org.metawidget.swt.layout.MigLayout Maven / Gradle / Ivy
// Metawidget
//
// For historical reasons, this file is licensed under the LGPL
// (http://www.gnu.org/licenses/lgpl-2.1.html).
//
// Most other files in Metawidget are licensed under both the
// LGPL/EPL and a commercial license. See http://metawidget.org
// for details.
package org.metawidget.swt.layout;
import static org.metawidget.inspector.InspectionResultConstants.*;
import java.util.Map;
import net.miginfocom.layout.CC;
import net.miginfocom.layout.LC;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.metawidget.layout.iface.AdvancedLayout;
import org.metawidget.swt.Facet;
import org.metawidget.swt.Stub;
import org.metawidget.swt.SwtMetawidget;
import org.metawidget.util.WidgetBuilderUtils;
import org.metawidget.util.simple.SimpleLayoutUtils;
import org.metawidget.util.simple.StringUtils;
/**
* Layout to arrange widgets using net.miginfocom.swing.MigLayout.
*
* Widgets are arranged in a table, with one column for labels and another for the widget.
*
* @author Stefan Ackerman
*/
public class MigLayout
implements AdvancedLayout {
//
// Private members
//
private final int mNumberOfColumns;
private final boolean mDebugMode;
//
// Constructor
//
public MigLayout() {
this( new MigLayoutConfig() );
}
public MigLayout( MigLayoutConfig config ) {
mNumberOfColumns = config.getNumberOfColumns();
mDebugMode = config.isDebugMode();
}
//
// Public methods
//
public void onStartBuild( SwtMetawidget metawidget ) {
// Do nothing
}
public void startContainerLayout( Composite container, SwtMetawidget metawidget ) {
container.setData( MigLayout.class.getName(), null );
State state = getState( container );
// The entire layout should fill both horizontally and vertically,
// with no insets. This allows us to be properly nested, as well as
// embedded within existing UIs, without alignment problems
LC layoutConstraints = new LC().insets( "0" );
// Debug Info (draws the red and blue lines)
if ( mDebugMode ) {
layoutConstraints.debug( 500 );
}
// Create the Layout
//
// Note: we don't use column/row constraints, because we don't know
// what the controls will be in advance. Rather, we use 'cell' and 'push'
org.eclipse.swt.widgets.Layout layout = new net.miginfocom.swt.MigLayout( layoutConstraints );
container.setLayout( layout );
// Calculate default label inset
//
// We top align all our labels, not just those belonging to 'tall' controls,
// so that tall controls, regular controls and nested Metawidget controls all line up.
// However, we still want the Labels to be middle aligned for one-line controls (such as
// Text boxes), so we top inset them a bit
state.defaultLabelVerticalPadding = new GC( container ).getFontMetrics().getLeading();
}
public void layoutWidget( Control control, String elementName, Map attributes, Composite container, SwtMetawidget metawidget ) {
// Do not render empty stubs
if ( control instanceof Stub && ( (Stub) control ).getChildren().length == 0 ) {
// Must 'CC.setHideMode', because already added to Composite
CC controlConstraints = new CC();
controlConstraints.setHideMode( 3 );
control.setLayoutData( controlConstraints );
control.setVisible( false );
return;
}
// Special support for large controls
State state = getState( container );
boolean spanAllColumns = control instanceof SwtMetawidget || SimpleLayoutUtils.isSpanAllColumns( attributes );
if ( spanAllColumns && state.currentColumn > 0 ) {
state.currentColumn = 0;
state.currentRow++;
}
// Layout a label...
String labelText = null;
if ( attributes != null ) {
labelText = metawidget.getLabelString( attributes );
}
layoutBeforeChild( control, labelText, elementName, attributes, container, metawidget );
// ...and layout the control
CC controlConstraints = new CC();
if ( labelText != null ) {
controlConstraints.cell( ( state.currentColumn * 2 ) + 1, state.currentRow );
} else {
controlConstraints.cell( state.currentColumn * 2, state.currentRow );
controlConstraints.spanX( 2 );
}
controlConstraints.pushX( 1f ).growX();
if ( spanAllColumns ) {
controlConstraints.spanX();
state.currentColumn = mNumberOfColumns;
}
controlConstraints.alignY( "top" );
// Assume large controls should grow vertically
if ( willFillVertically( control, attributes ) ) {
controlConstraints.pushY( 1f ).growY();
}
// Add it
control.setLayoutData( controlConstraints );
state.currentColumn++;
if ( state.currentColumn >= mNumberOfColumns ) {
state.currentColumn = 0;
state.currentRow++;
}
}
public void endContainerLayout( Composite container, SwtMetawidget metawidget ) {
// Do nothing
}
public void onEndBuild( SwtMetawidget metawidget ) {
// Buttons
Facet buttonsFacet = metawidget.getFacet( "buttons" );
if ( buttonsFacet != null ) {
State state = getState( metawidget );
if ( state.currentColumn > 0 ) {
state.currentColumn = 0;
state.currentRow++;
}
buttonsFacet.setLayoutData( new CC().cell( 0, state.currentRow ).spanX().growX() );
buttonsFacet.moveBelow( null );
}
}
//
// Protected methods
//
protected String layoutBeforeChild( Control control, String labelText, String elementName, Map attributes, Control container, SwtMetawidget metawidget ) {
State state = getState( (Composite) container );
// Add label
if ( SimpleLayoutUtils.needsLabel( labelText, elementName ) ) {
Label label = new Label( (Composite) container, SWT.None );
// Required
if ( attributes != null && TRUE.equals( attributes.get( REQUIRED ) ) && !WidgetBuilderUtils.isReadOnly( attributes ) && !metawidget.isReadOnly() ) {
label.setText( labelText + "*" + StringUtils.SEPARATOR_COLON );
} else {
label.setText( labelText + StringUtils.SEPARATOR_COLON );
}
CC labelConstraints = new CC();
labelConstraints.cell( state.currentColumn * 2, state.currentRow );
labelConstraints.growX();
// Top align all labels, not just those belonging to 'tall' controls,
// so that tall controls, regular controls and nested Metawidget
// controls all line up
labelConstraints.alignY( "top" );
// Apply some vertical padding so the label lines up with the control nicely
labelConstraints.pad( state.defaultLabelVerticalPadding, 0, state.defaultLabelVerticalPadding, 0 );
// Add it
label.setLayoutData( labelConstraints );
label.moveAbove( control );
}
return labelText;
}
/**
* @param control
* control that may fill vertically
*/
protected boolean willFillVertically( Control control, Map attributes ) {
if ( attributes != null && TRUE.equals( attributes.get( LARGE ) ) ) {
return true;
}
return false;
}
//
// Private methods
//
private State getState( Composite container ) {
State state = (State) container.getData( MigLayout.class.getName() );
if ( state == null ) {
state = new State();
container.setData( MigLayout.class.getName(), state );
}
return state;
}
//
// Inner class
//
/**
* Simple, lightweight structure for saving state.
*/
/* package private */static class State {
/* package private */int currentColumn;
/* package private */int currentRow;
/* package private */int defaultLabelVerticalPadding;
}
}