singleselectionlist.java

FuncPlotter is a combined Java application and applet for displaying two-dimensional plots of explic

    public void setExtraWidth( int extraWidth )
    {
        if ( this.extraWidth != extraWidth )
        {
            this.extraWidth = extraWidth;
            resize( );
            repaint( );
        }
    }

    //------------------------------------------------------------------

    public void setSelectedIndex( int index )
    {
        if ( index != selectedIndex )
            forceSelectedIndex( index );
    }

    //------------------------------------------------------------------

    public void setViewport( JViewport viewport )
    {
        this.viewport = viewport;
    }

    //------------------------------------------------------------------

    public void setModel( Model<E> model )
    {
        this.model = model;
        resizeAndRedraw( );
    }

    //------------------------------------------------------------------

    public void setElement( int index,
                            E   element )
    {
        model.setElement( index, element );
        redrawElements( index, 1 );
    }

    //------------------------------------------------------------------

    public void setElements( E[] elements )
    {
        if ( model instanceof DefaultModel )
            ((DefaultModel<E>)model).setElements( elements );
        else
        {
            while ( getNumElements( ) > 0 )
                model.removeElement( getNumElements( ) - 1 );
            if ( elements != null )
            {
                for ( E element : elements )
                    model.addElement( getNumElements( ), element );
            }
        }
        resizeAndRedraw( );
    }

    //------------------------------------------------------------------

    public void setElements( List<E> elements )
    {
        if ( model instanceof DefaultModel )
            ((DefaultModel<E>)model).setElements( elements );
        else
        {
            while ( getNumElements( ) > 0 )
                model.removeElement( getNumElements( ) - 1 );
            if ( elements != null )
            {
                for ( E element : elements )
                    model.addElement( getNumElements( ), element );
            }
        }
        resizeAndRedraw( );
    }

    //------------------------------------------------------------------

    public void addElement( E element )
    {
        addElement( getNumElements( ), element );
    }

    //------------------------------------------------------------------

    public void addElement( int index,
                            E   element )
    {
        model.addElement( index, element );
        resize( );
        forceSelectedIndex( index );
    }

    //------------------------------------------------------------------

    public void removeElement( int index )
    {
        int length = getNumElements( ) - index;
        model.removeElement( index );
        resize( );
        redrawElements( index, length );
        if ( selectedIndex >= getNumElements( ) )
            forceSelectedIndex( getNumElements( ) - 1 );
    }

    //------------------------------------------------------------------

    public void moveElement( int fromIndex,
                             int toIndex )
    {
        if ( toIndex > fromIndex )
            --toIndex;
        if ( toIndex != fromIndex)
        {
            model.addElement( toIndex, model.removeElement( fromIndex ) );
            redrawElements( Math.min( fromIndex, toIndex ), Math.abs( fromIndex - toIndex ) + 1 );
        }
        forceSelectedIndex( toIndex );
    }

    //------------------------------------------------------------------

    public void snapViewPosition( )
    {
        if ( viewport != null )
        {
            Point viewPosition = viewport.getViewPosition( );
            int y = Math.max( 0, viewPosition.y ) / rowHeight * rowHeight;
            if ( viewPosition.y != y )
            {
                viewPosition.y = y;
                viewport.setViewPosition( viewPosition );
            }
        }
    }

    //------------------------------------------------------------------

    public void addActionListener( ActionListener listener )
    {
        actionListeners.add( listener );
    }

    //------------------------------------------------------------------

    public void removeActionListener( ActionListener listener )
    {
        actionListeners.remove( listener );
    }

    //------------------------------------------------------------------

    public void addListSelectionListener( ListSelectionListener listener )
    {
        selectionListeners.add( listener );
    }

    //------------------------------------------------------------------

    public void removeListSelectionListener( ListSelectionListener listener )
    {
        selectionListeners.remove( listener );
    }

    //------------------------------------------------------------------

    protected void fireActionPerformed( String command )
    {
        ActionEvent event = new ActionEvent( this, ActionEvent.ACTION_PERFORMED, command );
        for ( int i = actionListeners.size( ) - 1; i >= 0; --i )
            actionListeners.get( i ).actionPerformed( event );
    }

    //------------------------------------------------------------------

    protected void fireValueChanged( )
    {
        ListSelectionEvent event = new ListSelectionEvent( this, selectedIndex, selectedIndex, false );
        for ( int i = selectionListeners.size( ) - 1; i >= 0; --i )
            selectionListeners.get( i ).valueChanged( event );
    }

    //------------------------------------------------------------------

    protected void drawElement( Graphics gr,
                                int      index )
    {
        String str = getElement( index ).toString( );
        FontMetrics fontMetrics = gr.getFontMetrics( );
        int x = getComponentOrientation( ).isLeftToRight( )
                                        ? horizontalMargin
                                        : getWidth( ) - horizontalMargin - fontMetrics.stringWidth( str );
        int y = index * rowHeight + (rowHeight - fontMetrics.getHeight( )) / 2 + fontMetrics.getAscent( );
        gr.setColor( getForeground( ) );
        gr.drawString( str, x, y );
    }

    //------------------------------------------------------------------

    protected void resize( )
    {
        if ( viewport != null )
            viewport.setViewSize( getPreferredSize( ) );
        revalidate( );
    }

    //------------------------------------------------------------------

    protected void resizeAndRedraw( )
    {
        resize( );
        selectedIndex = -1;
        repaint( );
        forceSelectedIndex( (getNumElements( ) > 0) ? 0 : -1 );
    }

    //------------------------------------------------------------------

    protected void forceSelectedIndex( int index )
    {

        // Remove current selection

        if ( selectedIndex >= 0 )
        {
            int oldSelectedIndex = selectedIndex;
            selectedIndex = -1;
            redrawElements( oldSelectedIndex, 1 );
        }

        // Set selected index

        if ( (index >= -1) && (index < getNumElements( )) )
        {
            selectedIndex = index;
            makeSelectionViewable( );
            if ( selectedIndex >= 0 )
                redrawElements( selectedIndex, 1 );
            fireValueChanged( );
        }

    }

    //------------------------------------------------------------------

    private void redrawElements( int index,
                                 int length )
    {
        repaint( 0, index * rowHeight, getWidth( ), length * rowHeight );
    }

    //------------------------------------------------------------------

    private void setDragIndex( int index )
    {

        // Erase old drag bar

        if ( dragY != null )
        {
            dragIndex = -1;
            repaint( 0, dragY.intValue( ), getWidth( ), DRAG_BAR_HEIGHT );
            dragY = null;
        }

        // Draw new drag bar

        if ( index >= 0 )
        {
            dragIndex = index;
            int y = index * rowHeight - DRAG_BAR_HEIGHT / 2;
            repaint( 0, y, getWidth( ), DRAG_BAR_HEIGHT );
            dragY = new Integer( y );
        }

    }

    //------------------------------------------------------------------

    private void incrementSelectedIndex( int increment )
    {
        int index = (selectedIndex < 0) ? 0 : selectedIndex;
        setSelectedIndex( Math.min( Math.max( 0, index + increment ), getNumElements( ) - 1 ) );
    }

    //------------------------------------------------------------------

    private void makeSelectionViewable( )
    {
        if ( (viewport != null) && (selectedIndex >= 0) )
        {
            Point viewPosition = viewport.getViewPosition( );
            int y = viewPosition.y;
            int startIndex = y / rowHeight;
            if ( selectedIndex < startIndex )
                y = selectedIndex * rowHeight;
            else
            {
                if ( selectedIndex >= startIndex + viewableRows )
                    y = Math.max( 0, selectedIndex - viewableRows + 1 ) * rowHeight;
            }
            if ( viewPosition.y != y )
            {
                viewPosition.y = y;
                viewport.setViewPosition( viewPosition );
            }
        }
    }

    //------------------------------------------------------------------

    private void incrementViewY( int deltaY )
    {
        if ( deltaY != 0 )
            viewport.setViewPosition( new Point( viewport.getViewPosition( ).x,
                                                 viewport.getViewPosition( ).y + deltaY ) );
    }

    //------------------------------------------------------------------

    private void doSelectUpUnit( )
    {
        incrementSelectedIndex( -UNIT_INCREMENT_ROWS );
    }

    //------------------------------------------------------------------

    private void doSelectDownUnit( )
    {
        incrementSelectedIndex( UNIT_INCREMENT_ROWS );
    }

    //------------------------------------------------------------------

    private void doSelectUpBlock( )
    {
        incrementSelectedIndex( -BLOCK_INCREMENT_ROWS );
    }

    //------------------------------------------------------------------

    private void doSelectDownBlock( )
    {
        incrementSelectedIndex( BLOCK_INCREMENT_ROWS );
    }

    //------------------------------------------------------------------

    private void doSelectUpMax( )
    {
        setSelectedIndex( 0 );
    }

    //------------------------------------------------------------------

    private void doSelectDownMax( )
    {
        setSelectedIndex( getNumElements( ) - 1 );
    }

    //------------------------------------------------------------------

    private void doScrollUpUnit( )
    {
        if ( viewport != null )
            incrementViewY( -getScrollableUnitIncrement( viewport.getViewRect( ), SwingConstants.VERTICAL,
                                                         -1 ) );
    }

    //------------------------------------------------------------------

    private void doScrollDownUnit( )
    {
        if ( viewport != null )
            incrementViewY( getScrollableUnitIncrement( viewport.getViewRect( ), SwingConstants.VERTICAL,
                                                        1 ) );
    }

    //------------------------------------------------------------------

    private void doEditElement( )
    {
        if ( selectedIndex >= 0 )
            fireActionPerformed( Command.EDIT_ELEMENT );
    }

    //------------------------------------------------------------------

    private void doDeleteElement( )
    {
        if ( selectedIndex >= 0 )
            fireActionPerformed( Command.DELETE_ELEMENT );
    }

    //------------------------------------------------------------------

    private void doDeleteExElement( )
    {
        if ( selectedIndex >= 0 )
            fireActionPerformed( Command.DELETE_EX_ELEMENT );
    }

    //------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////
//  Instance variables
////////////////////////////////////////////////////////////////////////

    private int                         columns;
    private int                         viewableRows;
    private int                         columnWidth;
    private int                         rowHeight;
    private int                         horizontalMargin;
    private int                         extraWidth;
    private int                         selectedIndex;
    private int                         dragIndex;
    private int                         dragStartIndex;
    private int                         dragEndIndex;
    private Integer                     dragY;
    private JViewport                   viewport;
    private Model<E>                    model;
    private List<ActionListener>        actionListeners;
    private List<ListSelectionListener> selectionListeners;

}

//----------------------------------------------------------------------