如何更改JPanel的大小以适合动态生成的JBList？

Question

I'm trying to create a popup plugin for IntelliJ. The popup contains a JPanel (parentPanel), which contains a JList (I use JBList which is just a sublcass for Intellij) and JTextField. The contents of the list are built dynamically, depending on the contents of the JTextField when the user presses TAB.

This is what I am currently trying. The result is that a new JList is constructed with the proper elements, but the JPanel stays the exact same size, so most of the JList is obstructed. How can I expand the panel (and the whole popup) so that the entire list is visible?

Am I doing something wrong with JPanel, or is the size constrained by the popup itself?

parentPanel receives GridLayout from this line

this.setLayout(new GridLayout(2,1));

Here is the code which modifies the JList.

DefaultListModel listModel = (DefaultListModel) parentPanel.getFileList().getModel();
listModel.removeAllElements();
VirtualFile[] children = currentPathFile.getChildren();

for(int i = 0; i < children.length; ++i) {
   listModel.addElement(children[i].getPath());
}
parentPanel.remove(1); // The list is the panel's second child
parentPanel.add(new JBList(listModel));
parentPanel.revalidate();
parentPanel.repaint();

Even if I give the GridLayout 10 rows, the JList only occupies one row.

Answer 1

If parentPanel is a JPanel , its default layout is FlowLayout , which retains the initial preferred size, typically defined by the preferred size of the original content. Try changing it to GridLayout , which will allow the list to grow and shrink as the enclosing panel is resized.

That doesn't work either. GridLayout code has been added.

Because JBList extends JList , you may be able to use setVisibleRowCount() , as shown here .