edu.umd.cs.jazz.component
Class ZLabel

java.lang.Object
  |
  +--edu.umd.cs.jazz.ZSceneGraphObject
        |
        +--edu.umd.cs.jazz.ZVisualComponent
              |
              +--edu.umd.cs.jazz.component.ZLabel

All Implemented Interfaces:

java.lang.Cloneable, java.io.Serializable, ZAppearance, ZPenColor, ZSerializable

public class ZLabel

extends ZVisualComponent

implements ZPenColor, java.io.Serializable

ZLabel creates a lightweight visual component to support a label containing one line of text. The label object is positioned so that its upper-left corner is at the origin, but this position can be altered with the setTranslate() methods.

Warning: Serialized and ZSerialized objects of this class will not be compatible with future Jazz releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Jazz. A future release of Jazz will provide support for long term persistence.

See Also:

Serialized Form

LOW_QUALITY_FONT_CONTEXT

protected static final java.awt.font.FontRenderContext LOW_QUALITY_FONT_CONTEXT

The low quality graphic2D render context: not antiAliased, and does not use FractionalMetrics.

HIGH_QUALITY_FONT_CONTEXT

protected static final java.awt.font.FontRenderContext HIGH_QUALITY_FONT_CONTEXT

The high quality graphic2D render context: AntiAliased, and uses FractionalMetrics.

DEFAULT_FONT_NAME

protected static final java.lang.String DEFAULT_FONT_NAME

Default font name of text.

See Also:

Constant Field Values

DEFAULT_FONT_STYLE

protected static final int DEFAULT_FONT_STYLE

Default font style for text.

See Also:

Constant Field Values

DEFAULT_FONT_SIZE

protected static final int DEFAULT_FONT_SIZE

Default font size for text.

See Also:

Constant Field Values

DEFAULT_FONT

protected static final java.awt.Font DEFAULT_FONT

Default font for text.

DEFAULT_PEN_COLOR

protected static final java.awt.Color DEFAULT_PEN_COLOR

Default color for text.

DEFAULT_BACKGROUND_COLOR

protected static final java.awt.Color DEFAULT_BACKGROUND_COLOR

Default background color for label.

DEFAULT_TEXT

protected static final java.lang.String DEFAULT_TEXT

Default text when new text area is created.

See Also:

Constant Field Values

penColor

protected java.awt.Color penColor

Current pen color.

backgroundColor

protected java.awt.Color backgroundColor

Background color for label.

font

protected java.awt.Font font

Current text font.

line

protected java.lang.String line

A label can hold one line of text.

boundsBug

protected boolean boundsBug

jdk version <= 1.2.1 has a bug: font.getStringBounds() gives the bounds of a space " " as zero.

translateX

protected double translateX

Translation offset X.

translateY

protected double translateY

Translation offset Y.

ZLabel

public ZLabel()

Default constructor for ZLabel.

ZLabel

public ZLabel(java.lang.String str)

ZLabel constructor with initial text.

ZLabel

public ZLabel(java.lang.String str,
              java.awt.Font font)

ZLabel constructor with initial text and font.

duplicateObject

protected java.lang.Object duplicateObject()

Returns a clone of this object.

Overrides:

duplicateObject in class ZVisualComponent

See Also:

ZSceneGraphObject.duplicateObject()

getPenColor

public java.awt.Color getPenColor()

Returns the current pen color.

Specified by:

getPenColor in interface ZPenColor

Returns:

the pen color, or null if none.

setPenColor

public void setPenColor(java.awt.Color color)

Sets the current pen color.

Specified by:

setPenColor in interface ZPenColor

Parameters:

color - the pen color, or null if none.

getBackgroundColor

public java.awt.Color getBackgroundColor()

Returns the current background color.

setBackgroundColor

public void setBackgroundColor(java.awt.Color color)

Sets the current background color.

getFont

public java.awt.Font getFont()

Returns the current font.

getText

public java.lang.String getText()

Return the text within this label component.

setFont

public void setFont(java.awt.Font aFont)

Sets the font for the text.

Warning: Java has a serious bug in that it does not support very small fonts. In particular, fonts that are less than about a pixel high just don't work. Since in Jazz, it is common to create objects of arbitrary sizes, and then scale them, an application can easily create a text object with a very small font by accident. The workaround for this bug is to create a larger font for the text object, and then scale the node down correspondingly.

setText

public void setText(java.lang.String str)

Sets the text of this visual component to str.

setTranslateX

public void setTranslateX(double x)

Set label translation offset X.

Parameters:

x - the X translation.

getTranslateX

public double getTranslateX()

Get the X offset translation.

Returns:

the X translation.

setTranslateY

public void setTranslateY(double y)

Set label translation offset Y.

Parameters:

y - the Y translation.

getTranslateY

public double getTranslateY()

Get the Y offset translation.

Returns:

the Y translation.

setTranslation

public void setTranslation(double x,
                           double y)

Set the label translation offset to the specified position.

Parameters:

x - the X-coord of translation

y - the Y-coord of translation

setTranslation

public void setTranslation(java.awt.geom.Point2D p)

Set the label translation offset to point p.

Parameters:

p - The translation offset.

getTranslation

public java.awt.geom.Point2D getTranslation()

Get the text translation offset.

Returns:

The translation offset.

render

public void render(ZRenderContext renderContext)

Renders the label object

The transform, clip, and composite will be set appropriately when this object is rendered. It is up to this object to restore the transform, clip, and composite of the Graphics2D if this node changes any of them. However, the color, font, and stroke are unspecified by Jazz. This object should set those things if they are used, but they do not need to be restored.

Overrides:

render in class ZVisualComponent

Parameters:

renderContext - The graphics context to use for rendering.

See Also:

ZVisualComponent.paint(Graphics2D)

computeBounds

protected void computeBounds()

Notifies this object that it has changed and that it should update its notion of its bounding box.

Overrides:

computeBounds in class ZSceneGraphObject

setState

public void setState(java.lang.String fieldType,
                     java.lang.String fieldName,
                     java.lang.Object fieldValue)

Set some state of this object as it gets read back in. After the object is created with its default no-arg constructor, this method will be called on the object once for each bit of state that was written out through calls to ZObjectOutputStream.writeState() within the writeObject method.

Specified by:

setState in interface ZSerializable

Overrides:

setState in class ZVisualComponent

Parameters:

fieldType - The fully qualified type of the field

fieldName - The name of the field

fieldValue - The value of the field

writeObject

public void writeObject(ZObjectOutputStream out)
                 throws java.io.IOException

Write out all of this object's state.

Specified by:

writeObject in interface ZSerializable

Overrides:

writeObject in class ZVisualComponent

Parameters:

out - The stream that this object writes into

java.io.IOException