Big problem with JSplitPane

Question

Hello,
I feel I'm going mad with Swing.
I have a main main JTabbedPane: main.
First component: JEditorPane : source
Second Component: JPanel : view( = new JPanel())
In view I have:
JPanel toolbox to NORTH and JSplitPane: ds to CENTER.
In ds I have:
Left component: new JScrollPane(design) where design=new JPanel()
Right component: JSplitPane(....) : called pe
First problem:
In ds the left component is too small. I tried to use all functions available , no result. I want the right component(pe) to have width=200, but no chance. It is too big. Why?
Second problem:
The scrolls are not appearing on the left at the ds(JSplitPane)
Third problem:
I add different components to design JPanel(the one which is placed into a JScrollPane which is related to the second problem) but nothing happens. They won't appear on design which is the same and without no scrolls.
Please help me solve this Swing mistery.
Thank you all.

Answer 1

The split pane, by default, will size its two halves based on their preferred sizes. If the combined preferred sizes are too small (for the size of the spilt pane) then the extra space is distributed based on JSplitPane's resize weight. The default is to add the extra to the right hand side, see JSplitPane.setResizeWeight for an explanation. If you really want the right hand side to be exactly 200 pixels then you can programmatically move the divider to a location that would leave the right hand side to be 200. Or you can set the preferred size of the component you place there to 200 and set a resize weight that will give the extra space to the left instead of the right.
I am not sure about why the scroll bars are not showing up. Does it need scroll bars?
May I suggest creating a simple demo app to show the problem? Often I solve my own problems doing this otherwise you have some code for us to look at and play with.
Ian