de.swm.commons.mobile.client.widgets.Slider Maven / Gradle / Ivy
/*
* Copyright 2011 SWM Services GmbH.
*
* 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 de.swm.commons.mobile.client.widgets;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.Style.Unit;
import com.google.gwt.editor.client.IsEditor;
import com.google.gwt.editor.client.LeafValueEditor;
import com.google.gwt.editor.client.adapters.TakesValueEditor;
import com.google.gwt.event.dom.client.*;
import com.google.gwt.event.logical.shared.HasValueChangeHandlers;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.HasValue;
import de.swm.commons.mobile.client.SWMMobile;
import de.swm.commons.mobile.client.event.DragController;
import de.swm.commons.mobile.client.event.DragEvent;
import de.swm.commons.mobile.client.event.DragEventsHandler;
/**
* Integer value slider with data binding support.
*
*/
public class Slider extends SWMMobileWidgetBase implements DragEventsHandler, HasValueChangeHandlers,
IsEditor>, HasValue, HasFocusHandlers, HasBlurHandlers {
private static final int SCALE_FACTOR = 100;
protected int myValue = 0;
protected final FlowPanel contentPanel = new FlowPanel();
protected final HTML myLabel = new HTML(myValue + "");
protected final HTML mySlider = new HTML();
private LeafValueEditor editor;
/**
* Default constructor.
*/
public Slider() {
contentPanel.add(myLabel);
mySlider.setHTML("");
contentPanel.add(mySlider);
initWidget(contentPanel);
setStyleName(SWMMobile.getTheme().getMGWTCssBundle().getSliderCss().slider());
}
@Override
public void onLoad() {
super.onLoad();
DragController.get().addDragEventsHandler(this);
}
@Override
public void onUnload() {
DragController.get().removeDragEventsHandler(this);
}
@Override
public void onDragStart(DragEvent e) {
DragController.get().captureDragEvents(this);
int value = computeNewValue(e);
setValue(value);
}
@Override
public void onDragMove(DragEvent e) {
e.stopPropagation();
int value = computeNewValue(e);
setValue(value);
}
@Override
public void onDragEnd(DragEvent e) {
DragController.get().releaseDragCapture(this);
}
@Override
public Integer getValue() {
return myValue;
}
@Override
public HandlerRegistration addValueChangeHandler(ValueChangeHandler handler) {
return this.addHandler(handler, ValueChangeEvent.getType());
}
/**
* If the current value should be displayed.
*
* @param display
* true if the value should be displayed
*/
public void setDisplayValue(boolean display) {
if (display) {
myLabel.removeStyleName(SWMMobile.getTheme().getMGWTCssBundle().getSliderCss().hide());
} else {
myLabel.addStyleName(SWMMobile.getTheme().getMGWTCssBundle().getSliderCss().hide());
}
}
/**
* Computes the value after a Drag event (after the slider was moved)
*
* @param event
* the event
* @return the new value
*/
private int computeNewValue(DragEvent event) {
Element ele = getElement();
int offset = (int) event.getX() - ele.getAbsoluteLeft();
int width = ele.getClientWidth();
int value = offset * SCALE_FACTOR / width;
if (value > SCALE_FACTOR) {
value = SCALE_FACTOR;
} else if (value < 0) {
value = 0;
}
return value;
}
/**
* Enforce the slider position update.
*/
private void updateSliderPosition() {
myLabel.setHTML(myValue + "");
Element slider = getSliderElement();
slider.getStyle().setWidth(myValue, Unit.PCT);
}
private Element getSliderElement() {
return (Element) mySlider.getElement().getChild(1);
}
@Override
public LeafValueEditor asEditor() {
if (editor == null) {
editor = TakesValueEditor.of(this);
}
return editor;
}
/**
* Sets the value.
*
* @param value
* the value
*/
public void setValue(Integer value) {
if (value != null && myValue != value) {
myValue = value;
updateSliderPosition();
ValueChangeEvent.fire(this, myValue);
}
}
@Override
public void setValue(Integer value, boolean fireEvents) {
setValue(value);
}
@Override
public HandlerRegistration addBlurHandler(BlurHandler handler) {
return mySlider.addDomHandler(handler, BlurEvent.getType());
}
@Override
public HandlerRegistration addFocusHandler(FocusHandler handler) {
return mySlider.addDomHandler(handler, FocusEvent.getType());
}
}