How would I resize the column for it to just fit the largest string in that column. For example in one column I might have a word like "Monday" and I want this column to be shorter than the "Wednesday" column.
The data changes often as it shows the next 3 days, so I would want Java to automatically change it depending on the input data rather than me having to manually set the column width.
My JTable is within a JScrollPane if that changes anything
Hope that makes sense. Please point me in the right direction.
Related
I have the following code snippet.
int index = getEventList().indexOf(myObj);
SelectionLayer selectionLayer = getGlazedListsGridLayer()
.getBodyLayerStack().getSelectionLayer();
getNatTable().repaintCell(0,selectionLayer.getRowIndexByPosition(index));
When I run the code shown above, the affected cells only get repainted after I click on the table displayed in the GUI. If I comment out that code and use getNatTable().refresh(); it repaints without me having to first click on the table.
Is there a way to have a cell repainted without having to click on the table displayed in the GUI? I would hate to have to call refresh() for a large table where this code may be executed many times.
No you don't need to perform some additional step in order to trigger the repainting. The issue in your code is the usage of wrong index values. You have a grid so column 0 is the row header from the NatTable perspective. I suppose you want to redraw the first column of the body, which is index 1 from the NatTable point of view. Also the row index is incorrect, as you calculate the index in the SelectionLayer but actually need the index in the table, which is at minimum +1 if you only have a column header row.
Actually your code should work by adding 1 on the index if you have one row header column and one column header row in the grid.
getNatTable().repaintCell(1, selectionLayer.getRowIndexByPosition(index) + 1);
I want to be able to do two things:
set colors of rows based on index, so first row is red, second blue,
third green
be able to set color of columns also based on something, be it index
or their names etc, whatever is possible.
I do not need to detect selection change or anything. Could someone tell me how to do that? What methods would help etc? In case the title wasn't read, this is regarding DefaultTableModel in JTables.
set colors of rows based on index,
Table Row Rendering might give you some ideas.
be able to set color of columns also based on something
You can provide a custom render for any column. Then you can add you logic to color the column based on something. Read the JTable API and follow the link to the Swing tutorial on How to Use Table and you will find a section on creating a custom renderer.
I am using JTable for displaying the information. After rendering the information if I drag the columns to reorder them, the information is displayed in the same fashion in the session. But when I try to capture the changes by checking the column names by iterating the column names, the sequence is same as the older one. Why is the latest view not available from the API?
As commented by Hovercraft Full Of Eels, the column indices in the view change independently of the column indices in the model. JTable's JavaDoc has this to say about it:
By default, columns may be rearranged in the JTable so that the view's columns appear in a different order to the columns in the model. This does not affect the implementation of the model at all: when the columns are reordered, the JTable maintains the new order of the columns internally and converts its column indices before querying the model.
JTable offers the methods convertColumnIndexToModel() and convertColumnIndexToView() that you can use to translate column numbers from one to the other. You can use these to figure out if (and how) the columns were rearranged.
To be notified of column changes as they happen, use a TableColumnModelListener:
myTable.getColumnModel().addColumnModelListener( new TableColumnModelListener() {
//etc.
} );
I am trying to display numbers in the steps of 5,10,15,20 in a Jtable.
In case of 5 the column names will be 0,5,10,15...
In case of 10 the column names will be 0,10,20,30...
In case of 15 the column names will be 0,15,30,45...
In case of 20 the column names will be 0,20,40,60...
Right now I am able to display 5 and what I need is the same structure but by hiding the vertical cell grid between 5 and 10,15 and 20 and so on.After all this I should remove the column names 5,15,25 and so on.Its not merging columns because my cells are implementing JProgressBar and I need it for painting it in different proportions.Like a cell representing 0-5 may be painted from 0-3 or 3-5 or 2-4.And each cell may be painted based on some value like this.
EDIT::Something similar to Multiple - Span cell as in this link text but my need is merging almost alternate cells by hiding the grid rather than using an Array.Thats why I mentioned it as hiding the vertical border rather than merging the cell.
I think the best way to hide what you don't want to see is deleting it.
But If what you want is to hide or make invisible, most of swing components have a method call
setVisible(boolean value)
Here an example how to hide a row(I hope it helps):
http://www.rgagnon.com/javadetails/java-0216.html
The desired behavior is akin to the mirrored text editing field provided in Excel when a given cell is selected, allowing more space to view the contents of the cell. I have a JTable with 5 columns and n rows. Column 2 holds expressions that can be arbitrarily long, thus I'd like to provide a separate JTextField to work with for editing the contents of the expression cell per row. The other fields are directly editable in the table. When the user clicks on a field in column 2, however, I want to send them to the text field. Any contents preexisting in the cell should be appear in the text field and additional edits in the text field should be mirrored in the table cell. Likewise, if someone double-clicks on the cell and edits it directly, I want those changes reflected in the text field. Thus, the user can choose to edit in either space and both are updated. Ideally, they are updated per keystroke, but update upon hitting return is acceptable.
So, far I've got the JTable, TableModel, TableModelListener, JTextField, ListSelectionListener, and AbstractAction, working together to provide most of the functionality described above. I'm missing the reflection of direct table cell edits to the text field and per-keystoke updates.
Are their ideas on how best to construct this behavior?
Well, if you want to get data from the table to the cell then you add the code to your TableModel's setValueAt() function, which should run when the user changes the content in an editable cell. I don't think that will update per-keystroke though.
If you want to move data from the textbox to the table cell use code like this
myJTextField.getDocument().addDocumentListener(new MyDocumentListener());
Where MyDocumentListener is an implementation of the javax.swing.event.DocumentListener interface
That will get you per-keystroke updates from the box to the table. But for the other way around it's a bit trickier.
There are two ways you might be able to go about doing it
1) Add a key listener to the table, and when the user starts typing check to see what table element is active, and intercept keystrokes as they type. That's kind of messy, though.
2) Another option might be to try to grab or replace the component that the table is using to actually let the user make the changes. I think that JTable actually allows you to change the editor component if you dig around.