constraintTextBox.setWidth( "300px" );
constraintTextBox.setText( constraint.getConstraint() );
constraintTextBox.addFocusHandler( new FocusHandler() {
public void onFocus(FocusEvent event) {
constraintTextBox.selectAll();
}
} );
constraintTextBox.addBlurHandler( new BlurHandler() {
public void onBlur(BlurEvent event) {
final Constraint constraint = constraints.get( connectionRef );