I am having a strange problem, where using a jComboBox is causing screen repaint issues on the portion of the panel below the panel.
Specifically:
I have a panel with a table that is located below a combo box.
(The table has a colored header row)
Opening and closing the combo box (without selecting anything) causes the table header to get colored differently (changes to white).
The region that gets mis-colored is the table cell exactly below the combo box's handle. (starts at the left side of the cell and stops exactly where the combobox handle stops.)
Resizing the window makes the panel become colored properly. (which indicates to me that this is a paint problem, as described in: http://www.oracle.com/technetwork/java/javase/swing-135905.html)
Interestingly, it seems to happen only on Solaris (not Linux, have not tried windows).
Apologies in advance for not providing a working example, just looking for ideas at the moment for things to check.
Related
I have written a Swing UI that has a JPanel with numerous controls and on the right hand side a few columns of JCheckBoxes. This is all handled by making the JPanel use a GridLayout. The problem I am having is that a given checkbox toggles it's selection status no matter where in it's grid "cell" you click in. Note, I am not using a JTable approach. The "cell" is just the rectangular area of the screen the GridLayout gave to the checkbox. It can be much bigger than the checkbox. I can't figure out how to make sure the checkboxes are only selectable when you click in the tiny box of the drawn control (not the big box of the "cell" that the checkbox is basically centered in). I've googled a lot and everyone talks about JTables. Again, I am not using a JTable. This issue is causing headaches for my users as they click on the application window and accidentally select an option!
The GridLayout forces all UI components to fill their cell completely, so the actual checkbox only gives the illusion that it's smaller than the cell it occupies. The solution here, as with many other more complex UI designs, is to use multiple layouts nested inside one another.
In your case, try putting all your check boxes inside a BoxLayout and using glue to space them as needed. This BoxLayout should be placed side by side with your GridLayout in another enclosing container (either a JPanel or your ContentPane -- I can't say for sure because you only gave a brief description of your UI with no code or illustration).
Play around with the idea of nesting layouts until you get something you like, and don't forget to try resizing your window to see what the layout manager does under the circumstances. The final appearance isn't always exactly what you imagine it will be.
How can I tell when a column is resized by the user in an SWT TreeViewer? I initially thought it would be via ControlAdapter, but this also fires on initialization and if the application window gets resized.
Is it more appropriate to add a drag or mouseup listener? It doesn't seem (to me) that the TreeColumn initially supports this kind of behavior.
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
I've created an app with a small window (the size of a combo box). I need to create a floating panel that sits outside the window, next to the selected item in a JComboBox. (See attached image).
I've been reading about the JComboBox.setRenderer(customRenderer) etc. But was just wondering before I go down this path, whether it is at all possible to render something outside the window. I suspect it is, as the combobox itself manages to render it's popup list outside the window.
I'm very new to Swing, so any advice would be appreciated.
It's not possible with the custom renderer since Swing components are light weight. That is, Java is given a native window and all the component drawing takes place in that window. In your case, that is the JFrame containing the combo box.
What you can do though is create a new undecorated window and set it's location accordingly and draw whatever you want inside it.
EDIT: When Java needs to paint outside it's window bounds (like the case of pop up messages or combo boxes drop downs) if the component falls inside the bounds it uses the swing light weight mechanism. But if the component falls out side the bounds it is automatically substituted with a awt heavy weight component that has it's own native drawing surface outside the active window.
I've implemented similar idea using combobox renderers and tooltips on them. Content of every item's tooltip can be customized and rendered using HTML. Location of the tooltip can be set outside of the item itself thus creating design very similar to the one presented in your question.
Here is the starting point for you:
http://www.java2s.com/Code/Java/Swing-Components/ToolTipComboBoxExample.htm
I have a Java swing application with a panel that contains three JComboBoxes that do not draw properly.
The combox boxes just show up as the down arrow on the right side, but without the label of the currently selected value.
The boxes will redraw correctly if the window is resized either bigger or smaller by even one pixel.
All of my googling has pointed to calling revalidate() on the JPanel to fix this, but that hasn't worked for me.
Calling updateUI() on the JPanel has changed it from always displaying incorrectly to displaying incorrectly half of the time.
Has anyone else seen this and found a different way to force a redraw of the combo boxes?
Can you give us some more information on how you add the combo boxes to the JPanel? This is a pretty common thing to do in Swing so I doubt that it's a JVM issue but I guess anything is possible.
Specifically, I would double check to make sure you're not accessing the GUI from any background threads. In this case, maybe you're reading the choices from a DB or something and updating the JComboBox from a background thread, which is a big no-no in Swing. See SwingUtils.invokeLater().