How to download images in background in j2me? - java-me

I have one canvas where I am showing one image on center. This image is downloaded by url. Actually there are more images to be downloaded, that means if user clicks RIGHT I have to show next image if LEFT, I have to show another one image from backside. I have array of strings which storing images of url. I want to download previous and next image in background. How to do that?

Following are some of the issues that you need to consider for this requirement to work across a range of devices
What if the image is big compared to the device canvas size ? That is image dimension w * h is very high compared to canvas w * h ?
Can low memory devices load such big images ?
Inconsistent multi-thread model across devices. That is some devices it will allow you create 10 threads while in other it will stop at 2.
Can my application support the fetch image type ? That is I am downloading .JPG / .GIF but my device does not support it.
How to cache the images ? Do you want to load the same image again and again when you navigate to that image ?
Do I use TCP / HTTP / RMI for downloading image content ?
Will this code be portable across different flavors JVM for JavaME ?
and the list continues.....
Keeping in mind the above set of issues that you will land-up with a constructive answer to your problem is to create a network IO manager and a caching manager.
interface NetworkIoItem {
Object sourceComponent;
public void onImageDownload(Image image) {
//Trigger the source
}
}
.
class NetworkIoManager extends Threads {
Vector pendingRequestQueue;
:
:
public void run() {
//Wait on the pending request queue
//Process all the elements in pending request queue
//and again wait on this queue
}
}
.
class CacheManager {
Vector cachedContent;
public boolean checkIfCached() {
//Check in the cachedContent whether
//this image exists if so return true;
}
public Image fetchImage() {
//Check if the image is cached
//if so return this cached image
//else push a NetworkIoItem object to
//NetworkIOManager pending queue
}
}
Now for each image (current, left or right) call the CacheManager.fetchImage(), this method will take care of providing you image either cached or downloaded from server. In the same method if the image is not cached it will add NetworkIoItem objbect to the NetworkIoManager pendingQueue and download it. On completion of download it will trigger NetworkIoItem.onImageDownload(...) method.
You can use J2ME Polish's Touch feature to download a image in the NetworkIoManager
By using this approach you will do asynchronous image fetches to the request URL.

Do something like..
Thread t = new Thread(new Runnable(){
public void run() {
// Your code to download image here as you were doing earlier,
// for previous and next image
}
});
t.start();

Related

Flutter Web - get asset image as File()

I am using a third party library that requires I pass U8IntList to display an image in a PDF. Their examples has me obtain the image in a File and read the bytes out.
PdfBitmap(file.readAsBytesSync())
This system is great when I am obtaining an image from a server, but I want to display an image stored in local assets.
What I tried to implement was this code..
Future<File> getImageFileFromAssets(String path) async {
final byteData = await rootBundle.load('assets/$path');
final file = File('${(await getTemporaryDirectory()).path}/$path');
await file.writeAsBytes(byteData.buffer.asUint8List(byteData.offsetInBytes, byteData.lengthInBytes));
return file;
}
Which returns the error 'No implementation found for method getTemporaryDirectory on channel plugins.flutter.io/path_provider'.
If anyone knows how to get an Asset Image as File on web it would be greatly appreciated.
Why would you want to write byte data to a file just to read it again? Just directly pass your byte data to the constructor that requires it. This should be changed on both your web and mobile implementations as it will end up being far faster.
final byteData = await rootBundle.load('assets/$path');
PdfBitmap(byteData.buffer.asUint8List())

How can I automate the creation and SFTP transfer of a snapshot in Acumatica?

I would like to create a nightly snapshot of certain tables in my SAAS-hosted Acumatica instance and SFTP the resulting XML file to a given location. (I've created a custom Export Mode option for just the tables of interest.)
I would like to do this process through an Acumatica Automation Schedule, a custom Action that I can call through the API, or an API call to existing Acumatica Actions, or some combination of the above.
However, it doesn't appear that these options are available to me:
Automation Scheduling doesn't support snapshot creation (https://feedback.acumatica.com/ideas/ACU-I-570)
I tried adding the Action to create a snapshot to the web service endpoint, but it doesn't appear that I can pass the parameters I would need to manage the pop-ups
Attempting to create a custom Acumatica button, I'm also to struggling to figure out how to raise and manage the pop-ups.
Once I have the snapshot created, I presume I will need to be able to download it locally in order to SFTP it to my desired location; I haven't gotten far enough to know if I invoke the download snapshot button through the API where the resulting file will go.
June,
When I get stuck with stuff that I am unable to trigger with ReST or other integration techniques I generally turn to Selenium as the path of least resistance. I do want to point out I always err on the side of using selenium as a last resort.
I generally like to use the PowerShell selenium module for stuff like this.
Once you have your script working you can wire it into a standard Windows Scheduler real easy.
It may not be the most elegant way to do it but it will certainly get the job done.
if your interested you can get started with this
https://github.com/adamdriscoll/selenium-powershell/blob/master/README.md
Once you get familiar with it you use the chrome inspection tool to dig into the elements that you need to target. the dialog boxes you are after are often found as iframes within the page.
I can share some of my scripts to help you get started if you want to try this route.
I hope this helps.
Robert
I ended up creating a simple console application since it was more in line with our other applications and I have more familiarity with C# than with PowerShell. Robert, your project was invaluable to figuring out how to reference the trickier elements.
I expect to set up scheduled tasks that will call my application with the method name of each step, with appropriate delays between each -- creating the snapshot takes about 25 minutes, for example. There are separate methods to create the snapshot, download the snapshot, delete the snapshot, and next I'm working on SFTPing the downloaded snapshot to its end destination. I put in sleeps to allow time for the website to catch up; there are Waits and WaitForExpectedCondition methods available but I didn't get into them in this quick and dirty version.
Here's the guts of my code. (I added WebDriver and ChromeDriver to the application via Nuget.)
using System;
using System.Collections.Generic;
using System.Linq;
using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
using System.Threading;
namespace InfiniteExport
{
class Program
{
static string connectorInfo;
static void Main(string[] args)
{
string method = "";
if (args.Count() >= 1)
{
method = args[0].ToLower();
}
IWebDriver driver = new ChromeDriver();
try
{
switch (method)
{
case "createsnapshot":
Login(driver);
CreateSnapshot(driver);
break;
case "downloadsnapshot":
Login(driver);
DownloadSnapshot(driver);
break;
case "deletesnapshot":
Login(driver);
DeleteSnapshot(driver);
break;
default:
break;
}
}
catch (Exception e)
{
throw e;
}
finally
{
driver.Quit();
}
}
static void Login(IWebDriver driver)
{
//This login actually results in a 404 error because there's no redirect embedded in it, but the login itself is successful and creates the session used by the next method navigation
driver.Navigate().GoToUrl(InfiniteExport.Properties.Settings.Default.BaseAcumaticaURL + "/Frames/Login.aspx");
driver.FindElement(By.Id("form1")).Click();
driver.FindElement(By.Id("txtUser")).SendKeys(InfiniteExport.Properties.Settings.Default.AcumaticaUserName);
driver.FindElement(By.Id("txtPass")).SendKeys(InfiniteExport.Properties.Settings.Default.AcumaticaPassword);
driver.FindElement(By.Id("btnLogin")).Click();
driver.Manage().Window.Maximize();
Thread.Sleep(5000);
}
static void CreateSnapshot(IWebDriver driver)
{
driver.Navigate().GoToUrl(#InfiniteExport.Properties.Settings.Default.BaseAcumaticaURL + "/Main?ScreenId=SM203520&_CompanyID=2");
Thread.Sleep(2000);
driver.SwitchTo().Frame("main");
//Click the #$##%*! unnamed create snapshot button
driver.FindElement(By.CssSelector(".toolsBtn[data-cmd=exportSnapshotCommand]")).Click();
Thread.Sleep(2000);
//Switch to the modal popup to start clicking items on it (this is the "Warning not in maintenance mode" popup)
driver.SwitchTo().ActiveElement();
driver.FindElement(By.Id("messageBox_0")).Click();
Thread.Sleep(2000);
//Switch to the modal popup with the export options
driver.SwitchTo().ActiveElement();
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_frmExportSnapshot_edDescription")).SendKeys("InfiniteExport");
//Select the dropdown option for the InfiniteExport
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_frmExportSnapshot_edExportMode_text")).Click();
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_frmExportSnapshot_edExportMode_text")).SendKeys("InfiniteExport");
Thread.Sleep(2000);
driver.FindElement(By.ClassName("ddSelection")).Click();
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_frmExportSnapshot_chkPrepare")).Click();
//Select the dropdown option for XML
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_frmExportSnapshot_edPrepareMode")).Click();
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_frmExportSnapshot_edPrepareMode_text")).SendKeys("XML");
Thread.Sleep(2000);
driver.FindElement(By.ClassName("ddSelection")).Click();
Thread.Sleep(2000);
//Click the OK button to start the export
driver.FindElement(By.Id("ctl00_phF_pnlExportSnapshot_btnExportSnapshotOK")).Click();
//Wait long enough for the process to start, then quit and come back later to download
Thread.Sleep(10000);
}
static void DownloadSnapshot(IWebDriver driver)
{
driver.Navigate().GoToUrl(#InfiniteExport.Properties.Settings.Default.BaseAcumaticaURL + "/Main?ScreenId=SM203520&_CompanyID=2");
Thread.Sleep(2000);
driver.SwitchTo().Frame("main");
//Unless this is made fancier, it will download the active grid row, which is the most recent snapshot created
driver.FindElement(By.CssSelector(".toolsBtn[data-cmd=downloadSnapshotCommand]")).Click();
Thread.Sleep(10000);
}
static void DeleteSnapshot(IWebDriver driver)
{
driver.Navigate().GoToUrl(#InfiniteExport.Properties.Settings.Default.BaseAcumaticaURL + "/Main?ScreenId=SM203520&_CompanyID=2");
Thread.Sleep(2000);
driver.SwitchTo().Frame("main");
//Unless this is made fancier, it will delete the active grid row, which is the most recent snapshot created
driver.FindElement(By.CssSelector(".toolsBtn[data-cmd=Delete]")).Click();
Thread.Sleep(2000);
driver.FindElement(By.CssSelector(".toolsBtn[data-cmd=saveCompanyCommand]")).Click();
Thread.Sleep(10000);
}
}
}

How to prevent the screen from locking on UWP 10

I want to prevent the phone to lock if the user didnt interact with the phone for some time.
In win8 phone development i used the PhoneApplicationService.UserIdleDetectionMode Property. Unfortunately i cannot find anything alike for win 10 universal app.
Any suggestions?
Simple Answer
DisplayRequest class
var displayRequest = new DisplayRequest();
displayRequest.RequestActive(); //to request keep display on
displayRequest.RequestRelease(); //to release request of keep display on
Detailed Answer
Using display requests to keep the display on consumes a lot of power. Use these guidelines for best app behavior when using display requests.
Use display requests only when required, that is, times when no user input is expected but the display should remain on. For example, during full screen presentations or when the user is reading an e-book.
Release each display request as soon as it is no longer required.
Release all display requests when the app is suspended. If the display is still required to remain on, the app can create a new display request when it is reactivated.
To Request keep display on
private void Activate_Click(object sender, RoutedEventArgs e)
{
if (g_DisplayRequest == null)
{
g_DisplayRequest = new DisplayRequest();
}
if (g_DisplayRequest != null)
{
// This call activates a display-required request. If successful,
// the screen is guaranteed not to turn off automatically due to user inactivity.
g_DisplayRequest.RequestActive();
drCount += 1;
}
}
To release request of keep display on
private void Release_Click(object sender, RoutedEventArgs e)
{
// This call de-activates the display-required request. If successful, the screen
// might be turned off automatically due to a user inactivity, depending on the
// power policy settings of the system. The requestRelease method throws an exception
// if it is called before a successful requestActive call on this object.
if (g_DisplayRequest != null)
{
g_DisplayRequest.RequestRelease();
drCount -= 1;
}
}
References - Prevent the screen from locking on Universal Windows Platform
Hope it help someone!!
You want the DisplayRequest class in Windows 10.

Taking a screenshot of a scene or a portion of a scene in JavaFx 2.2

I've managed to make a WritableImage using
WritableImage snapshot = obj.getScene().snapshot(null);
Now I would like to output this screenshot on a pdf file. I've already managed to output text to a pdf using Apache pdfbox library using the following code:
PDDocument doc = null;
PDPage page = null;
try{
doc = new PDDocument();
page = new PDPage();
doc.addPage(page);
PDFont font = PDType1Font.HELVETICA_BOLD;
PDPageContentStream content = new PDPageContentStream(doc, page);
content.beginText();
content.setFont( font, 12 );
content.moveTextPositionByAmount( 100, 700 );
content.drawString("Hello World");
content.endText();
content.close();
doc.save("PDFWithText.pdf");
doc.close();
} catch (Exception e){
System.out.println(e);
}
How can I do this when using WritableImage rather that using basic String texts?
Also, how can I take a screenshot of certain nodes within a scene?
Thanks
Taking a screenshot of a scene
You already have working code for this in your question.
WritableImage snapshot = stage.getScene().snapshot(null);
Taking a screenshot of a . . . portion of a scene in JavaFx 2.2
Taking a snapshot of Node is similar to taking snapshot of a Scene, you just use the snapshot methods on the Node rather than the scene. First place your Node in a Scene, and then snapshot the Node.
WritableImage snapshot = node.snapshot(null, null);
The first parameter which may be passed to the node.snapshot call is some configuration for SnapshotParameters (which you probably don't need, but you can investigate them to see if they are required or useful for your case).
Now I would like to output this screenshot on a pdf file. How can I do this when using WritableImage rather that using basic String texts?
I have not used the pdfbox toolkit you reference in your question. Likely the toolkit works with awt based images rather than JavaFX images, so you will need to convert your JavaFX snapshot image to an awt buffered image using SwingFXUtils.fromFXImage.
To actually get the awt encoded image into a pdf file, consult the documentation for your pdfbox toolkit. Kasas's answer to Add BufferedImage to PDFBox document would seem to provide a code snippet for this operation. Looks like the relevant code (and I haven't tried this) is:
PDPageContentStream content = new PDPageContentStream(doc, page);
PDXObjectImage ximage = new PDJpeg(doc, bufferedImage);
content.drawImage(ximage, x, y);

Blackberry Audio Recording Sample Code

Does anyone know of a good repository to get sample code for the BlackBerry? Specifically, samples that will help me learn the mechanics of recording audio, possibly even sampling it and doing some on the fly signal processing on it?
I'd like to read incoming audio, sample by sample if need be, then process it to produce a desired result, in this case a visualizer.
RIM API contains JSR 135 Java Mobile Media API for handling audio & video content.
You correct about mess on BB Knowledge Base. The only way is browse it, hoping they'll not going to change site map again.
It's Developers->Resources->Knowledge Base->Java API's&Samples->Audio&Video
Audio Recording
Basically it's simple to record audio:
create Player with correct audio encoding
get RecordControl
start recording
stop recording
Links:
RIM 4.6.0 API ref: Package javax.microedition.media
How To - Record Audio on a BlackBerry smartphone
How To - Play audio in an application
How To - Support streaming audio to the media application
How To - Specify Audio Path Routing
How To - Obtain the media playback time from a media application
What Is - Supported audio formats
What Is - Media application error codes
Audio Record Sample
Thread with Player, RecordControl and resources is declared:
final class VoiceNotesRecorderThread extends Thread{
private Player _player;
private RecordControl _rcontrol;
private ByteArrayOutputStream _output;
private byte _data[];
VoiceNotesRecorderThread() {}
private int getSize(){
return (_output != null ? _output.size() : 0);
}
private byte[] getVoiceNote(){
return _data;
}
}
On Thread.run() audio recording is started:
public void run() {
try {
// Create a Player that captures live audio.
_player = Manager.createPlayer("capture://audio");
_player.realize();
// Get the RecordControl, set the record stream,
_rcontrol = (RecordControl)_player.getControl("RecordControl");
//Create a ByteArrayOutputStream to capture the audio stream.
_output = new ByteArrayOutputStream();
_rcontrol.setRecordStream(_output);
_rcontrol.startRecord();
_player.start();
} catch (final Exception e) {
UiApplication.getUiApplication().invokeAndWait(new Runnable() {
public void run() {
Dialog.inform(e.toString());
}
});
}
}
And on thread.stop() recording is stopped:
public void stop() {
try {
//Stop recording, capture data from the OutputStream,
//close the OutputStream and player.
_rcontrol.commit();
_data = _output.toByteArray();
_output.close();
_player.close();
} catch (Exception e) {
synchronized (UiApplication.getEventLock()) {
Dialog.inform(e.toString());
}
}
}
Processing and sampling audio stream
In the end of recording you will have output stream filled with data in specific audio format. So to process or sample it you will have to decode this audio stream.
Talking about on the fly processing, that will be more complex. You will have to read output stream during recording without record commiting. So there will be several problems to solve:
synch access to output stream for Recorder and Sampler - threading issue
read the correct amount of audio data - go deep into audio format decode to find out markup rules
Also may be useful:
java.net: Experiments in Streaming Content in Java ME by Vikram Goyal
While not audio specific, this question does have some good "getting started" references.
Writing Blackberry Applications
I spent ages trying to figure this out too. Once you've installed the BlackBerry Component Packs (available from their website), you can find the sample code inside the component pack.
In my case, once I had installed the Component Packs into Eclipse, I found the extracted sample code in this location:
C:\Program
Files\Eclipse\eclipse3.4\plugins\net.rim.eide.componentpack4.5.0_4.5.0.16\components\samples
Unfortunately when I imported all that sample code I had a bunch of compile errors. To workaround that I just deleted the 20% of packages with compile errors.
My next problem was that launching the Simulator always launched the first sample code package (in my case activetextfieldsdemo), I couldn't get it to run just the package I am interested in. Workaround for that was to delete all the packages listed alphabetically before the one I wanted.
Other gotchas:
-Right click on the project in Eclipse and select Activate for BlackBerry
-Choose BlackBerry -> Build Configurations... -> Edit... and select your new project so it builds.
-Make sure you put your BlackBerry source code under a "src" folder in the Eclipse project, otherwise you might hit build issues.

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