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javadraggablejscrollpaneboxlayout

Java draggable JPanel within JScrollPane with boxLayout

I have (1)JPanel containing (2)JPanel with BoxLayout. (2)JPanel can contain any number of (n)JPanels with FlowLayout (no of orders). (1)JPanel is put into JScrollPane using JScrollPaneLayout. I want (n)JPanels to be draggable to switch positions of (n)JPanels, but still maintain BoxLayout. For example I have JPanel with BoxLayout and 4 JPanels, I want to insert 4th JPanel between 1st and 2nd by dragging it in between, initial 2nd JPanel would automatically be moved to 3rd spot.

I already made (n)JPanels draggable, but I can't figure out a way to get position in which they should be inserted:

private void handleDrag(final JPanel panel){
    panel.addMouseListener(new MouseAdapter() {

        @Override
        public void mousePressed(MouseEvent me) {
             panelX = me.getX();
             panelY = me.getY();
        }

        @Override
        public void mouseReleased(MouseEvent me2){

            // get position of Component

            boxPanel.add(panel, position);

            scroll.revalidate();
        }
    });

    panel.addMouseMotionListener(new MouseMotionAdapter() {

        @Override
        public void mouseDragged(MouseEvent me) {
            me.translatePoint(me.getComponent().getLocation().x - panelX, me.getComponent().getLocation().y - panelY);
            panel.setLocation(0, me.getY());
        }
    });

I want to change positions of components in JPanel using BoxLayout by dragging JPanel to position, but I want JPanel to maintain BoxLayout.

Solution

  • Code I end up using, might be helpful to someone else.

    private void handleDrag(final JPanel panel){

    panel.addMouseListener(new MouseAdapter() {
        @Override
        public void mousePressed(MouseEvent me) {
             panelY = me.getY();

             panelNo = rowPanel.indexOf(panel);
             tempItem = rowPanel.get(panelNo);

             tempItem.setBackground(panelActiveColor);
             tempItem.setBorder(BorderFactory.createRaisedBevelBorder());
        }

        @Override
        public void mouseReleased(MouseEvent me){

            tempItem.setBackground(panelColor);
            tempItem.setBorder(BorderFactory.createEmptyBorder());
            scroll.revalidate();
        }
    });

    panel.addMouseMotionListener(new MouseMotionAdapter() {
        @Override
        public void mouseDragged(MouseEvent me) {
            me.translatePoint(0, me.getComponent().getLocation().y - panelY);

            int temp;

            if((int) ((me.getY() - panelY) / me.getComponent().getSize().height) < 0){
                temp = 0;
            }
            else if((int) ((me.getY() - panelY) /  me.getComponent().getSize().height) < (elementsAmount - 1)){
                temp = (me.getY() - panelY) /  me.getComponent().getSize().height + 1;
            }
            else{
                temp = (elementsAmount - 1);
            }

            rowPanel.remove(tempItem);

            rowPanel.add(temp, tempItem);

            boxPanel.add(tempItem, temp);

            scroll.revalidate();
        }
    });
}