Develop Reference

How to open a generated PDF in vaadin?

In my vaadin application I have a Table with an additional column containing a print Button. The Button calls the following util method to create a pdf and open it in a new window (ui parameter is the button):
public static void printPDF(Offer offer, AbstractComponent ui) throws IOException, DocumentException, TemplateException {
// ... create PDF
FileResource resource = new FileResource(pdfFile);
BrowserWindowOpener opener = new BrowserWindowOpener(resource);
opener.setFeatures("");
opener.extend(ui);
}
Now clicking the button the first time does not work. Clicking it the second time works. Clicking it the third time, opens two windows. This increases on every further click.
I also want to open the pdf using the context menu e.g.
table.addActionHandler(new Handler()...
There I don't even have a button to extend. I would prefer to, not use the .extend() part and just open a new window. How can I do that?
EDIT: This blocks the button from opening mulitple instances, still not a nice solution and the first click does not work.
Collection<Extension> extensions = ui.getExtensions();
for (Extension e : extensions) {
if (e instanceof BrowserWindowOpener) {
((BrowserWindowOpener) e).setResource(resource);
return;
}
}
I guess I would need to create a BrowserWindowOpener for every print Button in my Table.
Not a very clean solution, the table may contain lots of rows which would create a lot of BrowserWindowOpener instances which will never be used. The context menu problem would not be solved as well.
EDIT2: This is the other solution I tried:
ResourceReference rr = ResourceReference.create(resource, ui, "print");
Page.getCurrent().open(rr.getURL(), "blank_");
Here I get the following error:
Button (175) did not handle connector request for
print/2016_9090_R_1634500091131558445.pdf

You can use the FileDownloader to achieve what you want.
FileResource resource = new FileResource(pdfFile);
FileDownloader downloader = new FileDownloader(resource);
Button pdf= new Button("Download PDF");
downloader.extend(pdf);

Use this code
Window window = new Window();
((VerticalLayout) window.getContent()).setSizeFull();
window.setResizable(true);
window.setCaption("Exemplo PDF");
window.setWidth("800");
window.setHeight("600");
window.center();
StreamSource s = new StreamResource.StreamSource() {
#Override
public InputStream getStream() {
try {
File f = new File("C:/themes/repy.pdf");
FileInputStream fis = new FileInputStream(f);
return fis;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
};
StreamResource r = new StreamResource(s, "repy.pdf", mainLayout.getApplication());
Embedded e = new Embedded();
e.setSizeFull();
e.setType(Embedded.TYPE_BROWSER);
r.setMIMEType("application/pdf");
e.setSource(r);
window.addComponent(e);
getMainWindow().addWindow(window);

Cannot access UI elements inside vaadin FileUpload FinishListener

I am trying to provide capability to upload file in my vaadin application
protected Upload questionImageUpload = new Upload("Upload question", questionReceiver);
questionImageUpload.addFinishedListener(new Upload.FinishedListener() {
#Override
public void uploadFinished(Upload.FinishedEvent event) {
boolean hasLock = VaadinSession.getCurrent().hasLock();
button.setEnabled(false);
}
});
But, in my FinishListener.uploadFinished(), if I modify some UI element (in above, I disable a button), the modification does not get applied.
I assumed that this method may be invoked in a non UI thread so I checked whether VaadinSession is available by putting a breakpoint in uploadFinished above. But, VaadinSession.getCurrent() didn't return null. Also hasLock is also true.
What could be the reason?
I am running this vaadin application on Google App Engine (still running locally inside IntelliJ IDEA). Could that be the reason behind this?

File upload is done as a POST request to the server, containing the file data. When the upload is complete, Upload.FinishedListeners are called at the end of that POST request. While all thread locals are set up correctly, this is not a UI update request (or UIDL request) and the response which is sent to the browser only contains a text that informs the browser that the upload finished. Any UI updates done will be queued until another request asks for them.
Because of this, you need to either use #Push, so that the UI changes are pushed immediately to the client through the push channel, or enable polling at the latest when starting the upload, so that the poll request will pick up the UI changes.

I actually accomplish what you want to do with a SuccedListener. I have a code which updates an embedded component with picture uploaded. You can look at the code and take a cue from it. It can also disable the button. You can correct it not optimised but it works
public class PicUploader extends Upload implements SucceededListener, Receiver {
private static final long serialVersionUID = 1L;
File file;
public String fileName;
final String LOCATION = "/home/###";
Embedded image = new Embedded();
TextField field;
public PicUploader(Embedded image, String caption) {
this.image = image;
this.addSucceededListener(this);
this.setReceiver(this);
this.setCaption(caption);
this.setIcon(FontAwesome.UPLOAD);;
}
public PicUploader(Embedded image, TextField field) {
this.image = image;
this.addSucceededListener(this);
this.setReceiver(this);
this.field = field;
this.setButtonCaption(""+FontAwesome.UPLOAD);
this.setIcon(FontAwesome.UPLOAD);;
}
#Override
public OutputStream receiveUpload(String filename, String mimeType) {
// TODO Auto-generated method stub
FileOutputStream stream = null;
try {
file = new File(LOCATION
+ "/Pictures/"
+ System.currentTimeMillis()
+ filename.substring(filename.length() - 4,
filename.length()));
fileName = file.getName();
System.out.println("This is the file name " + filename);
stream = new FileOutputStream(file);
} catch (FileNotFoundException ex) {
ex.printStackTrace();
}
return stream;
}
#Override
public void uploadSucceeded(SucceededEvent event) {
// TODO Auto-generated method stub
image.setSource(new FileResource(file));
image.setVisible(true);
image.setWidth("150");
image.setHeight("200");
// float ratio = image.getHeight()/image.getWidth();
// image.setWidth(""+image.getWidth());
// image.setHeight(""+image.getHeight());
// field.setValue(getFileName());
this.setEnabled(false);
}
public String getFileName() {
return fileName;
}
}

passing parameters from javascript to gwt?

I am new to Gwt,i m implementing a webclipper project so my task to send some parameters from javascript file to Gwt so that i will be able to make the connection with my couchdb database but i am getting a problem in passing parameters like title, url ,and summary from webpage to Gwt n then couchdb.The following code is my javascript code:-
function onPageInfo(o) {
document.getElementById('title').value = o.title;
document.getElementById('url').value = o.url;
document.getElementById('summary').innerText = o.summary;
}
// Global reference to the status display SPAN
var statusDisplay = null;
// POST the data to the server using XMLHttpRequest
function addBookmark() {
// Cancel the form submit
event.preventDefault();
// The URL to POST our data to
var postUrl = "http://127.0.0.1:8888/practice.html? gwt.codesvr=127.0.0.1:9997&gwt.codesvr=127.0.0.1:9997/?title=1&url=2&summary=3";
// Set up an asynchronous AJAX POST request
var xhr = new XMLHttpRequest();
xhr.open('POST', postUrl, true);
// Prepare the data to be POSTed
var title = encodeURIComponent(document.getElementById('title').value);
var url = encodeURIComponent(document.getElementById('url').value);
var summary = encodeURIComponent(document.getElementById('summary').value);
var tags = encodeURIComponent(document.getElementById('tags').value);
var params = 'title=' + title +
'&url=' + url +
'&summary=' + summary +
'&tags=' + tags;
// Replace any instances of the URLEncoded space char with +
params = params.replace(/%20/g, '+');
// Set correct header for form data
xhr.setRequestHeader('Content-type', 'application/json');
// Handle request state change events
xhr.onreadystatechange = function() {
// If the request completed
if (xhr.readyState == 4) {
statusDisplay.innerHTML = '';
if (xhr.status == 200) {
// If it was a success, close the popup after a short delay
statusDisplay.innerHTML = 'Saved!';
window.setTimeout(window.close, 1000);
} else {// Show what went wrong
statusDisplay.innerHTML = 'Error saving: ' + xhr.statusText;
}
}
};
// Send the request and set status
xhr.send(params);
statusDisplay.innerHTML = 'Saving...';
}
// When the popup HTML has loaded
window.addEventListener('load', function(evt) {
// Handle the bookmark form submit event with our addBookmark function
document.getElementById('addbookmark').addEventListener('submit', addBookmark);
// Cache a reference to the status display SPAN
statusDisplay = document.getElementById('status-display');
// Call the getPageInfo function in the background page, injecting content_script.js
// into the current HTML page and passing in our onPageInfo function as the callback
chrome.extension.getBackgroundPage().getPageInfo(onPageInfo);
});
Thanks.....

You can call a function defined in a java file (of GWT client module) by exporting that function. Let's assume there is a class A.java which is also your entry point class. This class contains someMethod() which you need to call from javascript passing some parameters. The content of your class A would be something like
public class A implements EntryPoint {
public static functionExported = false;
public void onModuleLoad() {
ExportToBeCalledFromJs();
// other code goes here
}
public static native void ExportToBeCalledFromJs() /*-{
$wnd.toBeCalledFromJs = $entry(function(s1, s2) {
return #com.practice.gwt.client.A::someFunction();
});
#com.practice.gwt.client.A:functionExported = true;
}-*/;
}
Above code exports the function and makes it available to javascript. You can simply call toBeCalledFromJs(param1, param2) fromyour js where param1 would substitute s1 and param2 would substitute s2. If you wish to add more parameters you can modify $entry(function(s1, s2) in the code above.

How to access jtextPane in a different form?

I am developing an application where, when I select a value(file) from list it should be opened in jTextPane of a different form. I am using two panels one is mainpanel where my list is shown and one is ExcelSheet, when i click on a list value then mainpanel is closed and new form ExcelSheet is displayed but not the content of doc file in jTextPane.
XWPFWordExtractor extractor=null;
File file=null;
String str=(String) list.getSelectedValue();
mainPanel.setVisible(false);
new ExcelSheet().setVisible(true);
ExcelSheet obj=new ExcelSheet();
try {
file=new File("C:\\Users\\Siddique Ansari\\Documents\\CV Parser\\"+str);
FileInputStream fis=new FileInputStream(file.getAbsolutePath());
XWPFDocument document=new XWPFDocument(fis);
extractor = new XWPFWordExtractor(document);
String fileData = extractor.getText();
Document doc = obj.jTextPane1.getDocument();
System.out.println(fileData);
doc.insertString(doc.getLength(), fileData, null);
}
catch(Exception exep){exep.printStackTrace();}

Use Action to encapsulate the code that updates the text pane in order to display a given file. You can invoke the action from a ListSelectionListener added to your JList. You can also use the action in a menu item or a toolbar button, as shown here. ImageApp is a related example.
For example, each instance of your action will need the target text pane and file:
class FileAction extends AbstractAction {
JTextPane target;
File file;
public FileAction(JTextPane target, File file) {
this.target = target;
this.file = file;
}
#Override
public void actionPerformed(ActionEvent e) {
// render file in target
}
}

How to print pdf file with wicket and javascript

my wicket apliaction created some pdf file. now I want to add button to print it somethink like this: http://javascript.about.com/library/blprint.htm how I can do it ?

it looks you mix two things together. Your example is a javascript. It is not a PDF, it is just printing your document. It is equal as browser menu File -> Print, but the event is invoked from a javascript that handles button action. You can use the same button as in that example and add #print CSS to your web page to make your document nicely printable.
Also there is another way. If you want to print a PDF document from your application and you generate the PDF from Java code, look the following example for Wicket 1.6:
add(new Link<Void>("myPdfLink") {
private static final long serialVersionUID = 1L;
#Override
public void onClick() {
byte[] data = ... // TODO your data
final ByteArrayInputStream stream = new ByteArrayInputStream(data);
IResourceStream resourceStream = new AbstractResourceStream() {
private static final long serialVersionUID = 1L;
#Override
public InputStream getInputStream() throws ResourceStreamNotFoundException {
return stream;
}
#Override
public void close() throws IOException {
stream.close();
}
#Override
public String getContentType() {
return "application/pdf";
}
};
getRequestCycle().scheduleRequestHandlerAfterCurrent(
new ResourceStreamRequestHandler(resourceStream)
.setFileName("my-pdf-to-download.pdf")
.setContentDisposition(ContentDisposition.ATTACHMENT)
.setCacheDuration(Duration.ONE_SECOND)
);
}
});