JTable setRowSelectionInterval has no effect for JButton - java

Using a JTable, my Table Model setValueAt() method moves the selection to the next row in certain cases, using setRowSelectionInterval() and setColumnSelectionInterval(). When it's called from the (default) cell editor (by user typing in the cell and hitting tab), the code works: the desired next cell is selected (the first one on the next row).
However, if the user uses Return rather than Tab to commit the edit, the selection doesn't happen; instead the cell below is selected. That's fine with me.
I also have a JButton to clear a row. The button's action function calls the model's setValueAt() function for the desired cells. Unfortunately, the setRowSelectionInterval() and setColumnSelectionInterval() methods have no apparent effect; instead, no cells are selected.
I've tried table.requestFocusInWindow() and table.getParent().requestFocusInWindow(), as well as table.changeSelection(row, 0, false, false), all to no apparent effect.
Is there anything basic I'm missing here, before I go to the trouble of building the SSCCE?
In case it matters, here's the container hierarchy:
parent JPanel
button rows JPanel
button row 1 JPanel
button row 2 JPanel
table JScrollpane
JTable
The button in question is in button row 1.
Thanks!

Maybe you can use the Table Cell Listener to listen for edits to the table. It listens for actual changes done by the JTable editor.
Then in the supplied Action you can select the appropriate row. You may need to wrap the Action code in a SwingUtilities.invokeLater(...) to make sure the code executes after the table is completely finished editing.

Related

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.

JTable cell value passed to textarea on single click

On my form I have a jtable and a textarea. My table only has 2 columns - ID and Comment
Is it possible that when a user clicks on a cell in the comment column. The cell value will appear in the textarea in edit mode?
I did set the cell editor to singleclick
selectTable.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
TableColumn col = selectTable.getColumnModel().getColumn(1);
DefaultCellEditor singleclick = new DefaultCellEditor(new JTextField());
singleclick.setClickCountToStart(1);
col.setCellEditor(singleclick);
I have a method outputSelection() that gets called from a edit button. The method gets the value from the selected cell and puts the value in the textarea for edit.
Can the click activate the method so the user does not have to click a edit button?
You could attach a mouse listener to the table and monitor the mouse clics from there, getting the selected column/row & thus the value
You could supply your own cell editor that updates the text area when the editors value is set
You could extend te jtable & when cell editing is started, update the text area
Yes, this is a process I learned to use after having duplicate code throughout my swing application. I started making standalone methods that did the work I wanted, and then I call those methods from the action events from the button or mouse click. That way they all execute the same code.
Even if you have a tab or enter key command, you can also have it execute your same method as the others for more consistent code.
If your button performs specific code with cell values, just extract all of that code out into a method that takes the cell value as input. Then you can call that same method from any event and pass in the input data you want to display in the text area.

java : when is this method called : getTableCellRendererComponent?

In order to set the color for a specific table cell, I should create a custom TableCellRenderer which has the following method : getTableCellRendererComponent.
when is this method called : getTableCellRendererComponent ?
just when a JTable is drawn for the first time ?
In case I have a set of buttons and a jtable on a jframe, and each button when pressed will cause a certain number of cells in the table to be colored, how can I cause this method "getTableCellRendererComponent" to be called when I press on the button ?
This is fired when the table is first rendered but should be called on all cells when either a fireTableCellUpdated or any of the other "fire*" methods are called. I'm under the impression that you're using a class that extends AbstractTableModel (DefaultTableModel?) at which point these methods should be fired when you update a particular value of a table model.
An example of using custom cell renderers can be found at Example Depot. The getTableCellRendererComponent will be called when a cell is brought in to view and when a model update occurs.
Addendum: I just noticed one other part to your question, when is the getTableCellRendererComponent called? This is called for every visible cell in the table that must be rendered. Think of it this way, if you are using a JLabel internally as your renderer, you would return the JLabel as configured for displaying that cell only. It will be reused on the next cell for rendering it. Easiest way to think of it is a visual template that you want your cell to look like, you configure it on the getTableCellRendererComponent call, and return it. The calling framework renders it to the screen buffer as an "image" (for lack of a better term) then is reconfigured for the next cell and rendered again.
if you want to forgot for when/how/where is/are TableCell(s) updated or not then look for prepareRenderer best example as I see camickr blog
EDIT: for better/valuable hepl please edit your post and add your code
when is this method called :
getTableCellRendererComponent ?
This method will get called when the UI component gets displayed/rendered for your view the very first time.
To set colors in cells of a JTable
Hope you are using the custom DefaultTableCellRenderer. If so, then you can globalize the JLabel in your custom CellRenderer and then set its background color upon button click based on the row, column index.
Else you can use the DefaultTableColumnModel which you have defaultrenderer/set customrenderer which will be renderered for each of the cell. Using which you can set the background color of the cell.
TableColumn col = table.getColumnModel().getColumn(vColIndex);
col.setCellRenderer(new MyTableCellRenderer());
Refer: Simple example to demonstrate usage of TableCellRenderer

How to enable using arrows keys to move row selection in JTable?

I noticed that I can you arrows to move row selection of my JTable object only when I press tab key. Is it possible to use arrows after row selection by mouse-click (instead of using TAB)?
In order for the arrow keys to change row selection, the JTable must have focus. Pressing the tab key changes focus to the next (or first) "focussable" Component on the page which is likely a SubComponent in the JTable.
To get it to focus automatically when it becomes visible, add a ComponentListener with the an componentShown(...) method implemented to call the JTable's requestFocusInWindow() method.
Is it possible to use arrows after row selection by mouse-click (instead of using TAB)
Yes; if you click the mouse on a row, that should also focus the row, allowing you to use the arrow keys as well.
Updated: corrected method used to get input focus, with thanks to camickr (see comments)

Add text and icon (with MouseListener) to JTable column

I want to implement following functionality but I am confused if it's possible in Java. If yes, than how? Please help:
I want to create a JTable kind of table where 1st row of table contains column names and an icon in each column i.e. in each cell of 1st row. Clicking on that icon should lead to removal of that column from table (possible using MouseListener??).
I have found many solution where I can add button to a cell in JTable but none which describes adding both text and icon (with MouseListener) to a cell. Please see if you can help and thanks a lot for reading.
You can create a custom TableCellRenderer that extends JLabel. This JLabel can be created with an icon (JLabel can display icons, to the right or left of the text). You will want the getTableCellRendererComponent to test wether the row being rendered is the first or not, and if so, set the icon, otherwise do not.
For the removal action, you can add a MouseListener on the table, and when processing the mouseClicked method, you can find the cell that was clicked in by testing the rowAtPoint and columnAtPoint by creating a Point from the mouseEvent.getX() and mouseEvent.getY(). If you determine the first row with the icon was clicked, you can remove the column from the column model.
If by 1st row, you actually mean the table header, you can create the same renderer for the JTableHeader, and set the MouseListener on that component.
Well, I don't understand your question.
I want to create a JTable kind of
table where 1st row of table contains
column names and an icon
Do you mean the Table Header, like the way sorting works by displaying the column name and the sort direction?
If so then you use a custom renderer for the table header and add a MouseListener to the header to determine which column was clicked. You should be able to customize the Default Table Header Renderer to do what you want.
Or do you mean the first row of data in the table. If so then you still need to use a custom renderer but this time you add the MouseListener to the table not the table header.
In both cases you can use the TableColumnModel.removeColumn() method to remove the column from the view of the table.

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