theme.java

关于J4ME J2ME实例

package org.j4me.ui;

import javax.microedition.lcdui.*;
import org.j4me.util.*;

/**
 * Derive this class to set the application's theme.  A theme controls
 * the color scheme and background graphics used to skin the application.
 * <p>
 * Themes do not alter the shapes or functionality of components.  To
 * change the behavior of appearance of any component it is up to you to
 * derive a new component type and implement the changes. 
 */
public class Theme
{
	// Colors.
	//  There are many online lists of colors.  One is available at
	//  http://www.december.com/html/spec/colordec.html
	/** Black */		public static final int BLACK = 0x00000000;
	/** Brown */		public static final int BROWN = 0x00804000;
	/** Blue */			public static final int BLUE = 0x000000FF;
	/** Navy blue */	public static final int NAVY = 0x00000080;
	/** Neon blue */	public static final int NEON_BLUE = 0x004DFFFF;
	/** Light blue */	public static final int LIGHT_BLUE = 0x000080FF;
	/** Red */			public static final int RED = 0x00FF0000;
	/** Maroon */		public static final int MAROON = 0x00802020;
	/** Light red */	public static final int LIGHT_RED = 0x00FF5050;
	/** Magenta */		public static final int MAGENTA = 0x00FF28FF;
	/** Orange */		public static final int ORANGE = 0x00FF8000;
	/** Burnt orange */	public static final int BURNT_ORANGE = 0x00D07000;
	/** Yellow */		public static final int YELLOW = 0x00FFFF00;
	/** Green */		public static final int GREEN = 0x0066FF33;
	/** Medium green */	public static final int MEDIUM_GREEN = 0x0000A700;
	/** Light green */	public static final int LIGHT_GREEN = 0x0030C020;
	/** Dark green */	public static final int DARK_GREEN = 0x001F432D;
	/** Forest green*/	public static final int FOREST_GREEN = 0x0033773A;
	/** Blue-green */	public static final int BLUE_GREEN = 0x00008080;
	/** Cyan */			public static final int CYAN = 0x0033FFFF;
	/** Silver */		public static final int SILVER = 0x00C0C0C0;
	/** Gray */			public static final int GRAY = 0x00808080;
	/** Light gray */	public static final int LIGHT_GRAY = 0x00C0C0C0;
	/** Lavendar */		public static final int LAVENDAR = 0x00E6E6FA;
	/** White */		public static final int WHITE = 0x00FFFFFF;
	
	/**
	 * The percentage of the way down the title bar that the secondary color
	 * used in the gradient fill is at its max.
	 */
	private static final double TITLE_BAR_SECONDARY_COLOR_MAX = 0.60;  // 60%
	
	/**
	 * The percentage of the way down the menu bar that the secondary color
	 * used in the gradient fill is at its max.
	 */
	private static final double MENU_BAR_SECONDARY_COLOR_MAX = 0.10;  // 10%
	
	/**
	 * The percentage of the way across the scrollbar that the secondary color
	 * used in the gradient fill is at its max.
	 */
	private static final double SCROLLBAR_SECONDARY_COLOR_MAX = 0.80;  // 80%
	
	/**
	 * The width of the scrollbar in pixels.
	 */
	private static final int SCROLLBAR_WIDTH = 6;
	
	/**
	 * The font used for writing text in the normal canvas area.  It
	 * is the default font used by components.
	 */
	private final Font defaultFont;
	
	/**
	 * The font used to write menu bar options.
	 */
	private final Font menuFont;
	
	/**
	 * The font used in the title area.
	 */
	private final Font titleFont;
	
	/**
	 * Creates a <code>Theme</code> object.  After creating the theme it must
	 * be attached to the UI manager to use it through the <code>setTheme</code>
	 * method.
	 */
	public Theme ()
	{
		// Get the application's fonts.
		Font base = Font.getDefaultFont();
		int face = base.getFace();
		int size = base.getSize();
		
		defaultFont = Font.getFont( face, Font.STYLE_PLAIN, size );
		menuFont = Font.getFont( face, Font.STYLE_PLAIN, size );
		titleFont = Font.getFont( face, Font.STYLE_BOLD, size );
	}
	
	/**
	 * Gets the basic default font.  This font is used for writing menu
	 * options, labels, and regular text throughout the UI.
	 * 
	 * @return The font used for normal text within the UI.
	 * @see #getFontColor()
	 */
	public Font getFont ()
	{
		return defaultFont;
	}

	/**
	 * Returns the font used in the menu bar at the bottom of the canvas.
	 * <p>
	 * By default this font is the system font.
	 * Override this font to change the style of the title text.
	 * 
	 * @return The font used for writing menu text.
	 * 
	 * @see #getMenuFontColor()
	 * @see #paintMenuBar(Graphics, String, boolean, String, boolean, int, int)
	 */
	public Font getMenuFont ()
	{
		return menuFont;
	}
	
	/**
	 * Returns the font used for writing the title in the screen's title
	 * area.
	 * <p>
	 * By default this font is the system font in bold.
	 * Override this font to change the style of the title text.
	 * 
	 * @return The font used for writing the title in the title area at
	 *  the top of the screen.
	 * @see #getTitleFontColor()
	 * @see #paintTrackbar(Graphics, int, int, int, int)
	 */
	public Font getTitleFont ()
	{
		return titleFont;
	}
	
	/**
	 * The color of the text written with the font returned by <code>getFont</code>.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change the text color.
	 *  
	 * @return The color of text written with the font from <code>getFont</code>.
	 * @see #getFontColor()
	 */
	public int getFontColor ()
	{
		return NAVY;
	}
	
	/**
	 * The color of the text written with the font returned by <code>getMenuFont</code>.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change the text color.
	 *  
	 * @return The color of text written with the font from <code>getMenuFont</code>.
	 * @see #getMenuFont()
	 * @see #paintMenuBar(Graphics, String, boolean, String, boolean, int, int)
	 */
	public int getMenuFontColor ()
	{
		return WHITE;
	}
	
	/**
	 * The color of the menu text when the menu button is pressed.  Normally it
	 * will be the color returned by <code>getMenuFontColor</code>.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change the text color.
	 *  
	 * @return The color of the menu text when its menu button is pressed.
	 * @see #getMenuFont()
	 * @see #getMenuFontColor()
	 * @see #paintMenuBar(Graphics, String, boolean, String, boolean, int, int)
	 */
	public int getMenuFontHighlightColor ()
	{
		return SILVER;
	}
	
	/**
	 * The color of the text written with the font returned by <code>getTitleFont</code>.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change the text color.
	 *  
	 * @return The color of text written with the font from <code>getTitleFont</code>.
	 * @see #getTitleFont()
	 * @see #paintTrackbar(Graphics, int, int, int, int)
	 */
	public int getTitleFontColor ()
	{
		return getMenuFontColor();
	}

	/**
	 * Returns the color used for borders in the canvas section of the
	 * UI.  An example of a border is the outline around a text box.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel
	 * is ignored.
	 * <p>
	 * Override this method to change it. 
	 * 
	 * @return The color of the borders in the UI.
	 */
	public int getBorderColor ()
	{
		return NAVY;
	}
	
	/**
	 * Returns the color used as the background for the canvas section
	 * of the screen.  This is the area that is not the title bar
	 * at the top or menu bar at the bottom.  Colors are defined as
	 * 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change it.
	 * 
	 * @return The color of the title border.
	 */
	public int getBackgroundColor ()
	{
		return WHITE;
	}
	
	/**
	 * Returns the main color used in painting components.  For example
	 * a progress bar will use this color to show the completed progress.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel
	 * is ignored.
	 * <p>
	 * Override this method to change it. 
	 * 
	 * @return The primary color used to paint components.
	 */
	public int getHighlightColor ()
	{
		return LIGHT_BLUE;
	}
	
	/**
	 * Returns the color of the border around the title bar.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * By default this is the same color as the menu border.  Override
	 * this method to change it.
	 * 
	 * @return The color of the title border.
	 * @see #paintTrackbar(Graphics, int, int, int, int)
	 */
	public int getTitleBarBorderColor ()
	{
		return getMenuBarBorderColor();
	}
	
	/**
	 * Returns the primary color of the background of the title bar.  A second
	 * color defined by <code>getTitleBarHighlightColor</code> is overlaid with
	 * a vertical gradient.
	 * <p>
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * By default this is the same color as the menu bar background.  Override
	 * this method to change it.
	 * 
	 * @return The primary color of the title bar background.
	 * 
	 * @see #getTitleBarHighlightColor()
	 */
	public int getTitleBarBackgroundColor ()
	{
		return getMenuBarBackgroundColor();
	}

	/**
	 * Returns the highlight color applied as a vertical gradient to the title
	 * bar.
	 * <p>
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * By default this is the same color as the menu bar highlight.  Override
	 * this method to change it.
	 * 
	 * @return The highlight color of the title bar background.
	 * 
	 * @see #getTitleBarBackgroundColor()
	 */
	public int getTitleBarHighlightColor ()
	{
		return getMenuBarHighlightColor();
	}
	
	/**
	 * Returns the color of the border around the menu bar.
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change it.
	 * 
	 * @return The color of the border around the menu bar.
	 * @see #paintMenuBar(Graphics, String, boolean, String, boolean, int, int)
	 */
	public int getMenuBarBorderColor ()
	{
		return getFontColor();
	}
	
	/**
	 * Returns the primary color of the background of the menu  bar.  A second
	 * color defined by <code>getMenuBarHighlightColor</code> is overlaid with
	 * a vertical gradient.
	 * <p>
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change it.
	 * 
	 * @return The color of the border around the menu bar.
	 * 
	 * @see #getMenuBarHighlightColor()
	 */
	public int getMenuBarBackgroundColor ()
	{
		return NAVY;
	}
	
	/**
	 * Returns the highlight color applied as a vertical gradient to the menu
	 * bar.
	 * <p>
	 * Colors are defined as 0xAARRGGBB; the first-byte alpha-channel is ignored.
	 * <p>
	 * Override this method to change it.
	 * 
	 * @return The highlight color of the menu bar background.
	 * 
	 * @see #getMenuBarBackgroundColor()
	 */
	public int getMenuBarHighlightColor ()
	{
		return LIGHT_BLUE;
	}
	
	/**
	 * Gets the height of the title bar in pixels.  This method is called
	 * whenever the title is set and the title bar is going to be painted.
	 * 
	 * @return The height of the title bar in pixels.
	 * @see #paintTrackbar(Graphics, int, int, int, int)
	 */
	public int getTitleHeight ()
	{
		return getTitleFont().getHeight() + 2;
	}
	
	/**
	 * Paints the title bar of the canvas.  This method is called only
	 * when the title has been set through <code>setTitle</code> and the canvas
	 * is not in full screen mode.
	 * <p>
	 * The supplied <code>Graphics</code> will be set with an appropriate clip
	 * and translated such that (0,0) is the top-left corner of the title
	 * bar.
	 * <p>
	 * Override this method to change the appearance of the title bar.
	 * For example background or logo images can be placed throughout the
	 * application by painting them here.
	 * 
	 * @param g is the <code>Graphics</code> object to paint with.
	 * @param title is the text for the title bar as defined by the
	 *  canvas class.
	 * @param width is the width of the title bar in pixels.
	 * @param height is the height of the title bar in pixels.
	 */
	public void paintTitleBar (Graphics g, String title, int width, int height)
	{
		// Fill the background of the title bar.
		paintTitleBarBackground( g, 0, 0, width, height );
		
		// Draw a line below the title bar to separate it from the canvas.
		g.setColor( getTitleBarBorderColor() );
		g.drawLine( 0, height - 1, width, height - 1 );

		// Write the title text.
		g.setFont( getTitleFont() );
		g.setColor( getTitleFontColor() );
		g.drawString( title, width / 2, 1, Graphics.HCENTER | Graphics.TOP );
	}
	
	/**
	 * Paints the background area of the title bar.  The text will be
	 * added later by the calling <code>paintTitleBar</code> method.
	 *
	 * @param g is the <code>Graphics</code> object to paint with.
	 * @param x is the top-left X-coordinate pixel of the title bar.
	 * @param y is the top-left Y-coordinate pixel of the title bar.
	 * @param width is the width of the title bar in pixels.