffineTransform

      • validate

        protected void validate​(T object)

        Iterates over all child Painters and gives them a chance to validate themselves. If any of the child painters are dirty, then this CompoundPainter marks itself as dirty.

        Called to allow Painter subclasses a chance to see if any state in the given object has changed from the last paint operation. If it has, then the Painter has a chance to mark itself as dirty, thus causing a repaint, even if cached.

        Overrides:
        validate in class AbstractPainter<T>

      • isCheckingDirtyChildPainters

        public boolean isCheckingDirtyChildPainters()
        Used by isDirty() to check if the child Painters should be checked for their dirty flag as part of processing.
        Default value is: true
        This should be set to false if the cacheable state of the child Painters are different from each other. This will allow the cacheable == true Painters to keep their cached image during regular repaints. In this case, client code should call clearCache() manually when the cacheable Painters should be updated.
        See Also:
        isDirty()

      • setCheckingDirtyChildPainters

        public void setCheckingDirtyChildPainters​(boolean b)
        Set the flag used by isDirty() to check if the child Painters should be checked for their dirty flag as part of processing.
        See Also:
        isCheckingDirtyChildPainters(), isDirty()

      • isDirty

        protected boolean isDirty()

        This CompoundPainter is dirty if it, or (optionally) any of its children, are dirty. If the super implementation returns true, we return true. Otherwise, if isCheckingDirtyChildPainters() is true, we iterate over all child Painters and query them to see if they are dirty. If so, then true is returned. Otherwise, we return false.

        Ye olde dirty bit. If true, then the painter is considered dirty and in need of being repainted. This is a bound property. {@see #isCheckingDirtyChildPainters()}
        Overrides:
        isDirty in class AbstractPainter<T>
        Returns:
        true if the painter state has changed and the painter needs to be repainted.

      • setDirty

        protected void setDirty​(boolean d)
        Sets the dirty bit. If true, then the painter is considered dirty, and the cache will be cleared. This property is bound.
        Overrides:
        setDirty in class AbstractPainter<T>
        Parameters:
        d - whether this Painter is dirty.

      • clearCache

        public void clearCache()

        Clears the cache of this Painter, and all child Painters. This is done to ensure that resources are collected, even if clearCache is called by some framework or other code that doesn't realize this is a CompoundPainter.

        Call #clearLocalCache if you only want to clear the cache of this CompoundPainter

        Call this method to clear the cacheable. This may be called whether there is a cacheable being used or not. If cleared, on the next call to paint, the painting routines will be called.

        SubclassesIf overridden in subclasses, you must call super.clearCache, or physical resources (such as an Image) may leak.

        Overrides:
        clearCache in class AbstractPainter<T>

      • clearLocalCache

        public void clearLocalCache()

        Clears the cache of this painter only, and not of any of the children.

      • doPaint

        protected void doPaint​(java.awt.Graphics2D g,
                       T component,
                       int width,
                       int height)
        Subclasses must implement this method and perform custom painting operations here.
        Specified by:
        doPaint in class AbstractPainter<T>
        Parameters:
        g - The Graphics2D object in which to paint

      • configureGraphics

        protected void configureGraphics​(java.awt.Graphics2D g)

        This method is called by the paint method prior to any drawing operations to configure the drawing surface. The default implementation sets the rendering hints that have been specified for this AbstractPainter.

        This method can be overridden by subclasses to modify the drawing surface before any painting happens.

        Overrides:
        configureGraphics in class AbstractPainter<T>
        Parameters:
        g - the graphics surface to configure. This will never be null.
        See Also:
        AbstractPainter.paint(Graphics2D, Object, int, int)

      • shouldUseCache

        protected boolean shouldUseCache()

        Returns true if the painter should use caching. This method allows subclasses to specify the heuristics regarding whether to cache or not. If a Painter has intelligent rules regarding painting times, and can more accurately indicate whether it should be cached, it could implement that logic in this method.

        Overrides:
        shouldUseCache in class AbstractPainter<T>
        Returns:
        whether or not a cache should be used