JComboBox sizing issue in a table with Multi line Cells - java

I recently had a problem where I needed to have a field that can wrap the text and increase the height of the row as the text is wrapped, similar to Microsoft Excel. I managed to get it working correctly, the only problem is that the table contains multiple JComboBoxes. When the row's height increases from the field that wraps the text, the size of the JComboBox window and ArrowButton also increase. I am using a DefaultCellEditor for the JComboBox fields, and created my own Editor/Renderer to be used with the JTextArea field. Once the JComboBox's value is selected, the value gets displayed correctly in the field, the only problem is while I am selecting the value, the JComboBox window and ArrowButton could be HUGE depending on the size of the row. Is there any way to increase the height of the row, but have the JComboBox field height remain the same instead of growing to fill the column that it's in? I am thinking I might need to make a Custom Cell Editor for the JComboBox fields as well instead of using the default. Thanks in advance!

I am thinking I might need to make a
Custom Cell Editor for the JComboBox
fields as well instead of using the
default
That would probably be the solution since the size of the editor is determined by the size of the cell.
I would try using a JPanel with a BorderLayout as the editor component. Then you add your editor to the North of the panel.
It would be the easiest editor to create since all the mouse events and key events are passed to the editor I believe, which means the panel will get the events, not the combo box. So I guess you would need to forward these events to the combo box.

First, is the JComboBox in a BorderLayout and set to BorderLayout.CENTER?
If so, I'd change it to a different layout such as AbsoluteLayout so it does not stretch to fill the cell.
Also, I will also refer you to this post Putting JComboBox into JTable

Related

How to scroll horizontally within a single column of a resizeable JTable?

I am making a dialog for the purpose of selecting multiple file paths. My dialog consists of two panels. One for buttons such as "Add" and "Remove", and a second panel containing a JTable wrapped in a scrollPane. The table has only one column. The cells of the table are not editable directly. When a user selects a file using a JFileChooser, the full path of that file will be added to the table. Although my dialog is resizeable, I still need a horizontal scroll behavior in the event that the file path is longer than the user's screen is wide.
I have researched the combination of resizeable table and horizontal scroll bar. That is similar, but not my issue. The typical scroll behavior is that the columns are scrolled, not the contents of the columns. I need the contents of a single column to scroll horizontally.
doesn't matter whether you scroll a multiple or only a single column: the basic issue is to get the horizontal scrollBar to start with :-)
There are two screws to tweak:
- enable horizontal scrolling by setting the table's resizeMode: default is to always fit the table's size to the size of the scrollPane, that is no scrolling
- resize the column width to fit its content
In a core JTable that maps into pseudo-code like
table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
// on receiving a TableModelEvent which might increase the column width
// calculate new width by measuring pref of the renderer
int newWidth = ...
// set it as pref of the column
table.getColumnModel().getColumn(0).setPreferredWidth(newWidth);
The catch is that without resizeMode, you are always responsible to sizing the column: it its width is less than the scrollPane, there's an empty region at its trailing side.
JXTable (part of SwingX project), supports an addition sizing mode which fills the available horizontal space as long as the table's prefWidts is less than parent width and shows a horizontal scrollBar if needed
table.setHorizontalScrollEnabled(true);
// on receiving a TableModelEvent which might increase the column width
// tell the table to re-evaluate
table.packColumn(0);
I selected kleopatra's answer as correct because it addresses my specific question regarding table manipulation. I am adding this answer because I ended up solving my root problem in a different manner.
I chose to use a JList to represent my file paths instead of a single column table. The only real reason that I had wanted to use the JTable was because of the appearance of the lined rows that a table has, and because of my unfamiliarity with JList. I discovered how to edit the appearance of the JList by extending the DefaultListCellRenderer. Because I now knew about editing the appearance, the JList's natural resizing and scroll behavior made it a much more natural fit to my needs.

Extending (sliding down) JTable row

I use jPanel as my cell and the table has just one column. It looks like this ( JTable: Buttons in Custom Panel in Cell ).
By default, the panel associated with the row (celll) contains a date when it was created. i want to implement an ActionListere method that will extend( slide down) the jpanel in which the action occured to see the whole jPanel data.
Hope you get what i mean.
Basically, you want to do the same thing that JList.ensureIndexIsVisible(int) but with a table.
Component has a method called "scrollRectToVisible(Rectangle aRect)" which should just about do what you need.
So, using your JTable, you can get the cellRect(int width, int height, boolean includingSpacing) and pass it off to the "scrollRectToVisible"
You're going to have to do some clever work to find out the row of the action, but I assume that you are using a table cell editor which has already provided you with this information

Trying to recreate Skype conversation panel with Swing

I am trying to recreate the Skype handles instant messaging using Swing components. I am using JList with a custom ListCellRenderer to render each cell in the list. The ListCellRenderer extends a JPanel, the JPanel simply contains a label (where I will put the username) and a JTextArea which is where the users' messages will go. The JTextArea is what Im having problems with.
Here's an image of what I have a the moment -
Ive removed the scrollpane that automatically comes with the textarea in netbeans.
I am showing the Navigator, the Design view and the actual program (the list has two elements) in this image.
The the text in textarea is actually much longer than in this image but it is not word wrapping. I have set lineWrap and wrapStyleWord to true in the properties box for this textarea but it doesn't seem to take any effect. I then tried to set maximum size using the properties box and that doesn't have any effect either.
Is there any way to control the padding/margins around components with netbeans gui designer. The automatic placement it gives me for spacing between components is either several pixels too small or two large. I need exact placement on the list's cell components.
For reference here is how skype's convesation panel looks (ive added in the red "Brian cs"'s as thats how I will be doing it in my program). As you can see the sentences wrap and there is an appropriate amount of space between cells. So anyone know how to achieve this using Swing?
The JTextarea is not the problem. The JList sets the heigth for each row. See JList.setFixedCellHeigth or setPrototypeCellValue

How to apply another LayoutManager to a JComboBox? (multi-column JComboBox attempt)

I'm trying to make a multi-column JComboBox. I've looked around quite a bit and it seems to be a very tricky thing to do. Unless many people, I'm not interested in having a table (where you select a row): I need to eliminate the scroll bar in the JComboBox and, in order to achieve this, I want to lay its items in a multi-column list instead of having them in only one column.
My best bet so far was to do this:
JComboBox dropdown = new JComboBox(validValues);
CellRendererPane crp = (CellRendererPane) dropdown.getComponent(1);
crp.setLayout(new GridLayout(4, 4)); // for 16 items...
But it doesn't work. It still lays cells in a single column. I tried adding items after setting the LayoutManager, but it doesn't affect the result.
Anyone has a clue about how to achieve this?
So far, I've seen the ListCellRenderer as useless to play with. It only specifies how to draw a cell (one at a time), not how to lay all of them (what is their relative position to each other).
Any help is welcome!
Thanks!
MJ
A combobox uses a JList to render the items in a popup. By default each item is displayed in a single row. You can access this list directly using:
Object child = comboBox.getAccessibleContext().getAccessibleChild(0);
BasicComboPopup popup = (BasicComboPopup)child;
JList list = popup.getList();
Now that you have acess to the list you should be able to change the default display by using:
list.setLayoutOrientation(JList.HORIZONTAL_WRAP);
Hopefully the items will now wrap when the width of the dropdown is reached. The width of the dropdown is controlled by the width of the combo box so you may need to play with the width of the combo box by using:
list.setPrototypeDisplayValue(....);
Edit:
Actually, forget about using setPrototypeDisplayValue(...), I think you will need to manually set the size of the popup.
By default the width of the popup is always equal to the width of the combo box. You can modify this behaviour by using a PopupMenuListener to override the size of the popup. To get you started you can look at the Combo Box Popup entry. Your code will be much simpler since all you will need to do is hardcode the desired width of your popup.

How to adjust components and JTable in a JFrame dynamically?

When i try to hide the rows in a jTable, the jTable ScrollPanel need to adjust its size to remaining rows and, other components in the Frame also adjust to the change. i.e., there shouldn't be any space between the components and the jTable after hiding the table-rows..
ex: in microsoft excel, when we delete a row, the remaining rows will move upwards to fill the deleted row..
Please help me.. Thank you..
Edited:
Used a model that extends AbstractTableModel. Used RowFilter to hide the rows.
Problem is even when the rows disapper, the JScrollpane(where the JTable resides) wont get adjusted to the remaining rows..
You can use setPreferredScrollableViewportSize() to resize the scroll pane to the desired multiple of getRowHeight(). You can use validate() "to cause a Container to lay out its subcomponents again" or pack() to cause the Window "to be sized to fit the preferred size and layouts of its subcomponents."
Are you trying to hide rows or delete rows? You mention hiding rows in JTable but deleting them in Excel.

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