/*
* Copyright 2010 IT Mill Ltd.
*
* 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 com.vaadin.terminal.gwt.client.ui;
import com.google.gwt.core.client.GWT;
import com.google.gwt.dom.client.DivElement;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.FormElement;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.DeferredCommand;
import com.google.gwt.user.client.Element;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.Timer;
import com.google.gwt.user.client.ui.FileUpload;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.FormPanel;
import com.google.gwt.user.client.ui.Hidden;
import com.google.gwt.user.client.ui.Panel;
import com.google.gwt.user.client.ui.SimplePanel;
import com.vaadin.terminal.gwt.client.ApplicationConnection;
import com.vaadin.terminal.gwt.client.Paintable;
import com.vaadin.terminal.gwt.client.UIDL;
import com.vaadin.terminal.gwt.client.VConsole;
/**
*
* Note, we are not using GWT FormPanel as we want to listen submitcomplete
* events even though the upload component is already detached.
*
*/
public class VUpload extends SimplePanel implements Paintable {
private final class MyFileUpload extends FileUpload {
@Override
public void onBrowserEvent(Event event) {
super.onBrowserEvent(event);
if (event.getTypeInt() == Event.ONCHANGE) {
if (immediate && fu.getFilename() != null
&& !"".equals(fu.getFilename())) {
submit();
}
} else if (event.getTypeInt() == Event.ONFOCUS) {
// IE and user has clicked on hidden textarea part of upload
// field. Manually open file selector, other browsers do it by
// default.
fireNativeClick(fu.getElement());
// also remove focus to enable hack if user presses cancel
// button
fireNativeBlur(fu.getElement());
}
}
}
public static final String CLASSNAME = "v-upload";
/**
* FileUpload component that opens native OS dialog to select file.
*/
FileUpload fu = new MyFileUpload();
Panel panel = new FlowPanel();
UploadIFrameOnloadStrategy onloadstrategy = GWT
.create(UploadIFrameOnloadStrategy.class);
ApplicationConnection client;
private String paintableId;
/**
* Button that initiates uploading
*/
private final VButton submitButton;
/**
* When expecting big files, programmer may initiate some UI changes when
* uploading the file starts. Bit after submitting file we'll visit the
* server to check possible changes.
*/
private Timer t;
/**
* some browsers tries to send form twice if submit is called in button
* click handler, some don't submit at all without it, so we need to track
* if form is already being submitted
*/
private boolean submitted = false;
private boolean enabled = true;
private boolean immediate;
private Hidden maxfilesize = new Hidden();
private FormElement element;
private com.google.gwt.dom.client.Element synthesizedFrame;
private int nextUploadId;
public VUpload() {
super(com.google.gwt.dom.client.Document.get().createFormElement());
element = getElement().cast();
setEncoding(getElement(), FormPanel.ENCODING_MULTIPART);
element.setMethod(FormPanel.METHOD_POST);
setWidget(panel);
panel.add(maxfilesize);
panel.add(fu);
submitButton = new VButton();
submitButton.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
if (immediate) {
// fire click on upload (eg. focused button and hit space)
fireNativeClick(fu.getElement());
} else {
submit();
}
}
});
panel.add(submitButton);
setStyleName(CLASSNAME);
}
private static native void setEncoding(Element form, String encoding)
/*-{
form.enctype = encoding;
// For IE6
form.encoding = encoding;
}-*/;
public void updateFromUIDL(UIDL uidl, ApplicationConnection client) {
if (client.updateComponent(this, uidl, true)) {
return;
}
if (uidl.hasAttribute("notStarted")) {
t.schedule(400);
return;
}
setImmediate(uidl.getBooleanAttribute("immediate"));
this.client = client;
paintableId = uidl.getId();
nextUploadId = uidl.getIntAttribute("nextid");
element.setAction(client.getAppUri());
submitButton.setText(uidl.getStringAttribute("buttoncaption"));
fu.setName(paintableId + "_file");
if (uidl.hasAttribute("disabled") || uidl.hasAttribute("readonly")) {
disableUpload();
} else if (!uidl.getBooleanAttribute("state")) {
// Enable the button only if an upload is not in progress
enableUpload();
ensureTargetFrame();
}
}
private void setImmediate(boolean booleanAttribute) {
if (immediate != booleanAttribute) {
immediate = booleanAttribute;
if (immediate) {
fu.sinkEvents(Event.ONCHANGE);
fu.sinkEvents(Event.ONFOCUS);
}
}
setStyleName(getElement(), CLASSNAME + "-immediate", immediate);
}
private static native void fireNativeClick(Element element)
/*-{
element.click();
}-*/;
private static native void fireNativeBlur(Element element)
/*-{
element.blur();
}-*/;
protected void disableUpload() {
submitButton.setEnabled(false);
if (!submitted) {
// Cannot disable the fileupload while submitting or the file won't
// be submitted at all
fu.getElement().setPropertyBoolean("disabled", true);
}
enabled = false;
}
protected void enableUpload() {
submitButton.setEnabled(true);
fu.getElement().setPropertyBoolean("disabled", false);
enabled = true;
}
/**
* Re-creates file input field and populates panel. This is needed as we
* want to clear existing values from our current file input field.
*/
private void rebuildPanel() {
panel.remove(submitButton);
panel.remove(fu);
fu = new MyFileUpload();
fu.setName(paintableId + "_file");
fu.getElement().setPropertyBoolean("disabled", !enabled);
panel.add(fu);
panel.add(submitButton);
if (immediate) {
fu.sinkEvents(Event.ONCHANGE);
}
}
/**
* Called by JSNI (hooked via {@link #onloadstrategy})
*/
@SuppressWarnings("unused")
private void onSubmitComplete() {
/* Needs to be run dereferred to avoid various browser issues. */
DeferredCommand.addCommand(new Command() {
public void execute() {
if (client != null) {
if (t != null) {
t.cancel();
}
VConsole.log("VUpload:Submit complete");
client.sendPendingVariableChanges();
}
rebuildPanel();
submitted = false;
enableUpload();
if (!isAttached()) {
/*
* Upload is complete when upload is already abandoned.
*/
cleanTargetFrame();
}
}
});
}
private void submit() {
if (fu.getFilename().length() == 0 || submitted || !enabled) {
VConsole.log("Submit cancelled (disabled, no file or already submitted)");
return;
}
// flush possibly pending variable changes, so they will be handled
// before upload
client.sendPendingVariableChanges();
element.submit();
submitted = true;
VConsole.log("Submitted form");
disableUpload();
/*
* Visit server a moment after upload has started to see possible
* changes from UploadStarted event. Will be cleared on complete.
*/
t = new Timer() {
@Override
public void run() {
VConsole.log("Visiting server to see if upload started event changed UI.");
client.updateVariable(paintableId, "pollForStart",
nextUploadId, true);
}
};
t.schedule(800);
}
@Override
protected void onAttach() {
super.onAttach();
if (client != null) {
ensureTargetFrame();
}
}
private void ensureTargetFrame() {
if (synthesizedFrame == null) {
// Attach a hidden IFrame to the form. This is the target iframe to
// which
// the form will be submitted. We have to create the iframe using
// innerHTML,
// because setting an iframe's 'name' property dynamically doesn't
// work on
// most browsers.
DivElement dummy = Document.get().createDivElement();
dummy.setInnerHTML("<iframe src=\"javascript:''\" name='"
+ getFrameName()
+ "' style='position:absolute;width:0;height:0;border:0'>");
synthesizedFrame = dummy.getFirstChildElement();
Document.get().getBody().appendChild(synthesizedFrame);
element.setTarget(getFrameName());
onloadstrategy.hookEvents(synthesizedFrame, this);
}
}
private String getFrameName() {
return paintableId + "_TGT_FRAME";
}
@Override
protected void onDetach() {
super.onDetach();
if (!submitted) {
cleanTargetFrame();
}
}
private void cleanTargetFrame() {
if (synthesizedFrame != null) {
Document.get().getBody().removeChild(synthesizedFrame);
onloadstrategy.unHookEvents(synthesizedFrame);
synthesizedFrame = null;
}
}
}