Java Code Examples for javax.swing.plaf.basic.BasicComboPopup#getList()

/**
 * Adjusts the width of the scrollpane used by the popup.
 */
protected void popupWider(BasicComboPopup popup) {
  JList<?> list = popup.getList();

  //  Determine the maximimum width to use:
  //  a) determine the popup preferred width
  //  b) ensure width is not less than the scroll pane width
  int popupWidth = list.getPreferredSize().width
      + 5 // make sure horizontal scrollbar doesn't appear
      + getScrollBarWidth(popup, scrollPane);

  Dimension scrollPaneSize = scrollPane.getPreferredSize();
  popupWidth = Math.max(popupWidth, scrollPaneSize.width);

  //  Adjust the width
  scrollPaneSize.width = popupWidth;
  scrollPane.setPreferredSize(scrollPaneSize);
  scrollPane.setMaximumSize(scrollPaneSize);
}
 

private void popupWider(BasicComboPopup popup) {
    @SuppressWarnings("unchecked")
    JList<E> list = (JList<E>) popup.getList();

    //  Determine the maximimum width to use:
    //  a) determine the popup preferred width
    //  b) limit width to the maximum if specified
    //  c) ensure width is not less than the scroll pane width

    int popupWidth = list.getPreferredSize().width
            + 5  // make sure horizontal scrollbar doesn't appear
            + getScrollBarWidth(popup, scrollPane);

    if (maximumWidth != -1) {
        popupWidth = Math.min(popupWidth, maximumWidth);
    }

    Dimension scrollPaneSize = scrollPane.getPreferredSize();
    popupWidth = Math.max(popupWidth, scrollPaneSize.width);

    //  Adjust the width

    scrollPaneSize.width = popupWidth;
    scrollPane.setPreferredSize(scrollPaneSize);
    scrollPane.setMaximumSize(scrollPaneSize);
}
 

/**
 * Returns the scroll pane used by the popup so its bounds can be adjusted.
 */
protected JScrollPane getScrollPane(BasicComboPopup popup) {
  JList<?> list = popup.getList();
  Container c = SwingUtilities.getAncestorOfClass(JScrollPane.class, list);

  return (JScrollPane) c;
}
 

private JScrollPane getScrollPane(BasicComboPopup popup) {
    @SuppressWarnings("unchecked")
    JList<E> list = (JList<E>) popup.getList();
    Container c = SwingUtilities.getAncestorOfClass(JScrollPane.class, list);

    return (JScrollPane) c;
}
 

private boolean horizontalScrollBarWillBeVisible(BasicComboPopup popup, JScrollPane scrollPane) {
    @SuppressWarnings("unchecked")
    JList<E> list = (JList<E>) popup.getList();
    int scrollBarWidth = getScrollBarWidth(popup, scrollPane);
    int popupWidth = list.getPreferredSize().width + scrollBarWidth;

    return popupWidth > scrollPane.getPreferredSize().width;
}
 

private void makeComboBoxDropDownWider() {
	Object child = comboBox.getAccessibleContext().getAccessibleChild(0);
	BasicComboPopup popup = (BasicComboPopup) child;
	Insets borderInsets = popup.getBorder().getBorderInsets(popup);
	JList<?> list = popup.getList();
	Dimension preferred = list.getPreferredSize();

	IntUnaryOperator extractWidth = i -> comboBox.getRenderer()
			.getListCellRendererComponent(list, model.getElementAt(i), i, false, false)
			.getPreferredSize().width + 3;
	preferred.width = IntStream.range(0, model.getSize()).map(extractWidth)
			.reduce(comboBox.getWidth() - borderInsets.left - borderInsets.right, Integer::max);

	int itemCount = comboBox.getItemCount();
	int rowHeight = 10;
	if (itemCount > 0) {
		rowHeight = preferred.height / itemCount;
	}
	int maxHeight = comboBox.getMaximumRowCount() * rowHeight;
	preferred.height = Math.min(preferred.height, maxHeight);

	Container c = SwingUtilities.getAncestorOfClass(JScrollPane.class, list);
	JScrollPane scrollPane = (JScrollPane) c;

	scrollPane.setPreferredSize(preferred);
	scrollPane.setMaximumSize(preferred);

	if (popup.isShowing()) { // 
		// a little trick to fire Popup.showPopup method that takes care of correct display
		popup.setLocation(comboBox.getLocationOnScreen().x, popup.getLocationOnScreen().y - 1);
	}

	Dimension popupSize = new Dimension();
	popupSize.width = preferred.width + borderInsets.left + borderInsets.right;
	popupSize.height = preferred.height + borderInsets.top + borderInsets.bottom;
	Component parent = popup.getParent();
	if (parent != null) {
		parent.setSize(popupSize);
		parent.validate();
		parent.repaint();
	}
}
 

public static void setComboBoxSelectionColor(JComboBox comboBox, Color color) {
	Object child = comboBox.getAccessibleContext().getAccessibleChild(0);
	BasicComboPopup popup = (BasicComboPopup)child;
	JList list = popup.getList();
	list.setSelectionForeground(color);
}