How to reset a JTable - java

I have a question with respect to JScrollPane and a JTable.
I have added a JTable to a JScrollPane, and added the JScrollPane to the JPanel. When I click on 'show' button, the JTable will be filled with contents from the database.
I also have another button reset, clicking on which will remove the contents of the JTable, and the JScrollPane. It is supposed to be doing that, but what happens is that, even after clicking the button, all the contents of the JTable and the JScrollPane still exists.
I used revalidate(), reinstantiate(), etc, but of no use. How do I make it work?

Assuming you are using a DefaultTableModel, then you just do:
model.setRowCount(0);

In order to remove a row from a JTable, you need to remove the target row from the underlying TableModel. If, for instance, your TableModel is an instance of DefaultTableModel, you can remove a row by doing the following:
((DefaultTableModel)myJTable.getModel()).removeRow(rowToRemove);
Updation 2
To know the rows and delete from jtable
int rows = myJTable.getRowCount();
for(int i=0;i<rows;i++)
((DefaultTableModel)myJTable.getModel()).removeRow(i);

Related

Changing Content of JTable Cells Individually

So Suppose I create a JTable with a specific number of columns and rows. Is it possible to add a JPanel to a specific cell after the JTable is already initialized? The JTable would be empty at first and then I would change a cell at row X and column Y to instead contain a JPanel which would contain an amount of ImageIcons. I don't have any code to put here really, I just need to know what I would have to use to accomplish this and how. Thank you.
To change the data in the table you use:
table.setValueAt(...);
This will update the data in the TableModel.
However, adding a JPanel to the table is not the way a table is designed to be used. Typically you add data to the model. Then you use a renderer to display the data in a cell.
Start by reading the section from the Swing tutorial on Using Custom Renderers for more information and examples.

Edit JTable in Netbeans Builder

I designed a JTable with Netbeans Builder and I created 5 columns, the 5th one is Boolean so I want to know how to highlight whole the row when the user selected.
See Table Row Rendering for an easy way to color an entire row based on a value in the row.
The problem now is that only the cell is automatically repainted when you click on the checkbox so you will also need to add a TableModelListener to the TableModel so you can invoke a repaint() on the table row whenever the state of the checkbox is changed.

Insert/add data to JTable & Database using a popup frame after clicking the "add" button

May I know how do I make a popup frame to do the insert of data since I'd like my GUI to popup another frame to ask for user input to the database and as well as the JTable? Thank you!
What I don't get is how to make use of the add button, then insert the entry and make the listener notice about "e.getType()==TableModelEvent.INSERT".
Edit:
At the same panel as the JTable, I would have an add button at the bottom. This add button would then in another 'frame' ask users to enter the items to add to the database as well as adding and refreshing the JTable.
you must use a DataModel with your JTable, and add item to your datamodel and then update your JTable with yout DataModel.
DefaultTableModel model = new DefaultTableModel();
JTable table = new JTable(model);
// Create a couple of columns
model.addColumn("Col1");
model.addColumn("Col2");
// Append a row
model.addRow(new Object[]{"v1", "v2"});
inserting new data from external class into jtable
Have a look at this , I hope your problem will be solved , Pass the Table reference in the constructor of your JFame/JDialogue (Better if you use JDialogue Instead of JFrame click here to know some good reasons) and modify table model accordingly

Display values of a selected row from a dynamically varying JTable

I have to develop a front end in Swing.I have a JFrame in Netbeans with 3 panes in it.
JScrollPane 1:it contains a JTable
JScrollPane 2: It should display the value of the fields of the selected row
ListPane : which contains the list of tables from which a user chooses a table to be displayed.
Now since the content of JTable varies(the no of rows and columns also vary) dynamically based on the table chosen by user I can't drag and drop the TextBoxes in the 3rd scroll pane to display the selected row's values.It would be helpful if anybody can suggest a way to do it or any pointers to problems that deal with similar issue
Add a ListSelectionListener to your JList. When a particular table is selected from the list, use setModel() to change the TableModel of your JTable to one that is correct for the chosen table. A related example using setModel() is shown here.

Clearing a JScrollPane but can't then 'attach' tables

I am creating an application where I have 3 Panes with buttons which dynamically create buttons in the next pane depending on the selection, clicking the last button shows a table of data brought up via an SQL query:
[buttonPane1][buttonPane2][buttonPane3][table]
If a user has clicked a button on all 3 panes and then wants to change their choice on buttonpanel1, it will bring up the choices in buttonpanel2 and using
buttonPanel3.removeAll();
buttonPanel3.repaint();
I can clear the third button panel, my problem is how to clear the table. I want to remove it from the Table ScrollPanel however if I try
tableScrollPanel.removeAll();
it just means that the table never shows.
How can I remove any current table but allow a table to be 'reattached' I am doing this to create and 'attach' the table
jTableTemp.setModel(new DefaultTableModel(
tableContent, tableTitles));
tableScrollPanel.setViewportView(jTableTemp);
Thanks Very Much
Try setting the table model to a DefaultTableModel with empty data and the original headers, then repaint. As long as you have a JScollPane wrapped around the JTable, the headers should show up, assuming this is what you want.
Other wise, you can set the viewport to a new instance of a JTable with new headers.

Categories