Font | Tech Tips & Tricks

Set Font In JEditorPane Or JTextPane

August 11, 2010 by blogmeister·0 Comments

Setting the font of either a JEditorPane or JTextPane is not possible by doing it directly. However, you can do that by setting it in the EditorKit class. This post uses the RTFEditorKit class as an example of the editor kit used by a JEditorPane.

I created a custom class that inherits the RTFEditorKit to make things simpler. Just call initializeDefaultFont() to set the font to the JEditorPane. However, a very important thing to note is that this method should only be called after the RTFEditorKit object is set to the JEditorPane.setEditorKit() method. If the initializeDefaultFont() is called before that, the font will not be set.

To use the class. Check the sample code below.

JEditorPane ep = new JEditorPane();
MyRTFEditorKit rtfkit = new MyRTFEditorKit();
ep.setEditorKit(rtfkit);
rtfkit.initializeDefaultFont();

JEditorPane ep = new JEditorPane();

MyRTFEditorKit rtfkit = new MyRTFEditorKit();

ep.setEditorKit(rtfkit);

rtfkit.initializeDefaultFont();

And the MyRTFEditor.java class is below.

public class MyRTFEditorKit extends RTFEditorKit {
    private MutableAttributeSet attr = null;
    private Font font = new Font("Arial", Font.PLAIN, 12);
    public void initializeDefaultFont() {
        if (attr == null)
            attr = new SimpleAttributeSet();
        StyleConstants.setFontFamily(attr, font.getFontName());
        StyleConstants.setFontSize(attr, font.getSize());
        StyleConstants.setForeground(attr, Color.black);
        if (Default.RTF_FONT.isBold())
            StyleConstants.setBold(attr, true);
        else
            StyleConstants.setBold(attr, false);
        if (Default.RTF_FONT.isItalic())
            StyleConstants.setItalic(attr, true);
        else
            StyleConstants.setItalic(attr, false);
        // set default font in rtf editor kit
        MutableAttributeSet iattr = getInputAttributes();
        iattr.removeAttribute(attr);
        iattr.addAttributes(attr);
    }
}

public class MyRTFEditorKit extends RTFEditorKit {

private MutableAttributeSet attr = null;

private Font font = new Font("Arial", Font.PLAIN, 12);

public void initializeDefaultFont() {

if (attr == null)

attr = new SimpleAttributeSet();

StyleConstants.setFontFamily(attr, font.getFontName());

StyleConstants.setFontSize(attr, font.getSize());

StyleConstants.setForeground(attr, Color.black);

if (Default.RTF_FONT.isBold())

StyleConstants.setBold(attr, true);

else

StyleConstants.setBold(attr, false);

if (Default.RTF_FONT.isItalic())

StyleConstants.setItalic(attr, true);

else

StyleConstants.setItalic(attr, false);

// set default font in rtf editor kit

MutableAttributeSet iattr = getInputAttributes();

iattr.removeAttribute(attr);

iattr.addAttributes(attr);

}

Change Tree Node’s Font Attributes In Java

October 18, 2009 by blogmeister·0 Comments

You can easily change the font attributes like bold and italic of a JTree‘s tree node (parent or leaf node) by overriding the DefaultTreeCellRenderer class getTreeCellRendererComponent() method. Then you can set the JTree’s setRenderer() method to this renderer object.

public class MyTreeCellRenderer extends DefaultTreeCellRenderer {
    @Override
    public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected, boolean expanded, boolean leaf, int row, boolean hasFocus) {
        super.getTreeCellRendererComponent(tree, value, selected, expanded, leaf, row, hasFocus);
        if (selected) {
            setFont(getFont().deriveFont(Font.BOLD + Font.ITALIC));
        } else setFont(getFont().deriveFont(Font.PLAIN));
       return this;
    }
}

public class MyTreeCellRenderer extends DefaultTreeCellRenderer {

@Override

public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected, boolean expanded, boolean leaf, int row, boolean hasFocus) {

super.getTreeCellRendererComponent(tree, value, selected, expanded, leaf, row, hasFocus);

if (selected) {

setFont(getFont().deriveFont(Font.BOLD + Font.ITALIC));

} else setFont(getFont().deriveFont(Font.PLAIN));

return this;

}

The code above sets the tree node’s font attributes (in this case bold and italic) if it is selected. If you want all tree nodes to have these same font attributes, you can remove the if condition statement.

Resize Width Of JTree Selected Node On Font Change

September 25, 2009 by blogmeister·1 Comment

Say you want your selected JTree node to have its text in bold and italicized, once you click on the node, the text (if long) more or less gets truncated with … and you do not want to see that in your JTree right? What you need to do is override the getPreferredSize() method of the DefaultTreeCellRenderer. mimiman_ from the Sun forum gave this piece of code.

It worked wonders!

public class MyTreeCellRenderer extends DefaultTreeCellRenderer {
	public Component getTreeCellRendererComponent(JTree tr, Object value, boolean sel, boolean expanded, boolean leaf, int row, boolean focus) {
		if (sel) this.setFont(getFont().deriveFont(Font.BOLD + Font.ITALIC));
		else this.setFont(getFont().deriveFont(Font.PLAIN));
		return this;
	}
         /**
          Add this override to recalculate the width of this JLabel.
           The super class default behaviour miscalculates the width, and so the 
           '...'  can appear. Instead, we 'simulate' the FontMetrics'                   
           stringWidth() method, by using charWidth(), plus some initialization 
           and padding
         */
    	public Dimension getPreferredSize() {
    		Dimension dim = super.getPreferredSize();
   		FontMetrics fm = getFontMetrics(getFont());
   		char[] chars = getText().toCharArray();
   		int w = getIconTextGap() + 16;
   		for (char ch : chars)  {
   			w += fm.charWidth(ch);
   		}
   		w += getText().length();
   		dim.width = w;
		return dim;
	}
}

public class MyTreeCellRenderer extends DefaultTreeCellRenderer {

public Component getTreeCellRendererComponent(JTree tr, Object value, boolean sel, boolean expanded, boolean leaf, int row, boolean focus) {

if (sel) this.setFont(getFont().deriveFont(Font.BOLD + Font.ITALIC));

else this.setFont(getFont().deriveFont(Font.PLAIN));

return this;

}

/**

Add this override to recalculate the width of this JLabel.

The super class default behaviour miscalculates the width, and so the

'...' can appear. Instead, we 'simulate' the FontMetrics'

stringWidth() method, by using charWidth(), plus some initialization

and padding

public Dimension getPreferredSize() {

Dimension dim = super.getPreferredSize();

FontMetrics fm = getFontMetrics(getFont());

char[] chars = getText().toCharArray();

int w = getIconTextGap() + 16;

for (char ch : chars) {

w += fm.charWidth(ch);

}

w += getText().length();

dim.width = w;

return dim;

}

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Tag: font

Set Font In JEditorPane Or JTextPane

Change Tree Node’s Font Attributes In Java

Resize Width Of JTree Selected Node On Font Change