java grid bag layout: avoiding center alignment

alignment, gridbaglayout, java, jpanel, jscrollpane

Solution

I found a solution to my own question after some fiddling around:

Setting weights appears to be able to affect alignment of the components within the `JPanel` for which the `GridBagLayout` was used. However, it didn't have an effect on the alignment of the `JPanel` within the `JScrollPane`.

I found a rather simple solution, which is to not put the `JPanel` directly inside of the `JScrollPane`, as I was doing with my earlier code:

if (currentPanel != mCurrentPanel)
{
    mViewport.setViewportView(currentPanel);
}

... but instead to put an "outer" `JPanel` inside the `JScrollPane`, and set that to use a `FlowLayout`. Then when I want to switch panels, I remove the old and place the panel within the "outer" panel.

if (currentPanel != mCurrentPanel)
{
    if (mCurrentPanel != null)
    {
        mOuterPanel.remove(mCurrentPanel);
    }
    mCurrentPanel = currentPanel;
    mOuterPanel.add(mCurrentPanel);
}

This approach worked rather well, because it meant I only had to effect changes in one class, instead of each of the many panels I had.

Problem

In my GUI application, I have several JPanels that are instantiated at various points during the running of my program, and certain actions will cause one of them to be displayed in a scroll pane: ``` mViewport.setViewportView(currentPanel); ``` The trouble is, that my panels are done using Grid Bag Layouts, and the behaviour of that is to center itself within the JScrollPane it is inside of. This make the GUI look weird. Anyone know of a way to force a grid bag layout panel to top-left align? Thanks! EDIT Note that here I am asking about the alignment of the entire panel within its scroll pane, not about the components within the panel.

Original source