org.metawidget.gwt.client.ui.layout.FlexTableLayout Maven / Gradle / Ivy
// Metawidget (licensed under LGPL)
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package org.metawidget.gwt.client.ui.layout;
import static org.metawidget.inspector.InspectionResultConstants.*;
import java.util.HashMap;
import java.util.Map;
import org.metawidget.gwt.client.ui.Facet;
import org.metawidget.gwt.client.ui.GwtMetawidget;
import org.metawidget.gwt.client.ui.Stub;
import org.metawidget.layout.iface.AdvancedLayout;
import org.metawidget.util.simple.SimpleLayoutUtils;
import com.google.gwt.user.client.ui.ComplexPanel;
import com.google.gwt.user.client.ui.FlexTable;
import com.google.gwt.user.client.ui.FlexTable.FlexCellFormatter;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.Panel;
import com.google.gwt.user.client.ui.Widget;
/**
* Layout to arrange widgets in a FlexTable, with one column for labels and another for
* the widget.
*
* @author Richard Kennard
*/
public class FlexTableLayout
implements AdvancedLayout {
//
// Private statics
//
private static final int LABEL_AND_COMPONENT_AND_REQUIRED = 3;
//
// Private members
//
private final int mNumberOfColumns;
private final String mTableStyleName;
private final String[] mColumnStyleNames;
private final String mFooterStyleName;
//
// Constructor
//
public FlexTableLayout() {
this( new FlexTableLayoutConfig() );
}
public FlexTableLayout( FlexTableLayoutConfig config ) {
mNumberOfColumns = config.getNumberOfColumns();
mTableStyleName = config.getTableStyleName();
mColumnStyleNames = config.getColumnStyleNames();
mFooterStyleName = config.getFooterStyleName();
}
//
// Public methods
//
public void onStartBuild( GwtMetawidget metawidget ) {
// Do nothing
}
public void startContainerLayout( Panel container, GwtMetawidget metawidget ) {
State state = getState( container, metawidget );
FlexTable flexTable = new FlexTable();
flexTable.setStyleName( mTableStyleName );
container.add( flexTable );
state.formatter = flexTable.getFlexCellFormatter();
}
public void layoutWidget( Widget widget, String elementName, Map attributes, Panel container, GwtMetawidget metawidget ) {
// Do not render empty stubs
if ( widget instanceof Stub && ( (Stub) widget ).getWidgetCount() == 0 ) {
return;
}
// Calculate row and actualColumn. Note FlexTable doesn't work quite as might be
// expected. Specifically, it doesn't understand 'colspan' in relation to previous rows. So
// if you do...
//
// layout.setWidget( row, 0, widget1 );
// layout.setColSpan( row, 0, 2 );
// layout.setWidget( row, 2, widget2 );
//
// ...you'll actually get...
//
// widget1
// widget2
//
// ...note FlexTable inserts an extra attributes, Widget container, GwtMetawidget metawidget ) {
State state = getState( container, metawidget );
FlexTable flexTable = (FlexTable) ( (ComplexPanel) container ).getWidget( 0 );
int row = flexTable.getRowCount() - 1;
int column = flexTable.getCellCount( row );
state.formatter.setStyleName( row, column, getStyleName( ( state.currentColumn * LABEL_AND_COMPONENT_AND_REQUIRED ) + 2, metawidget ) );
if ( attributes != null && TRUE.equals( attributes.get( REQUIRED ) ) && !TRUE.equals( attributes.get( READ_ONLY ) ) && !metawidget.isReadOnly() ) {
flexTable.setText( row, column, "*" );
return;
}
// Render an empty div, so that the CSS can force it to a certain
// width if desired for the layout (browsers seem to not respect
// widths set on empty table columns)
//
// Note: don't do , as we may not be XHTML
flexTable.setHTML( row, column, "" );
}
/**
* @param metawidget
* the Metawidget doing the layout
*/
protected String getStyleName( int styleName, GwtMetawidget metawidget ) {
if ( mColumnStyleNames == null || mColumnStyleNames.length <= styleName ) {
return null;
}
return mColumnStyleNames[styleName];
}
protected boolean willFillHorizontally( Widget widget, Map attributes ) {
if ( widget instanceof GwtMetawidget ) {
return true;
}
return SimpleLayoutUtils.isSpanAllColumns( attributes );
}
//
// Private methods
//
/**
* Get the number of columns to use in the layout.
*
* Nested Metawidgets are always just single column.
*/
private int getEffectiveNumberOfColumns( Widget container ) {
if ( container.getParent() instanceof FlexTable && container.getParent().getParent() instanceof GwtMetawidget ) {
return 1;
}
return mNumberOfColumns;
}
private State getState( Widget container, GwtMetawidget metawidget ) {
@SuppressWarnings( "unchecked" )
Map stateMap = (Map) metawidget.getClientProperty( getClass() );
if ( stateMap == null ) {
stateMap = new HashMap();
metawidget.putClientProperty( getClass(), stateMap );
}
State state = stateMap.get( container );
if ( state == null ) {
state = new State();
stateMap.put( container, state );
}
return state;
}
//
// Inner class
//
/**
* Simple, lightweight structure for saving state.
*/
/* package private */static class State {
/* package private */FlexCellFormatter formatter;
/* package private */int currentColumn;
}
}