/*
* Copyright 2011 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.guvnor.client.common;
import com.google.gwt.event.dom.client.BlurEvent;
import com.google.gwt.event.dom.client.BlurHandler;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.dom.client.KeyPressEvent;
import com.google.gwt.event.dom.client.KeyPressHandler;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.user.client.ui.TextBox;
/**
* A TextBox to handle restricted entry
*/
public abstract class AbstractRestrictedEntryTextBox extends TextBox {
protected final boolean allowEmptyValue;
public AbstractRestrictedEntryTextBox() {
this( false );
}
public AbstractRestrictedEntryTextBox(final boolean allowEmptyValue) {
this.allowEmptyValue = allowEmptyValue;
setup();
}
protected void setup() {
final TextBox me = this;
//Validate value as it is entered
this.addKeyPressHandler( new KeyPressHandler() {
public void onKeyPress(KeyPressEvent event) {
// Permit navigation
int keyCode = event.getNativeEvent().getKeyCode();
if ( event.isControlKeyDown()
|| keyCode == KeyCodes.KEY_BACKSPACE
|| keyCode == KeyCodes.KEY_DELETE
|| keyCode == KeyCodes.KEY_LEFT
|| keyCode == KeyCodes.KEY_RIGHT
|| keyCode == KeyCodes.KEY_TAB ) {
return;
}
// Get new value and validate
int charCode = event.getCharCode();
String oldValue = me.getValue();
String newValue = oldValue.substring( 0,
me.getCursorPos() );
newValue = newValue
+ ((char) charCode);
newValue = newValue
+ oldValue.substring( me.getCursorPos() + me.getSelectionLength() );
if ( !isValidValue( newValue,
false ) ) {
event.preventDefault();
}
}
} );
//Add validation when looses focus (for when values are pasted in by users')
this.addBlurHandler( new BlurHandler() {
@Override
public void onBlur(BlurEvent event) {
final String value = me.getText();
if ( !isValidValue( value,
true ) ) {
final String validValue = makeValidValue( value );
me.setText( validValue );
ValueChangeEvent.fire( AbstractRestrictedEntryTextBox.this,
validValue );
}
}
} );
}
/**
* Validate value of TextBox
*
* @param value
* @param isOnFocusLost
* Focus has been lost from the TextBox
* @return True if valid
*/
public abstract boolean isValidValue(String value,
boolean isOnFocusLost);
/**
* If validation fails (e.g. as a result of a user pasting a value) when the
* TextBox looses focus this method is called to transform the current value
* into one which is valid. This default implementation returns an empty
* String, however numerical TextBoxes could check the value is numerical
* and scale to that suitable for the type.
*
* @param value
* Current value
* @return A valid value
*/
protected String makeValidValue(String value) {
return "";
}
}