Please can anyone help me with my issue - what is the way to know that browserfield2 has finished loading in Blackberry.
I need to set some options after loading. Does browserfield2 have some methods to show that?
Here is some code that will get you started.
BrowserField browserField = new BrowserField();
BrowserFieldListener listener = new BrowserFieldListener() {
public void documentLoaded(BrowserField browserField, Document document) throws Exception
{
// the document has loaded, do something ...
}
}
browserField.addListener( listener );
Related
Inside my application, I'm displaying a website using BrowserField. And when each link inside the site is selected, I need to show loading screen so that the user won't feel blank.
I was able to add the loading screen inside this method
public void documentCreated(BrowserField browserField,
ScriptEngine scriptEngine, Document document)
But the problem is only when connection is established, this method will be called and so there will be a delay before the loading screen is displayed.
So I tried implementing the ProtocolController and adding the loading screen inside this method
public void handleNavigationRequest(BrowserFieldRequest request)
But still, the loading screen is displayed after a small delay (same as when it was under documentCreated method)
This is my code snippet
public void handleNavigationRequest(BrowserFieldRequest request)
throws Exception {
if (!NetworkUtil.isNetworkAvailable()) {
Dialog.inform(Strings.NETWORK_ERROR);
} else {
UiApplication.getUiApplication().invokeAndWait(new Runnable() {
public void run() {
BaseScreen.showLoadingProgress(Strings.LOADING);
}
});
InputConnection ic = handleResourceRequest(request);
browserField.displayContent(ic, request.getURL());
}
}
I tried this outside the thread as well....Still the same is happening. For testing, I added a dialog inside this method and it was coming on the same time I'm clicking any link inside the site. Only this loading screen takes time to load.
Is there any way to make this happen ?
Also, the browser field is taking a bit longer to load the website compared to the native browser.
Am I missing something here ! Please help
I have tried the documentUnloading method as you suggested. But it is not getting triggered. Given below is the code snippet, could you please check what I'm doing wrong here...!!
protected void onUiEngineAttached(boolean attached) {
if (attached) {
BaseScreen.showLoadingProgress(Strings.LOADING);
}
super.onUiEngineAttached(attached);
}
try {
listener = new BrowserFieldListener() {
// Page starts loading...
public void documentCreated(BrowserField browserField,
ScriptEngine scriptEngine, Document document)
{
// show the loading screen
//showLoadingProgress(Strings.LOADING);
}
public void documentError(BrowserField browserField,
Document document) {
hideLoadingProgress();
Dialog.inform(Strings.NETWORK_ERROR);
}
public void documentAborted(BrowserField browserField,
Document document) {
hideLoadingProgress();
Dialog.inform(Strings.NETWORK_ERROR);
}
public void documentUnloading(BrowserField browserField,
Document document) {
BaseScreen.showLoadingProgress(Strings.LOADING);
}
// Page loaded
public void documentLoaded(BrowserField browserField,
Document document) {
// the document has loaded, hide loading popup ...
BaseScreen.hideLoadingProgress();
}
};
} catch (Exception ex) {
Dialog.inform(Strings.NETWORK_ERROR);
}
browserField.addListener(listener);
// add the browser field to a ui manager or screen
add(browserField);
// request the content
browserField.requestContent(URL);
I do this using the BrowserFieldListener (see BrowserFieldListener.html). It is slightly counter intuitive, but I display the loading screen in documentUnloading(), and remove it in documentLoaded(). When I first populate the BrowserField I also push the loading screen, and when the screen with the BrowserField is closed, I make sure the loading screen is popped too. So not a pretty solution, but it works for me.
And yes, in general, the BrowserField is slower than the Browser. I have not found a way round it. However one significant aspect is caching. Look for information on creating your own cache for the BrowserField - there is Thread on here and a KB article on the BB Web site. Sorry can't find them atm, will update when I do.
Update
As found by the OP, the caching article is here.
Further Update
Just to clarify two things:
You must associate the Listener with the BrowserField, using the addListener method.
Assuming you do the usual requestContent() for the initial load of your BrowserField, you will need to push the loading screen yourself because the first method in listener that will be invoked (assuming it has worked of course), will be documentLoaded().
A sample demonstrating how to use the Listener is included here:
listener sample
I am using a ListField Control to display data returned from xml webservice. I want to refresh the ListField or the screen every minute to update the ListField with new records or data.
I tried using the code below but it is not working properly (It is hanging).
public MyApp() {
// Push a screen onto the UI stack for rendering.
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
UiApplication.getUiApplication().pushScreen(new MyScreen());
}
},5000,true);
}
ResponseHandler handler = new ResponseHandler();
ListField listUsers = new ListField(handler.getItem().size());
public MyScreen() {
setTitle("yQAforum");
//Fetch the xml from the web service
String wsReturnString = GlobalV.Fetch_Webservice("myDs");
//Parse returned xml
SAXParserImpl saxparser = new SAXParserImpl();
ByteArrayInputStream stream = new ByteArrayInputStream(wsReturnString.getBytes());
try {
saxparser.parse( stream, handler );
}
catch ( Exception e ) {
response.setText( "Unable to parse response.");
}
//Return vector sze from the handler class
listUsers.setSize(handler.getItem().size());
listUsers.setCallback(this);
listUsers.setEmptyString("No Users found", 0);
add(listUsers);
}
You are attempting to fetch data from your webservice on the UI thread. That's almost always the wrong thing to do.
The UI thread (also known as the main thread) is responsible for drawing the UI, and tracking user actions, like touches, or navigation via a trackpad/trackball. If the UI thread is blocked waiting for a remote web server to respond, it cannot service the UI.
There's a couple changes you should make:
public MyApp() {
// Push a screen onto the UI stack for rendering.
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
UiApplication.getUiApplication().pushScreen(new MyScreen());
}
},5000,true);
}
should be changed to
public MyApp() {
// Push a screen onto the UI stack for rendering.
pushScreen(new MyScreen());
}
The MyApp() constructor will already be called on the UI thread, so there is no need to use invokeLater() to perform the pushScreen() call on the UI thread. It already will be called on the UI thread, if run from within the MyApp constructor. Also, the 5000 msec delay isn't really helpful. This will just delay the startup of your app by 5 seconds, which users will hate.
If you are trying to implement a splash screen, or something similar, when the app starts up, please search stack overflow for "BlackBerry splash screen", and I'm sure you'll find results.
Now, once your MyScreen class is created, you should take care not to fetch web service results from the UI thread. The MyScreen constructor will be run on the UI thread. If you want, you can initiate a web service request on a background thread, once the screen is shown. One way to do that is to use onUiEngineAttached():
protected void onUiEngineAttached(boolean attached) {
if (attached) {
// TODO: you might want to show some sort of animated
// progress UI here, so the user knows you are fetching data
Timer timer = new Timer();
// schedule the web service task to run every minute
timer.schedule(new WebServiceTask(), 0, 60*1000);
}
}
public MyScreen() {
setTitle("yQAforum");
listUsers.setEmptyString("No Users found", 0);
listUsers.setCallback(this);
add(listUsers);
}
private class WebServiceTask extends TimerTask {
public void run() {
//Fetch the xml from the web service
String wsReturnString = GlobalV.Fetch_Webservice("myDs");
//Parse returned xml
SAXParserImpl saxparser = new SAXParserImpl();
ByteArrayInputStream stream = new ByteArrayInputStream(wsReturnString.getBytes());
try {
saxparser.parse( stream, handler );
}
catch ( Exception e ) {
response.setText( "Unable to parse response.");
}
// now, update the UI back on the UI thread:
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
// TODO: record the currently selected, or focused, row
//Return vector sze from the handler class
listUsers.setSize(handler.getItem().size());
// Note: if you don't see the list content update, you might need to call
// listUsers.invalidate();
// here to force a refresh. I can't remember if calling setSize() is enough.
// TODO: set the previously selected, or focused, row
}
});
}
}
You'll need to add some error handling, in case the web service doesn't respond, or takes longer than a minute (you wouldn't want to be making a new request, if the last one hadn't finished).
But, this should get you started.
Note: once you fix the problem with running network code on the UI thread, you may still find that your code doesn't work. There could be problems fetching the web service data. You'll have to debug that. I am only showing you one problem with the code posted. If you still have problems with the web service fetch, post another question (with the UI thread problem fixed). Thanks.
This is the code i m running in my blackberry bold 9900 simulator but the BrowserField just shows the blank white screen and nothing. Is there any problem with my simulator or some setting needs to be done in it. Thanks in advance for help.
public class StartUp extends UiApplication
{
public static void main(String[])
{
StartUp start=new StartUp();
start.enterEventDispatcher();
}
public StartUp()
{
MainScreen screen = new MainScreen();
BrowserField browserField = new BrowserField();;
screen.add(browserField);
pushScreen(screen);
browserField.requestContent("http://www.google.com/news");
}
}
Verify if you have a network connection in your simulator, see this development guide article.
I am using AttachmentDownloadManager class download method to download the email attachments to the device.I am displaying a progress screen while the attachments gets downloaded to device.In the downloadCompleted() event listener method, I am trying to stop/close the progress screen but unable to do so.
Below is the code snippet:
attachmentDownloadMngr = new AttachmentDownloadManager();
attachmentDownloadMngr.download(attachmentBodyPart, null, new IGAEmailAttachmentListener(this));
Below are DownloadProgressListener event listener methods:
public void updateProgress(Object element, int current, int total)
{
synchronized(UiApplication.getEventLock())
{
Ui.getUiEngine().pushGlobalScreen(progressScreen,1,UiEngine.GLOBAL_QUEUE);
}
}
public void downloadCompleted(Object element)
{
synchronized(UiApplication.getEventLock())
{
Ui.getUiEngine().popScreen(progressScreen);
}
}
public void downloadCancelled(Object element)
{
}
progressScreen is instance of PopupScreen where I am displaying a guagefield. The progress screen does not get any events even after the attachment download is completed.
Please help me to solve this issue.
You seem to be pushing a globalscreen every time you get a callback to updateprogress() . I wouldn't do it. I would rather push the globalscreen with the gaugefield when I start the download, and then set the value of gaugefield using gaugeField.setValue(value).
the way you are doing it would mean, the event thread pushes too many screens on to the stack, and I guess it would throw a run time exception and kill your app.
I need to display a splash screen when I app instantiate, I wrote a class for splashScreen based on blackberry develpers knowlwdebase (link).
And its invoked from my following class.My problem is the splashscreen appears only after a deley,How can I solve it,If any one have idea Please help me,Thanks
class Test extends MainScreen{
Test(){
UiApplication.getUiApplication().invokeLater(new Runnable()
{
public void run() {
UiApplication app=(UiApplication)getApplication();
Bitmap image = Bitmap.getBitmapResource("splah.png");
ListView listView = new ListView();
new SplashScreen(app, listView );
}
}
Try synchronized (UiApplication.getEventLock()). It is faster than invokeLater.
Test(){
synchronized (UiApplication.getEventLock()) {
UiApplication app=(UiApplication)getApplication();
Bitmap image = Bitmap.getBitmapResource("splah.png");
ListView listView = new ListView();
new SplashScreen(app, listView );
}
}