When I make a JTable; I have the columns, and a single row, and then beneath that I have space for ~20 more rows, more if I increase the window size. I cannot have less as if I reduce the window size I just get a vertical scroll bar.
What I would like to do is make it so that the JTable size only goes to the last row.
I thought something like this:
newTable.setMaximumSize(new Dimension(Integer.MAX_VALUE, (newTable.getRowCount() + 1) * newTable.getRowHeight()));
But this does absolutely nothing. Using setPreferred size instead makes a white background about one row bigger, but the actual table is still the same size.
http://i.imgur.com/ClpD1Y3.png
I also tried the same things on the scrollpane that the JTable is in, setting the max / min sizes did nothing, setting the preferred size allowed me to make the table smaller by resizing the window, so I'm guessing that I may be able to do what I want using this and a layout perhaps? But I get class cast exceptions when trying to give a layout to the scrollpane. So I'm unsure what to do.
Set the preferredSize of the container that the JTable is in, ie. the scrollpane
Related
So, for example, I created a text field.
Tried to resize it
But once I release the mouse, it gets back to its original size
So how do I do it? How do I resize elements? And yes, I tried to change the minimum size, maximum size, preferred size but it does not work either, nothing happens.
You can do setLayout(null) on the parent or setPreferredSize on the components, either of which will allow you to resize your Components. But the best answer is to set your Font size to a larger size (setFont(...)) which will cause them to become bigger (have larger values in getPreferredSize) automatically.
JTextField tf = ...;
tf.setFont(tf.getFont().deriveFont(tf.getFont().getSize() * 2));
Since a picture is worth a thousand words:
I have JTable inside a JScrollPane, and currently the table has 10 columns. Each column is given a minimum width (given by setMinWidth(...)).
First picture: When the JFrame is stretched beyond the sum of all of the minimum widths of all columns then the columns are stretched to fill the window: this is the desired effect (do not want empty space at far right of frame).
Second picture: However when the JFrame is set to a size smaller than this combined minimum size, the horizontal bar does not show up properly and it becomes impossible to view the far right columns. Currently I have JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS as the horizontal bar option hince why for both pictures the horizontal bar container (appropriate name?) is there, but the actual bar itself never shows up. If I have JScrollPane.HORIZONTAL_SCROLLBAR_OFF, the horizontal bar container never shows.
Vertical works fine btw.
I have tried many things, including disabling auto resizing and trying to set the column widths myself when the JScrollPane width exceeds the min width sum of the columns. It doesn't seem right that I would have to do that manually myself. I can provide my code if necessary, but I don't think that it is necessary because it's just a JScrollPane hosting a JTable.
The solution was to overwrite the getScrollableTracksViewportWidth() method:
#Override
public boolean getScrollableTracksViewportWidth() {
return (getPreferredSize().width < getParent().getWidth());
}
I have a JScrollPane embedded in a GridBagLayout.
Most the time the content of the JScrollPane is smaller than the available space.
In this case I want the JScrollPane be exact the size it needs to be.
For example, if I have 10 Lines of text with a total height of 100px the JScrollPane should be 100px, without any scroll bars.
(This doesn't has to be dynamic it would be enought if I could set the maximum size, the content will not change.)
Only if I resize the JFrame and the available space becomes smaller than the content of the JScrollPane I want the JScrollPane to shrink and the scrollbars to appear.
I've tried to use the GridBagConstraints.fill parameter.
That works for the resizing to any size but it also always fills the whole space (what it is supposed to do if use the fill parameter , I think).
If I just set the size of the JScrollPane via setPreferedSize() wihtout the fill parameter and the Frame becomes smaller than this preferedSize the scrollPane immediately shrinks to a tiny chunk (as I read I shouldn't use the setPreferedSize method anyway(?)).
I've also tried the BoxLayout with the prefered and minimum size but if the available space becomes smaller than the prefered size the JScollPane instantly uses it's minimum size.
To sum up: I need a JScrollPane which resizes depending on the available space but only up to a maximum size.
What layout and settings do I have to use to get the desired result?
I am struggling with this problem since hours :(
EDIT:
Here a few screenshots:
The JScrollPane on the left side below Radio 1 and 2.
The frame in the normal size, the JScrollPane only uses the space it needs:
If I make it larger the JScrollPane shall not change (works):
But if I make the Frame smaller than the JScrollpane, the components get messed up:
What I want it to look like:
I mean when I resize the frame to the left or right side the table automatically resizes itself but I want the same future when I resize it from down or up sides of the table. There is scroll for down and up but I want default size to be smaller.
In fact aJScrollPane.setSize() doesn't work, aJPanel.setSize() too. Can you help me?
If you are trying to restrict the number of rows the table displays by default, you can use JTable.setPreferredScrollableViewportSize(). For example for 10 rows you can do the following:
table.setPreferredScrollableViewportSize(
new Dimension(table.getPreferredScrollableViewportSize().width,
10 * table.getRowHeight()));
Note however, table rows can have variable heights. Also note, that hard-coding sizes in general can have side effects.
I have a JScrollPane with a JTable in it. In the JTable I have initially 3 rows. Later on rows get added.
The default JTable with my 3 rows is ugly because JScrollPane calls getPreferredScrollableViewportSize from the client (JTable) and the return value is always the same. That's why my JTable/JScrollpane with 3 rows has this free space, JScrollpane andJTable do not have the same size.
My solution is to make a subclass JTable, override getPreferredScrollableViewportSize and return in this function getPreferredSize();. Now the whole JScrollPane has exactly the size of the 3 row `JTable!
When a row gets added I have the command ((JComponent) scrollPane.getParent()).revalidate();
The scrollpane grows with the table.
Everything works fine!
But now I want to set a certain layout for the container of the scrollpane (panel):
myjpanel.setLayout (new BoxLayout(contentPane, BoxLayout.Y_AXIS));
When I add this command my whole solution doesn't work anymore.
The scrollpane hasn't the size of the 3 row table, this free space is there again.
Why is this?
Does anybody have a solution?
CONTINUED
Thank you camickr for pointing me in the right direction. My solution is the following:
scrollPane = new JScrollPane (table) {
public Dimension getMaximumSize () {
double height = 0;
double width = super.getMaximumSize().getWidth();
height += columnHeader.getViewSize().getHeight();
height += viewport.getView().getPreferredSize().getHeight();
height += (getViewportBorderBounds().getHeight() * -1);
Dimension returnValue = new Dimension ((int) width, (int) height);
return returnValue;
}
};
It works now at the beginning.
But when a row is added to the jtable and I call revalidate(); on the jpanel (parent container of the scrollpanel) the jscrollpanel shrinks in height to 1 row + header!
Has anyone got an idea what is to do in this situation.
CONTINUED
Now I know the problem. It is the viewportBorder. In order to get the whole, exact height I have to total the height of the view (Jtable), the height of the column header and the height of the viewportBorder. The first time getViewportBorderBounds().getHeight() returns -3, next time - after a new row is inserted in the table model - the function returns 48. I do not understand why this function returns 48 now.
Another point is that camickr says that changing the size of the jscrollpane defeats the purpose of the scrollpane. I do not understand this. How can anyone be satisfied with a default jscrollpane size of 450 x 400 (http://www.javalobby.org/java/forums/t19559.html) even when the jtable has only 3 lines at the beginning. This unfilled extra space does not look very professional in my eyes. Has anyone got a better solution for this.
Thank you very much for your answers
CONTINUED
Now everything works!
At the beginning I simply set the jscrollpane border to 0 ... sp.setBorder(createEmptyBorder());
In this way I avoid having these strange return values of getViewportBorderBounds().getHeight()
Wolfgang
The BoxLayout allows the component to grow up to the maximum size of the component. I guess you need to override the getMaximumSize() of the scrollpane to return the preferred size.
When a row gets added I have the command "((JComponent) scrollPane.getParent()).revalidate();" The scrollpane grows with the jtable.
That kind of defeats the purpose of the scrollpane. The scrollbar is supposed to stay at a fixed size and then scrollbars will appear if necessary.
I had a similar problem - the basic upshot is that I wanted a JTable in a scroll pane that had a minimum and maximum size: when there was no data in the table, it should have a one-row-height pane background displayed (not a fake row, obviously), and when it was over 10 rows to limit the displayed table size to those 10 rows plus scrollbars. Any size between 1 and 10 should display the table at full height. The situation was a parent-child table, and this was the child table, so I had to trigger the child table resize depending on which parent table row was clicked. A fixed pane size looked ugly in that it took up unnecessary space to push other potentially viewable info under the child table out of view with just blank space.
Using the setPreferredScrollableViewportSize after updating the model with the child rows (and setFillsViewportHeight(true) of course) gave me almost everything I needed. Except that the viewport wouldn't redraw until I clicked on it, or took focus from the window then flicked back, it was most annoying.
The solution was super-simple after reading this post: I just had to call revalidate on the scrollpane's parent, as pointed out in the solution. Fixed it perfectly. Mostly I just wanted to share a use case where you want the scrollpane size to change dynamically up to a maximum size. Swing is so much simpler if everything is created at a fixed size forever... unlike pretty much every real-life use case I've ever encountered :-)