JScrollPane and JList auto scroll

Question

I\'ve got the next code:

    listModel = new DefaultListModel();
    listModel.addElement(dateFormat.format(new Date()) + \": Msg1\");
    messageList = new          


        

Answer 1

I used JScrollPane with JTextArea. I avoided force scroll down by scrolling only when JScrollBar max value changed:

JScrollPane scrollPane = new JScrollPane(jTextArea);

verticalScrollBarMaximumValue = scrollPane.getVerticalScrollBar().getMaximum();
scrollPane.getVerticalScrollBar().addAdjustmentListener(
    e -> {
        if ((verticalScrollBarMaximumValue - e.getAdjustable().getMaximum()) == 0)
            return;
        e.getAdjustable().setValue(e.getAdjustable().getMaximum());
        verticalScrollBarMaximumValue = scrollPane.getVerticalScrollBar().getMaximum();
    }
);

I suppose, there is better solution to filter events without extra variables, and would appreciate if somebody post it.