// File   : gui-appearance/font/fontdemo/FontDemo.java
// Purpose: Demo of how to work with fonts.  This class is primarily 
//          user interface.  The accomanying FontPanel class does the drawing.
// Author : Fred Swartz - 28 Sep 2006 - Placed in public domain.

package fontdemo;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Font;
import java.awt.GraphicsEnvironment;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Vector;
import javax.swing.BoxLayout;
import javax.swing.ButtonGroup;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JSlider;
import javax.swing.border.EmptyBorder;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

/////////////////////////////////////////////////////////////////////// FontDemo
class FontDemo extends JFrame {
    //=================================================================== fields
    private FontPanel  _displayArea;// Where the sample text is displayed.
    
    //... The following controls are instance variables because they are
    //    referenced at "runtime" in the listeners.  Alternate solutions:
    //    * Declare them as *final* local variables.
    //    * Obtain them from the Event object passed to the listeners, which
    //      is a good solution when a listener is shared (but not here).
    private JSlider    _sizeSlider; // Sets the font size.
    private JComboBox  _fontCombo;  // For selecting one of the installed fonts.
    private JCheckBox  _antialiasedCB; // To draw with antiliasing on/off.
    
    //================================================================ constants
    private static final int    INITIAL_SIZE  = 18;
    private static final int    INITIAL_STYLE = Font.PLAIN;
    private static final String INITIAL_STYLENAME = "Font.PLAIN";
    private static final String INITIAL_FONTNAME  = "Monospaced";
    
    //============================================================== constructor
    public FontDemo() {
        //... Create a FontPanel to display the fonts.
        _displayArea = new FontPanel(INITIAL_FONTNAME, INITIAL_STYLE, 
                INITIAL_SIZE, false);
        
        //... Get all font families
        String[] fontNames = GraphicsEnvironment
                .getLocalGraphicsEnvironment()
                .getAvailableFontFamilyNames();
        
        //... Make vector of all fonts that can display basic chars.
        //    Vector (not newer ArrayList) is used by JComboBox.
        Vector<String> visFonts = new Vector<String>(fontNames.length);
        for (String fontName : fontNames) {
            Font f = new Font(fontName, Font.PLAIN, 12);
            if (f.canDisplay('a')) {
                //... Display only fonts that have the alphabetic characters.
                visFonts.add(fontName);
            } else {
                //    On my machine there are almost 20 fonts (eg, Wingdings)
                //    that don't display text.
                //System.out.println("No alphabetics in " + fontName);
            }
        }
        
        _fontCombo = new JComboBox(visFonts);         // JComboBox of fonts
        _fontCombo.setSelectedItem(INITIAL_FONTNAME); // Select initial font
        _fontCombo.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                _displayArea.setFontName((String)_fontCombo.getSelectedItem());
            }
        });
        
        //... Style: Create radio buttons for the 4 style options.
        JRadioButton stylePlainRB  = new JRadioButton("Font.PLAIN", true);
        JRadioButton styleItalicRB = new JRadioButton("Font.ITALIC", false);
        JRadioButton styleBoldRB   = new JRadioButton("Font.BOLD", false);
        JRadioButton styleItalicBoldRB = new JRadioButton("Font.ITALIC+Font.BOLD"
                , false);
        
        //... Add the buttons to a button group
        ButtonGroup styleGroup = new ButtonGroup();
        styleGroup.add(stylePlainRB);
        styleGroup.add(styleItalicRB);
        styleGroup.add(styleBoldRB);
        styleGroup.add(styleItalicBoldRB);
        
        //... Add listeners.
        stylePlainRB.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                _displayArea.setFontStyle(Font.PLAIN);
            }
        });
        styleItalicRB.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                _displayArea.setFontStyle(Font.ITALIC);
            }
        });
        styleBoldRB.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                _displayArea.setFontStyle(Font.BOLD);
            }
        });
        styleItalicBoldRB.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                _displayArea.setFontStyle(Font.ITALIC + Font.BOLD);
            }
        });
        
        //... Antialiasing checkbox
        _antialiasedCB = new JCheckBox("Antialiased");
        _antialiasedCB.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                _displayArea.setAntialiasing(_antialiasedCB.isSelected());
            }
        });
        
        //... Create a slider for setting the size value
        _sizeSlider = new JSlider(JSlider.HORIZONTAL, 5, 60, INITIAL_SIZE);
        _sizeSlider.setMajorTickSpacing(10); // sets numbers for big tick marks
        _sizeSlider.setMinorTickSpacing(1);  // smaller tick marks
        _sizeSlider.setPaintTicks(true);     // display the ticks
        _sizeSlider.setPaintLabels(true);    // show the numbers
        _sizeSlider.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent e) {
                _displayArea.setFontSize(_sizeSlider.getValue());
            }
        });
        
        //... Controls arranged in BoxLayout.
        //    This is pretty ugly, but I didn't feel like struggling with
        //    GridBagLayout, and didn't want to use any of the superior
        //    external layout managers in this program.
        JPanel controls = new JPanel();
        controls.setLayout(new BoxLayout(controls, BoxLayout.Y_AXIS));
        
        //... Add components to controls panel.
        addToBox(controls, Component.LEFT_ALIGNMENT
                , new JLabel("Font:"), _fontCombo
                , new JLabel("Size:"), _sizeSlider
                , new JLabel("Style:"), stylePlainRB, styleItalicRB
                , styleBoldRB, styleItalicBoldRB
                , _antialiasedCB
                );
        
        //... Put display+controls in the content pane.
        JPanel content = new JPanel();
        content.setLayout(new BorderLayout(5, 5));
        content.add(_displayArea, BorderLayout.CENTER);
        content.add(controls, BorderLayout.WEST);
        content.setBorder(new EmptyBorder(12, 12, 12, 12));
        
        //... Set window characteristics
        setContentPane(content);
        setTitle("Font Demo");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
    }
    
    //================================================================= addToBox
    // Utility method to add elements to a BoxLayout container.
    private void addToBox(Container cont, float align, JComponent... comps ) {
        for (JComponent comp : comps) {
            comp.setAlignmentX(align);
            cont.add(comp);
        }
    }
    
    //===================================================================== main
    public static void main(String[] args) {
        JFrame myWindow = new FontDemo();
        myWindow.setVisible(true);
    }
}

// File   : gui-appearance/font/fontdemo/FontPanel.java
// Purpose: A component to draw sample string with given font family, style,
//          size, and aliasing.
// Author : Fred Swartz - 28 Sep 2006 - Placed in public domain.

package fontdemo;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.Rectangle2D;
import javax.swing.JPanel;

//////////////////////////////////////////////////////////////// FontPanel class
class FontPanel extends JPanel {
    private String _fontName;
    private int    _fontStyle;
    private int    _fontSize;
    private boolean _antialiased;
    
    //============================================================== constructor
    public FontPanel(String font, int style, int size, boolean antialiased) {
        this.setPreferredSize(new Dimension(400, 100));
        this.setBackground(Color.white);
        this.setForeground(Color.black);
        _fontName  = font;
        _fontStyle = style;
        _fontSize  = size;
        _antialiased = antialiased;
    }
    
    //================================================= @Override paintComponent
    @Override public void paintComponent(Graphics g) {
        super.paintComponent(g);        // Paint background.
        
        Graphics2D g2 = (Graphics2D)g;  // Graphics2 for antialiasing.
        
        String text = "Font(\""
                + _fontName + "\", "
                + fontStyleCodeToFontStyleString(_fontStyle) + ", "
                + _fontSize + ");";
        Font f = new Font(_fontName, _fontStyle, _fontSize);
        g2.setFont(f);
        
        if (_antialiased) {
            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                    RenderingHints.VALUE_ANTIALIAS_ON);
        }
        
        //... Find the size of this text so we can center it.
        FontMetrics fm = g2.getFontMetrics(f);  // metrics for this object
        Rectangle2D rect = fm.getStringBounds(text, g2); // size of string
        int textHeight  = (int)(rect.getHeight());
        int textWidth   = (int)(rect.getWidth());
        
        //... Center text horizontally and vertically
        int x = (this.getWidth()  - textWidth)  / 2;
        int y = (this.getHeight() - textHeight) / 2  + fm.getAscent();
        
        g2.drawString(text, x, y);
    }
    
    //================================================================== SETTERS
    public void setFontName(String fn)  { _fontName = fn;    this.repaint();}
    public void setFontSize(int size)   { _fontSize = size;  this.repaint();}
    public void setFontStyle(int style) {_fontStyle = style; this.repaint();}
    public void setAntialiasing(boolean antialiased) {
        _antialiased = antialiased;
        this.repaint();
    }
    
    //=========================================== fontStyleCodeToFontStyleString
    // Utility method for converting font codes to name.
    public static String fontStyleCodeToFontStyleString(int styleCode) {
        String styleName;
        switch (styleCode) {
            case Font.PLAIN:            styleName = "Font.PLAIN";       break;
            case Font.ITALIC:           styleName = "Font.ITALIC";      break;
            case Font.BOLD:             styleName = "Font.BOLD";        break;
            case Font.ITALIC+Font.BOLD: styleName = "ITALIC+Font.BOLD"; break;
            default: throw new IllegalArgumentException(
                    "fontStyleCodeToFontStyleString: Unknown font code: " +
                    styleCode);
        };
        return styleName;
    }
}