I have a tree and a table on my panel, when I click the tree node, the table needs to change at the same time, but it doesn't. I search online and read the Java tutorial and didn't find any solutions. From some posts I think I need to use fireTableStruetureChanged(), but it just doesn't work in my code. Could anyone help me out of this? The following is the code. Thanks a ton!
public class tableStructureChange extends JFrame implements ... {
.....
/ //columnNames is a public variable, because I need to change the columns later
columnNames = new String[] {"col1","col2"}; */
data = new String[][]{
{"Mary", "Campione"},
{"Alison", "Huml"}, };
table = new JTable(new MyTableModel());
table.setAutoCreateColumnsFromModel( false );
feedback = new JScrollPane(table); //feedback is the bottom panel
...
}
//the following class is the problem, i need the table to be reloaded
//when the class is called, but the table doesn't change at all
public void displayFeedback(String tempString) {
//create table for bottom panel
columnNames = new String[] {"col3","col4", "col5"};
String[][] data = new String[][]{
{"Mary", "Campione", "us"},
{"Alison", "Huml", "canada"}, };
//table = new JTable(data, columnNames);
//fireTableStructureChanged(); //this is the problem part
}
// my table model
class MyTableModel extends AbstractTableModel {
String[] columnNames = new String[] {"col1","col2"};
public int getColumnCount() {
return columnNames.length;
}
public int getRowCount() {
return data.length;
}
public String getColumnName(int col) {
return columnNames[col];
}
public Object getValueAt(int row, int col) {
return data[row][col];
}
}
...
}
In your method displayFeedback you seem to be hoping to replace the JTable object and have the display change to reflect what is selected in the JTree above. Instead of replacing what is in the View object, you should focus your effort on updating the Model, in this case, the AbstractTableModel subclass that you have created. There are a couple ways you can do that, but for a brute force proof of concept, you could do something like the following:
add a constructor to MyTableModel that takes a 2 dimensional array of data
in displayFeedback, create a new instance of MyTableModel that has new data relevant to the tree node that was selected.
call setModel on your global table variable.
Related
I created a class that is meant to show a JTable populated with data taken from a database with hibernate:
public class FLlistes extends JInternalFrame {
private JTable table;
private DefaultTableModel model;
//some code for more components of the form
String[] columns = {"Id","Data", "Lloc"};
model = new DefaultTableModel(columns, 0) {
#Override
public Class<?> getColumnClass(int columna) {
if (columna == 2)
return LocalDate.class;
return Object.class;
}
#Override
public boolean isCellEditable(int row, int column) {
return false;
}
};
table = new JTable(model);
JScrollPane scrollPane = new JScrollPane();
scrollPane.setBounds(49, 176, 732, 361);
getContentPane().add(scrollPane);
scrollPane.setViewportView(table);
//some code for more components of the form
}
Then I have a class that makes the queries with hibernate. The next method is supposed to collect data from a table and populate the table I created before.
public class AccionsBD {
public static void GetAllLlistes() {
String jql = "select llc from LlistaCompra llc";
EntityManager entityManager = JPAUtil.getEntityManagerFactory().createEntityManager();
TypedQuery<LlistaCompra> q = entityManager.createQuery(jql,LlistaCompra.class);
List<LlistaCompra> llistes = q.getResultList();
FLlistes fl = new FLlistes();
for (LlistaCompra llista: llistes) {
System.out.println(llista.getIdLlista());
System.out.println(llista.getData());
System.out.println(llista.getLloc());
Object[] objFila = new Object[3];
objFila[0] = llista.getIdLlista();
objFila[1] = llista.getData();
objFila[2] = llista.getLloc();
fl.getModel().addRow(objFila);
}
entityManager.close();
}
}
The purpose of the System.out.println inside the loop is only to check that the query works. The query is working fine, I tried debugging and the end of the loop objFila contains all the correct data, but the table in the form never shows anything besides the table header. What am I missing?
Also, for some reason sometimes when I run the app the form shows up, and somtimes it doesn't. It does this without even changing the code. Why does this happen?
Edit: this is my getter:
public DefaultTableModel getModel() {
return model;
}
What I am trying to do is to populate a JTable from an ArrayList.
The array list is a type Record which I have defined below:
public class Record {
int Parameter_ID;
int NDC_Claims;
int NDC_SUM_Claims;
public Record(int parameter, int claims, int ndc_sum_claims){
Parameter_ID = parameter;
NDC_Claims = claims;
NDC_SUM_Claims = ndc_sum_claims;
}
public Record() {
// TODO Auto-generated constructor stub
}
I don't know how to populate the table with the column headers as well. This is what I have so far:
DefaultListModel listmodel = new DefaultListModel();
ArrayList<Record> test = new ArrayList<Record>();
DefaultTableModel modelT = new DefaultTableModel();
Object data1[] = new Object[3];
for(int i=0; i<test.size();i++){
data1[0] = test.get(i).Parameter_ID;
data1[1] = test.get(i).NDC_SUM_Claims;
data1[2] = test.get(i).NDC_Claims;
modelT.addRow(data1);
}
table_1 = new JTable(modelT, columnNames);
contentPane.add(table_1, BorderLayout.CENTER);
contentPane.add(table_1.getTableHeader(), BorderLayout.NORTH);
Nothing is outputted. Any help would be great!
Well you need to start by reading the API. You can't program if you don't read the API first.
DefaultTableModel modelT = new DefaultTableModel();
When you read the API what does that constructor do? It creates a model with 0 rows and 0 columns. You will want to create a model with 3 columns and 0 rows so that you can add rows of data to the model. Read the DefaultTableModel API
table_1 = new JTable(modelT, columnNames);
What does that statment do? I don't see a constructor that allows you to specify a model and column names so how does your code compile. You just want to create the table using
the model.
contentPane.add(table_1, BorderLayout.CENTER);
contentPane.add(table_1.getTableHeader(), BorderLayout.NORTH);
The table should be added to the viewport of a JScrollPane. The header will then be displayed as the column header of the scroll pane.
Read the JTable API. The API also has a link to the Swing tutorial on How to Use Tables you need to read for the basics.
ArrayList<Record> test = new ArrayList<Record>();
You create an empty ArrayList. So what do you expect to happen when you iterate through the loop? How can you add data to the model if there is no data in the ArrayList?
Also, did you search the forum/web for examples that use the DefaultTableModel or JTable classes. Those examples will help you write your code.
You can create a custom AbstractTableModel and then create a JTable using that model.
Here is a class handling ArrayList of Arrays:
import java.util.ArrayList;
import javax.swing.table.AbstractTableModel;
public class DataTableModel<T> extends AbstractTableModel {
/**
* Benjamin Rathelot
*/
private static final long serialVersionUID = -7361470013779016219L;
private ArrayList<T[]> data = new ArrayList<T[]>();
private String[] tableHeaders;
public DataTableModel(ArrayList<T[]> data, String[] headers) {
super();
this.data = data;
this.tableHeaders = headers;
}
#Override
public int getRowCount() {
return data.size();
}
#Override
public int getColumnCount() {
if(data.size()>0) return data.get(0).length;
return 0;
}
#Override
public Object getValueAt(int arg0, int arg1) {
// TODO Auto-generated method stub
if(data.size()>=arg0) {
if(data.get(arg0).length>=arg1) {
return data.get(arg0)[arg1];
}
}
return null;
}
#Override
public String getColumnName(int columnIndex) {
return tableHeaders[columnIndex];
}
}
This question already has an answer here:
Store products in a TreeSet and print the content in a JTable
(1 answer)
Closed 7 years ago.
I'm trying to display a single JTable, but I keep getting many new JTables everytime I insert a new product: http://i.stack.imgur.com/gyNsn.png
How can I display just one JTable and also make the column names visible?
Here is the method that creates the table:
public JTable populate(Product p) {
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
Vector<Object> row = new Vector<Object>();
Vector<String> headers = new Vector<String>();
headers.add("Product name");
headers.add("Price");
headers.add("In stock");
row.add(p.getProductName());
row.add(p.getPrice());
row.add(p.getStock());
data.add(row);
productsTable = new JTable(data, headers);
return (new JTable(data, headers));
}
And here is a part from the GUI class:
addProductBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Product product = new Product(insertProductName.getText(), Integer.parseInt(insertPrice.getText()), Integer.parseInt(insertStock.getText()));
warehouse.addProduct(product); // by using a TreeSet
productsTable = warehouse.populate(product); // here I call the earlier defined method
warehouse.initFile(); // I wrote the productsTable content into a binary file, so that it can act like a database
warehouse.readFile();
warehouse.populate(product);
manageProductsPanel.add(productsTable);
});
The populate method you posted creates a new JTable every time it is called. Given this is called every time the ActionListener is called, a new JTable will be added. You should consider creating your own TableModel - extend AbstractTableModel and override the necessary methods, returning the appropriate values for each row/column. A simple example is below, making some assumptions about project structure for demo's sake (for instance warehouse is an instance of a List):
public class MyTableModel extends AbstractTableModel{
#Override
public int getColumnCount() {
return 3;
}
#Override
public int getRowCount() {
return warehouse.size();
}
#Override
public Object getValueAt(int arg0, int arg1) {
switch(arg1){
case 0:
return warehouse.get(arg0).getName();
case 1:
return warehouse.get(arg0).getPrice();
default:
return warehouse.get(arg0).isInStock();
}
}
#Override
public String getColumnName(int col){
switch(col){
case 0:
return "Name";
case 1:
return "Price";
default:
return "In STock";
}
}
}
You can then create an instance of this class, and set the table model for the JTable. Every time the backed List is updated, you can update the Listeners of the TableModel
MyTableModel tableModel = new MyTableModel();
myTable.setMOdel(tableModel);
.......
//when an item is added to
warehouse.add(item);
tableModel.fireTableDataChanged();
There are more demonstrations for how to customize a JTable in the Oracle Tutorials
I want to add data to my own JTable model in runtime. I have the table and add button on my interface. As I understand I cant do it with two dimensional array and want to use Arraylist in my custom made table model but I dont know how to make the constructor if I use such type of data.
static String[] columnNames = {"A", "B", "C"};
static Object data[][] = new Object[15][3];
public MyTableModel() {
super(data, columnNames);
}
this is the constructor for data as two dimansional array but I want to use:
ArrayList<Object[]> data = new ArrayList<Object[]>();
How to make it
One way to do it, is to use AbstractTableModel. Here is an example:
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.AbstractTableModel;
public class TestTable {
public static class MyModel extends AbstractTableModel {
private List<Object[]> data;
private List<String> columnNames;
public MyModel(List<String> columnNames, List<Object[]> data) {
super();
this.columnNames = columnNames;
this.data = data;
}
#Override
public int getRowCount() {
return data.size();
}
#Override
public int getColumnCount() {
return columnNames.size();
}
#Override
public String getColumnName(int column) {
return columnNames.get(column);
}
#Override
public Object getValueAt(int rowIndex, int columnIndex) {
return data.get(rowIndex)[columnIndex];
}
}
protected void initUI() {
JFrame frame = new JFrame(TestTable.class.getSimpleName());
List<String> columns = Arrays.asList("Name", "Age");
List<Object[]> data = new ArrayList<Object[]>();
for (int i = 0; i < 50; i++) {
Object[] value = new Object[2];
value[0] = "Name-" + i;
value[1] = 12 + i;
data.add(value);
}
JTable table = new JTable(new MyModel(columns, data));
frame.add(new JScrollPane(table));
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new TestTable().initUI();
}
});
}
}
If you need to to modify your data List<Object[]>, don't forget to fire appropriate Table Events. AbstractTableModel contains them all already.
It's a bit hard to tell what you're doing as you haven't included the full source code of your table model, so I'm going to make a few assumptions here.
You're probably either extending AbstractTableModel or DefaultTableModel. In either case, you shouldn't have to add your data to the model via the constructor. Instead, you will want to override the following methods in your TableModel extension:
getRowCount()
getColumnCount()
getValueAt(int row, int column)
Make it so that each of these methods indexes into your ArrayList<Object[]> data object - e.g., getValueAt(row,column) should return something like data.get(row)[column]. Then add your TableModel to a JTable and you should be good to go, as far as displaying the custom data goes.
Now... when your data changes (either you changed the value of a cell in the table or you added/removed rows), you just call fireTableDataChanged() on your TableModel (assuming it has extended AbstractTableModel or one of its subclasses). This will force the UI to update with the changes you made to the underlying data.
The most straightforward way to create your own table model is to inherit from AbstractTableModel. Then override, at a minimum, getRowCount, getColumnCount, and getValueAt.
You can then either create the table using "new JTable(mymodel)", where "mymodel" is an instance of the model you have created, or you could create it with just "new JTable", and then later do setModel to attach your model to the JTable.
For example -- and while I've done this a bazillion times, I'm writing this off the top of my head so no warranties expressed or implied, odds are there's a syntax error or two in there somewhere:
class ArrayListModel extends AbstractTableModel
{
ArrayList<Object[]> list;
public ArrayListModel(ArrayList<Object[]> list)
{
this.list=list;
}
public int getRowCount()
{
return list.size();
}
public int getColumnCount()
{
if (list.size()==0)
{
return 0;
}
else
{
return list.get(0).length;
}
}
public Object getValueat(int row, int column)
{
return list.get(row)[column];
}
}
... somewhere else ...
ArrayListModel mymodel=new ArrayListModel(somedata);
JTable mytable=new JTable(mymodel);
... etc ...
Side note: When I was first learning Java, I thought that the "normal" way to create a JTable was to use the default model, create a vector of vectors or a 2-D array and then populate. I thought creating your own model would be something you did in rare, odd cases. But I've since figured out that the default model is only the best way in rare, simple cases. Now I almost always create my own model: it's usually easier to code and easier to understand. Typically I have an ArrayList of some class that I've created with specific fields, and then in my model class I have something like:
public Object getValueAt(int row, int col)
{
Whatever w=list.get(row);
if (col==0) return w.foo;
else if (col==1) return w.bar;
else if (col==2) return w.plugh;
else throw SomeException();
}
Or use a case statement. Same idea.
I created a Java GUI that displays the table using the following syntax:
table = new JTable(new MyTableModel(columnNames,
updateTable(cmbAdversary.getSelectedItem().toString(),
cmbdataType.getSelectedItem().toString())));
where columnNames is a Vector of Strings
cmbadversary and smbdataType are the selection od combo boxes.
and updateTable is a method that returns a Vector of Vectors depending on the combo box selection as follows:
static Vector updateTable(String FilterVal1 , String FilterVal2)
{
try {
myVector = tssc.testSeverityFunctionService(FilterVal1,FilterVal2);
} catch (Exception e) {
e.printStackTrace();}
return myVector;
}
This is how my custom class MyTableModel that extends AbstractTableModel looks like:
class MyTableModel extends AbstractTableModel
{
Vector columnNames = new Vector();
Vector Fdb = new Vector();
public MyTableModel(Vector cName,Vector rName){
this.columnNames = cName;
this.Fdb = rName;}
public int getColumnCount() { // number of columns in the model.
return columnNames.size();
}
public int getRowCount() { // number of rows in the model.
return Fdb.size();
}
#Override
public String getColumnName(int col) {
return columnNames.get(col).toString();
}
public Object getValueAt(int row, int col) {
Vector v = (Vector) this.Fdb.get(row);
return v.get(col);
}
#Override
public Class getColumnClass(int c) {
Vector v = (Vector) Fdb.get(0);
return v.get(c).getClass();}
public boolean isCellEditable(int row, int col)
{ return true; }
public void setValueAt(Vector value, int row, int col)
{
for(int i=0;i<value.size();i++)
{ for(int j=0;j<columnNames.size();j++) {
Fdb.setElementAt(value.get(j),j); }
}
fireTableCellUpdated(row, col);
}
}
The problem is that when I run the code, the table GUI show me initial values but fails to update when I change the selection in the 2 comboboxes and click the selection button.
The Selection button, btw, calls a method which implements the action listener.
Please help me out. Am no pro in Java, but willing to learn. If you have any followup qs., I'll be happy to provide details.
Your solution seems overly complicated. If I understand the basics, the user chooses a value from a combo box, then based on the selection some data is loaded into the table.
There is no need to create a custom table model to do this.
A TableModel contains data. If you want to change the data, then one way to do this is to simply create a new TableModel. So you add an ActionListener to your combo box. When an item is selected you retrive your data and load the data into an Vector or an Array. Using this data you can create a new TableModel and update the JTable in two lines of code:
DefaultTableModel model = new DefaultTableModel(...);
table.setModel( model );
If you need to customize the model to override the getColumnClass() or isCellEditable() methods, then you should extend the DefaultTableModel. I don't see any need to implement the whole model.