Hi everyone,

                    I am currently trying to use a JTextPane as a cell
renderers for a JTable but it does not seem to work although the program
compiles. I alsways get an error stating class cast exception saying that
i must cast the editor component to JTextField instead of a JTextPane
although i am using a JTextPane as a cell renderer.

                     This exeption gets thrown when i try to apply some
font to the selected text in the JTextPane.

                    Below is a small compilable that i have done which
compiles and throws the exception that i have mentioned about

Here is the compilable example

import java.awt.*;
import java.awt.image.*;
import java.io.*;
import java.text.*;
import java.awt.event.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;
import javax.swing.text.*;

public class TabTest implements ActionListener, ItemListener

{

	JFrame fr = new JFrame ("Frame");


	JButton Button1 = new JButton("Add Coloum");
	JButton Button2 = new JButton("Add Row");

	JComboBox ComboBox1;

	DefaultTableModel TableModel1 = new DefaultTableModel(0, 0);

	JTable Table1 = new JTable(TableModel1);

	JScrollPane ScrollPane1 = new JScrollPane(Table1,
ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS, 
	ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);  

	String FontFamily = "Arial";

	Dimension Size1 = new Dimension();

	//add
	//The below command line is the constructor for the JTextPane

	JTextPane TextPane1 = new JTextPane();

	//The below two command lines creates instances for fonts

	SimpleAttributeSet sas = new SimpleAttributeSet();

	StyleContext sc = new StyleContext();

	//The below command line sets up the variable for font updating

	MutableAttributeSet mas;

	//The below command line is the default document class which 
	//has one argument as explained below
	//The first argument sets the Style Context of the styled document

	DefaultStyledDocument dse = new DefaultStyledDocument(sc);
	StyledEditorKit StyledEditorKit1 = new StyledEditorKit(); 

	CellPaneRenderer CellPaneRenderer1 = new CellPaneRenderer();
	//end

	public void initialize ()
	{ 
		Container pane = fr.getContentPane();
		pane.setLayout(new FlowLayout());
		fr.setSize(250,300);
		fr.setLocation(300,300);
		fr.setBackground(Color.lightGray);
		//The below command line must be set to false so that user 
		//resizing is allowed

		Table1.setAutoCreateColumnsFromModel(false);
		Table1.setGridColor(Color.black);

		Size1.width = 350;
		Size1.height = 250;
		ScrollPane1.setPreferredSize(Size1);

		Table1.setModel(TableModel1);
		Table1.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
		Table1.setAutoResizeMode(JTable.AUTO_RESIZE_OFF); 

		Table1.setDefaultRenderer(Object.class, new
CustomTableCellRenderer(Color.white));
		Table1.setDefaultRenderer(Object.class, new CellPaneRenderer());

		pane.add(ScrollPane1);
		pane.add(Button1);
		pane.add(Button2);
		combofontfamilyinitialize();
		pane.add(ComboBox1);

		fr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		Button1.addActionListener(this);
		Button2.addActionListener(this);

		ComboBox1.addItemListener(this);
		fr.pack();
		fr.setVisible(true);
	}

	public void combofontfamilyinitialize ()
	{
		//This function fills the combo box with the system available font
families

		GraphicsEnvironment ge1 =
GraphicsEnvironment.getLocalGraphicsEnvironment();
		String[] k = ge1.getAvailableFontFamilyNames();
		ComboBox1= new JComboBox(k);
	}


	public void setAttributeSet(AttributeSet attr)
	{

		//This function only set the specified font set by the
		//attr variable to the text selected by the mouse

		int xStart, xFinish, k;

		xStart = TextPane1.getSelectionStart(); 
		xFinish = TextPane1.getSelectionEnd();
		k = xFinish - xStart; 

		if(xStart != xFinish)
		{
			dse.setCharacterAttributes(xStart, k, attr, false);
		}

		else if(xStart == xFinish)
		{
			//The below two command line updates the JTextPane according to what
			//font that is being selected at a particular moment

			mas = StyledEditorKit1.getInputAttributes();
			mas.addAttributes(attr);
		}

	}

	public void insertcolumn (JTable table2)
	{
		//This function adds a column dynamically to the end of the JTable

		TableModel1 = (DefaultTableModel)table2.getModel();
		TableColumn col = new TableColumn(TableModel1.getColumnCount());

		//add
		col.setCellRenderer(CellPaneRenderer1);
		//end

		TableModel1.addColumn("   ");
		//The below command line adds the new column to the JTable

		table2.addColumn(col);

		TableModel1.fireTableStructureChanged();
	}

	public void actionPerformed(ActionEvent event)
	{
		JComponent b = (JComponent)event.getSource();
		int d;
		String str3 = null;
		String str4 = null, str5 = null;
		Object Object1 = null;
		Object Object2 = null;

		if(b == Button1)
		{
			//The below command line removes the cell editor of the JTable to
			//prevent any repitation of data from being added to the JTable

			Table1.removeEditor();

			insertcolumn(Table1);
		}

		else if(b == Button2)
		{
			//The below command line removes the cell editor of the JTable to
			//prevent any repitation of data from being added to the JTable

			Table1.removeEditor();

			//The below two command lines creates and adds an empty object
			//an a row into the current JTable

			Object[] v = new Object[0];
			TableModel1.addRow(v);
		}

	}
	public void itemStateChanged(ItemEvent event) 
	{
		JComponent c = (JComponent)event.getSource();
		boolean d;

		if(c == ComboBox1)
		{
			Table1.editCellAt(0,0);
			FontFamily = (String)ComboBox1.getSelectedItem();
			TextPane1 = (JTextPane)Table1.getEditorComponent();

			if(TextPane1 != null)
			{
				StyleConstants.setFontFamily(sas, FontFamily);
				setAttributeSet(sas);
			}

		}

	}

	public static void main(String args[])
	{
		TabTest a = new TabTest(); 
		a.initialize();
	}
}

class CellPaneRenderer extends JTextPane implements TableCellRenderer 
{


	public CellPaneRenderer() 
	{

	}

	public Component getTableCellRendererComponent(JTable table, Object
value, 
	boolean isSelected, boolean hasFocus,
	int row, int column) 
	{

		setText((String)value);
		setSize(table.getColumnModel().getColumn(column).getWidth(),
getPreferredSize().height);

		if(table.getRowHeight(row) != getPreferredSize().height) 
		{
			table.setRowHeight(row, getPreferredSize().height);
		}

		return this;

	}

}

Why this exception is occurring i am not very sure and really hope someone
can help me with this problem.

Any help is greatly appreciated

Thank You

Yours Sincerely

Richard West

freesoft_2000 <freesoft_2000@yahoo.com> wrote:

>                     I am currently trying to use a JTextPane as a cell
> renderers for a JTable but it does not seem to work although the program
> compiles. I alsways get an error stating class cast exception saying that
> i must cast the editor component to JTextField instead of a JTextPane
> although i am using a JTextPane as a cell renderer.

Editor != Renderer

Your general logic is also not clear: Changing the font of the editor
will not have any permanent effects unless the font change is actually
stored somewhere permanently (If it is supposed to be part of the data to
be edited, in the TableModel).


>                     Below is a small compilable that i have done which
> compiles and throws the exception that i have mentioned about

It is not directly compilable: The unused class CustomTableCellRenderer
is missing, and your newsreader has wrapped lines so that comments have
become code.


Christian

Hi everyone,

I tried writing and using the below code by extending the
DefaultCellEditor class and uisng it but it only got worse as now if i
apply the font to the selected text in the cell all the text dissapears

Here is the code of the class theat extends the default cell editor class

class CellPaneEditor extends DefaultCellEditor 
{

JTextPane TextPane1 = new JTextPane();
StyleContext sc = new StyleContext();
DefaultStyledDocument dse = new DefaultStyledDocument(sc);
StyledEditorKit StyledEditorKit1 = new StyledEditorKit(); 
        
public CellPaneEditor() 
{
super(new JTextField());
TextPane1.setEditorKit(StyledEditorKit1);
TextPane1.setDocument(dse);
}

public Component getTableCellEditorComponent(JTable table, Object value, 
                                             boolean isSelected,int row, 
                                             int column) 
{
return TextPane1;
}

}

Here is the entire code using the above class which compiles

import java.awt.*;
import java.awt.image.*;
import java.io.*;
import java.text.*;
import java.awt.event.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;
import javax.swing.text.*;

public class TabTest implements ActionListener, ItemListener

{

JFrame fr = new JFrame ("Frame");


JButton Button1 = new JButton("Add Coloum");
JButton Button2 = new JButton("Add Row");

JComboBox ComboBox1;

DefaultTableModel TableModel1 = new DefaultTableModel(0, 0);

JTable Table1 = new JTable(TableModel1);

JScrollPane ScrollPane1 = new JScrollPane(Table1,
ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS, 
                                         
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);  
                                          
String FontFamily = "Arial";

Dimension Size1 = new Dimension();

//add
//The below command line is the constructor for the JTextPane

JTextPane TextPane1 = new JTextPane();

//The below two command lines creates instances for fonts

SimpleAttributeSet sas = new SimpleAttributeSet();

StyleContext sc = new StyleContext();

//The below command line sets up the variable for font updating

MutableAttributeSet mas;

//The below command line is the default document class which 
//has one argument as explained below
//The first argument sets the Style Context of the styled document

DefaultStyledDocument dse = new DefaultStyledDocument(sc);
StyledEditorKit StyledEditorKit1 = new StyledEditorKit(); 
//end

public void initialize ()
{ 
Container pane = fr.getContentPane();
pane.setLayout(new FlowLayout());
fr.setSize(250,300);
fr.setLocation(300,300);
fr.setBackground(Color.lightGray);
//The below command line must be set to false so that user 
//resizing is allowed

Table1.setAutoCreateColumnsFromModel(false);
Table1.setGridColor(Color.black);

TextPane1.setEditorKit(StyledEditorKit1);
TextPane1.setDocument(dse);

Size1.width = 350;
Size1.height = 250;
ScrollPane1.setPreferredSize(Size1);

Table1.setModel(TableModel1);
Table1.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
Table1.setAutoResizeMode(JTable.AUTO_RESIZE_OFF); 

Table1.setDefaultEditor(Object.class, new CellPaneEditor());

pane.add(ScrollPane1);
pane.add(Button1);
pane.add(Button2);
combofontfamilyinitialize();
pane.add(ComboBox1);

fr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Button1.addActionListener(this);
Button2.addActionListener(this);

ComboBox1.addItemListener(this);
fr.pack();
fr.setVisible(true);
}

public void combofontfamilyinitialize ()
{
//This function fills the combo box with the system available font
families

GraphicsEnvironment ge1 =
GraphicsEnvironment.getLocalGraphicsEnvironment();
String[] k = ge1.getAvailableFontFamilyNames();
ComboBox1= new JComboBox(k);
}


public void setAttributeSet(AttributeSet attr)
{

//This function only set the specified font set by the
//attr variable to the text selected by the mouse
 
int xStart, xFinish, k;

xStart = TextPane1.getSelectionStart(); 
xFinish = TextPane1.getSelectionEnd();
k = xFinish - xStart; 

if(xStart != xFinish)
{
dse.setCharacterAttributes(xStart, k, attr, false);
}

else if(xStart == xFinish)
{
//The below two command line updates the JTextPane according to what
//font that is being selected at a particular moment

mas = StyledEditorKit1.getInputAttributes();
mas.addAttributes(attr);
}

}

public void insertcolumn (JTable table2)
{
//This function adds a column dynamically to the end of the JTable
 
TableModel1 = (DefaultTableModel)table2.getModel();
TableColumn col = new TableColumn(TableModel1.getColumnCount());

TableModel1.addColumn("   ");
//The below command line adds the new column to the JTable

table2.addColumn(col);
 
TableModel1.fireTableStructureChanged();
}
     
public void actionPerformed(ActionEvent event)
{
JComponent b = (JComponent)event.getSource();
int d;
String str3 = null;
String str4 = null, str5 = null;
Object Object1 = null;
Object Object2 = null;

if(b == Button1)
{
//The below command line removes the cell editor of the JTable to
//prevent any repitation of data from being added to the JTable

Table1.removeEditor();

insertcolumn(Table1);
}

else if(b == Button2)
{
//The below command line removes the cell editor of the JTable to
//prevent any repitation of data from being added to the JTable

Table1.removeEditor();

//The below two command lines creates and adds an empty object
//an a row into the current JTable

Object[] v = new Object[0];
TableModel1.addRow(v);
}

}
public void itemStateChanged(ItemEvent event) 
{
JComponent c = (JComponent)event.getSource();
boolean d;

if(c == ComboBox1)
{
Table1.editCellAt(0,0);
FontFamily = (String)ComboBox1.getSelectedItem();
TextPane1 = (JTextPane)Table1.getEditorComponent();

if(TextPane1 != null)
{
StyleConstants.setFontFamily(sas, FontFamily);
setAttributeSet(sas);

Button1.setText("Received");
}

}

}

public static void main(String args[])
{
TabTest a = new TabTest(); 
a.initialize();
}
}

class CellPaneEditor extends DefaultCellEditor 
{

JTextPane TextPane1 = new JTextPane();
StyleContext sc = new StyleContext();
DefaultStyledDocument dse = new DefaultStyledDocument(sc);
StyledEditorKit StyledEditorKit1 = new StyledEditorKit(); 
        
public CellPaneEditor() 
{
super(new JTextField());
TextPane1.setEditorKit(StyledEditorKit1);
TextPane1.setDocument(dse);
}

public Component getTableCellEditorComponent(JTable table, Object value, 
                                             boolean isSelected,int row, 
                                             int column) 
{
return TextPane1;
}

}

Why the JTable is reacting in this way i am not sure and hope someone can
point out to me why this is happening.

Sorry about the code not compiling earlier to a careless mistake of mine.
Sorry about it

Thank You

Yours Sincerely

Richard West

freesoft_2000 <freesoft_2000@yahoo.com> wrote:

> I tried writing and using the below code by extending the
> DefaultCellEditor class and uisng it but it only got worse as now if i
> apply the font to the selected text in the cell all the text dissapears

You are missing setText() in the editor. Also, do not use DefaultCell-
Editor.


[...]

> if(b == Button1)
> {
> //The below command line removes the cell editor of the JTable to
> //prevent any repitation of data from being added to the JTable

> Table1.removeEditor();

'removeEditor' should not be called and is probably accidentally public. Use

TableCellEditor c = table.getCellEditor();

if (c != null)
    if (!c.stopCellEditing())
         c.cancelCellEditing();



Christian