I'm new to java. I want to embed a browser in a JFrame. I used a JEditorPane to display the HTML, but it still doesn't display the page correctly. It shows the page, but things are out of place. My biggest concern is that Java applets that are embedded in web pages are not showing up in my custom browser. I'm probably not using JEditorPane correctly. Here is my code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.net.*;
import java.io.*;
public class Frame1 extends JFrame implements ActionListener
{
private JEditorPane editorPane;
private JTextField addressField;
private JButton goButton;
private JLabel label;
public Frame1() {
super("Frame1");
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch(Exception e) {
System.out.println("Unablet to set look and feel.");
}
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
label = new JLabel("Enter URL. Must include http://");
// setup editor pane
editorPane = new JEditorPane();
editorPane.setEditable(false);
URL url = null;
try {
url = new URL("http://www.cut-the-knot.org/SimpleGames/FrogsAndToads2d.shtml");
} catch (MalformedURLException e) {
}
if (url != null) {
try {
editorPane.setPage(url);
} catch (IOException e) {
label.setText("Attempted to read a bad URL: " + url);
}
} else {
label.setText("String specifies an unknown protocol.");
}
// put editor pane in a scroll pane
JScrollPane editorScrollPane = new JScrollPane(editorPane);
editorScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
editorScrollPane.setPreferredSize(new Dimension(250, 145));
editorScrollPane.setMinimumSize(new Dimension(10, 10));
// setup everything in southPanel.
// southPanel > addressBar + label> addressField + goButton
addressField = new JTextField(30);
goButton = new JButton("Go");
goButton.addActionListener(this);
JPanel addressBar = new JPanel();
JPanel southPanel = new JPanel(new GridLayout(2, 1));
addressBar.add(addressField);
addressBar.add(goButton);
southPanel.add(addressBar);
southPanel.add(label);
// add everything to JFrame
setLayout(new BorderLayout());
add(southPanel, BorderLayout.SOUTH);
add(editorScrollPane, BorderLayout.CENTER);
setSize(500, 500);
setVisible(true);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == goButton) {
URL url = null;
try {
url = new URL(addressField.getText());
} catch (MalformedURLException murle) {
}
if (url != null) {
try {
editorPane.setPage(url);
} catch (IOException ioe) {
label.setText("Attempted to read a bad URL: " + url);
}
} else {
label.setText("String specifies an unknown protocol.");
}
}
}
public static void main(String[] args) {
new Frame1();
}
}
you should consider a swing java embedded browser. Examples of this are:
lobo java browser
DJ Project Native Swing
you could also condsider SWT Browser
those are all free open source java embeded browsers.
hope this helps.
Related
I have my download manager, and it work perfect if I try to download a file. But I have a problem.
I have 4 CardView in my activity and I set it onClickListener, so when I click one CardView it will download the file.
Here is the code to call the download function
cardviewR1 = findViewById(R.id.card_viewR1);
cardviewR1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
pDialogDL = new ProgressDialog(this);
pDialogDL.setMessage("A message");
pDialogDL.setIndeterminate(true);
pDialogDL.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pDialogDL.setCancelable(true);
final DownloadTask downloadTask = new DownloadTask(this);
downloadTask.execute(R1Holder);
pDialogDL.setOnCancelListener(new DialogInterface.OnCancelListener() {
#Override
public void onCancel(DialogInterface dialog) {
downloadTask.cancel(true);
}
});
}
});
and here is the download function
private class DownloadTask extends AsyncTask<String, Integer, String> {
private Context context;
private PowerManager.WakeLock mWakeLock;
public DownloadTask(Context context) {
this.context = context;
}
#Override
protected String doInBackground(String... sUrl) {
InputStream input = null;
OutputStream output = null;
HttpURLConnection connection = null;
try {
URL url = new URL(sUrl[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
// expect HTTP 200 OK, so we don't mistakenly save error report
// instead of the file
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
return "Server returned HTTP " + connection.getResponseCode()
+ " " + connection.getResponseMessage();
}
// this will be useful to display download percentage
// might be -1: server did not report the length
int fileLength = connection.getContentLength();
// download the file
input = connection.getInputStream();
output = new FileOutputStream(Environment.getExternalStorageDirectory().getPath()+"/"+getString(R.string.r1)+"_"+NameHolder+".zip");
byte data[] = new byte[4096];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
// allow canceling with back button
if (isCancelled()) {
input.close();
return null;
}
total += count;
// publishing the progress....
if (fileLength > 0) // only if total length is known
publishProgress((int) (total * 100 / fileLength));
output.write(data, 0, count);
}
} catch (Exception e) {
return e.toString();
} finally {
try {
if (output != null)
output.close();
if (input != null)
input.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
}
return null;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
// take CPU lock to prevent CPU from going off if the user
// presses the power button during download
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
getClass().getName());
mWakeLock.acquire();
pDialogDL.show();
}
#Override
protected void onProgressUpdate(Integer... progress) {
super.onProgressUpdate(progress);
// if we get here, length is known, now set indeterminate to false
pDialogDL.setIndeterminate(false);
pDialogDL.setMax(100);
pDialogDL.setProgress(progress[0]);
}
#Override
protected void onPostExecute(String result) {
mWakeLock.release();
pDialogDL.dismiss();
if (result != null)
Toast.makeText(context, "Download error: " + result, Toast.LENGTH_LONG).show();
else
Toast.makeText(context, "File downloaded", Toast.LENGTH_SHORT).show();
}
}
The code work in my app, but the problem is, when I try to add second CardView which is like this
cardviewR2 = findViewById(R.id.card_viewR2);
cardviewR2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
pDialogDL = new ProgressDialog(this);
pDialogDL.setMessage("A message");
pDialogDL.setIndeterminate(true);
pDialogDL.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pDialogDL.setCancelable(true);
final DownloadTask downloadTask = new DownloadTask(this);
downloadTask.execute(R2Holder);
pDialogDL.setOnCancelListener(new DialogInterface.OnCancelListener() {
#Override
public void onCancel(DialogInterface dialog) {
downloadTask.cancel(true);
}
});
}
});
Yes it will download the second file, but it will overwrite the first file. I think the problem is right here
output = new FileOutputStream(Environment.getExternalStorageDirectory().getPath()+"/"+getString(R.string.r1)+"_"+NameHolder+".zip");
Anyone can help me with this code?
I need your help, Thanks
Fixed it by create a new Download Class separately in different file with activity, so the AsyncTask will be call again and again
thanks
I want my application to auto-refresh the content in the Vbox from the database. I have started the thread in the initialize method. Why does my Gui freezes. Is there any better way to perform such threading operation for GUI refreshing.
package Messanger.ChatWindow;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.Region;
import javafx.scene.layout.VBox;
import javafx.scene.text.TextAlignment;
import Messanger.Login.Login;
import java.io.IOException;
import Messanger.Settings.Settings;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Platform;
import javafx.concurrent.Service;
import javafx.concurrent.Task;
import javax.swing.JOptionPane;
public class Controller implements Initializable {
Settings set = new Settings();
VBox msg_vbox = new VBox();
#FXML
ScrollPane scrlpane;
#FXML
TextField message;
protected Model md;
public Controller() throws SQLException {
this.md = new Model();
}
#FXML
protected void Settings() {
try {
set.loadView();
} catch (IOException ex) {
Logger.getLogger(Controller.class.getName()).log(Level.SEVERE, null, ex);
}
}
#FXML
protected void Logout() throws IOException {
Login lgin = new Login();
lgin.loadView();
ChatWindow.cW.close();
}
protected synchronized void refreshContent() throws SQLException {
ResultSet messageArry = md.getMessages();
while (messageArry.next()) {
msg_vbox.getChildren().clear();
//new label text with message.
Label set_text = new Label();
set_text.setText(messageArry.getString("username") + " Says: \n" + messageArry.getString("message"));
set_text.setStyle("-fx-padding:10;"
+ "-fx-width:100%;"
+ "-fx-background-color:teal;"
+ " -fx-background-insets: 5;"
+ "-fx-font-size:15;"
+ "-fx-background-radius: 3;");
set_text.setPrefSize(Region.USE_COMPUTED_SIZE, Region.USE_COMPUTED_SIZE);
set_text.setWrapText(true);
set_text.setTextAlignment(TextAlignment.JUSTIFY);
set_text.setPrefWidth(600);
//VBox wrapper
msg_vbox.getChildren().addAll(set_text);
msg_vbox.setPrefWidth(600);
//Further wrapped by ScrollPane
scrlpane.fitToHeightProperty();
scrlpane.setContent(msg_vbox);
scrlpane.setVbarPolicy(ScrollPane.ScrollBarPolicy.NEVER);
scrlpane.vvalueProperty().bind(msg_vbox.heightProperty()); //sets the scroll view to new element.
}
}
#FXML
protected void sendMessage() {
//new label text with message.
Label set_text = new Label();
set_text.setText(Messanger.Login.Controller.SESSION_usrname + " Says: \n" + message.getText());
set_text.setStyle("-fx-padding:10;"
+ "-fx-width:100%;"
+ "-fx-background-color:teal;"
+ " -fx-background-insets: 5;"
+ "-fx-font-size:15;"
+ "-fx-background-radius: 3;");
set_text.setPrefSize(Region.USE_COMPUTED_SIZE, Region.USE_COMPUTED_SIZE);
set_text.setWrapText(true);
set_text.setTextAlignment(TextAlignment.JUSTIFY);
set_text.setPrefWidth(600);
//VBox wrapper
msg_vbox.getChildren().addAll(set_text);
msg_vbox.setPrefWidth(600);
//Further wrapped by ScrollPane
scrlpane.fitToHeightProperty();
scrlpane.setContent(msg_vbox);
scrlpane.setVbarPolicy(ScrollPane.ScrollBarPolicy.NEVER);
scrlpane.vvalueProperty().bind(msg_vbox.heightProperty()); //sets the scroll view to new element.
message.setText("");
}
#FXML
protected void check_key(KeyEvent ae) throws SQLException {
if (ae.getCode().equals(KeyCode.ENTER)) {
if (md.addMessage(Messanger.Login.Controller.SESSION_usrname, message.getText())) {
sendMessage();
} else {
JOptionPane.showMessageDialog(null, "Message Sending failed \n "
+ "Please Check Your Internet Connection", "Error ", JOptionPane.INFORMATION_MESSAGE);
}
}
}
#Override
public void initialize(URL location, ResourceBundle resources) {
scrlpane.setStyle("-fx-background:#32AED8");
scrlpane.setPrefHeight(300);
try {
refreshContent();
} catch (SQLException ex) {
Logger.getLogger(Controller.class.getName()).log(Level.SEVERE, null, ex);
}
Service<Void> service = new Service<Void>() {
#Override
protected Task<Void> createTask() {
return new Task<Void>() {
#Override
protected Void call() throws Exception {
Platform.runLater(new Runnable() {
#Override
public void run() {
while (true) {
try {
refreshContent();
} catch (SQLException ex) {
Logger.getLogger(Controller.class.getName()).log(Level.SEVERE, null, ex);
}
try {
Thread.sleep(100);
} catch (InterruptedException ex) {
Logger.getLogger(Controller.class.getName()).log(Level.SEVERE, null, ex);
}
System.out.println("asd");
}
}
});
return null;
}
};
}
};
service.start();
}
}
As in the code i've started the thread and i want to run the refreshContent method. I've also tried it implementing the Runnable interface. But same problem occurs.
You are creating a new thread. However from this new thread you immediately post a Runnable to be run on the javaFX application thread that is handling the connection to the DB using a infinite loop, so you are blocking the application thread.
To not block the application thread do the long-running parts of the task on a different thread, then use Platform.runLater to update the UI.
Also you probably shouldn't initialize the rows in the result set loop...
private List<Node> refreshedContent() {
List<Node> result = new ArrayList<>();
ResultSet messageArry = md.getMessages();
while (messageArry.next()) {
// initialize nodes not yet attached to a scene
Label set_text = new Label();
set_text.setText(messageArry.getString("username") + " Says: \n" + messageArry.getString("message"));
set_text.setStyle("-fx-padding:10;"
+ "-fx-width:100%;"
+ "-fx-background-color:teal;"
+ " -fx-background-insets: 5;"
+ "-fx-font-size:15;"
+ "-fx-background-radius: 3;");
set_text.setPrefSize(600, Region.USE_COMPUTED_SIZE);
set_text.setWrapText(true);
set_text.setTextAlignment(TextAlignment.JUSTIFY);
result.add(set_text);
}
return result;
}
#Override
protected Void call() throws Exception {
while (true) {
// do long-running operation
List<Node> newContent = refreshedContent();
Platform.runLater(new Runnable() {
#Override
public void run() {
// there should be no need to do this over and over again
// you should move it outside of the task
msg_vbox.setPrefWidth(600);
//scrlpane.fitToHeightProperty(); // does nothing anyway...
scrlpane.setContent(msg_vbox);
scrlpane.setVbarPolicy(ScrollPane.ScrollBarPolicy.NEVER);
scrlpane.vvalueProperty().bind(msg_vbox.heightProperty()); //probably won't work the intended way...
// update ui
msg_vbox.getChildren().setAll(newContent);
}
});
// do more long-running operations
try {
Thread.sleep(100);
} catch (InterruptedException ex) {
Logger.getLogger(Controller.class.getName()).log(Level.SEVERE, null, ex);
}
System.out.println("asd");
}
}
Furthermore:
Consider using ListView
Usually data access is not done from the UI layer. You could do the updates from a data access layer and make the model properties observable and update the ui on changes...
Try avoid recreating the nodes multiple times a second. ListView would help in this case. If you do not want to use a ListView you should try reusing existing Labels as much as possible instead of replacing them with new instances...
UPDATE:
My Requirement is to display two Rss files as Tabs on my LWUIT Form
Initially by default first Rss file titles and images should be displayed on first tab
if an end user click on second tab,we should be able to load the second rss file titles and images
I am able to load first Rss File titles,but i am not able to load the second tab if i click on it
How to capture the click event for LWUIT Tab?
Here my code which is not working:
String topNewsurl="TopNews.rss";
String topStoryurl="TopStory.rss";
public class XMLMidlet extends MIDlet{
public void startApp() {
Display.init(this);
Process p;
try {
p = new Process(this);
p.process();
} catch (IOException ex) {
ex.printStackTrace();
}
}
public class Process extends Form {
Process(XMLMidlet midlet) throws IOException {
this.midlet=midlet;
topnews = new Vector();
topstory = new Vector();
tabs = new Tabs();
form1 = new Form();
form2=new Form();
form1.setLayout(new BorderLayout());
form1.setScrollable(false);
image = Image.createImage("/res/Tone.jpg");
Label icon = new Label(image);
form1.setTitleComponent(icon);
form2.setTitleComponent(icon);
form1.setTransitionInAnimator(Transition3D.createRotation(250, true));
try {
newsList = new List(topnews);
newsList.setScrollVisible(false);
newsList.setRenderer(new NewsListCellRenderer());
myNewsList = new List(topstory);
myNewsList.setScrollVisible(false);
myNewsList.setRenderer(new NewsListCellRenderer());
tabs.addTab("Topstory", newsList);
tabs.addTab("TopNews", myNewsList);
tabs.setChangeTabOnFocus(true);
form1.addComponent(BorderLayout.CENTER, tabs);
}
try{
String url = "http:topnews-20.rss";
form1.show();
ParseThread myThread = new ParseThread(this);
myThread.getXMLFeed(url);
} catch (Exception e) {
e.printStackTrace();
}
}
public void addNews(News newsItem) {
//log.debug("addnews");
//System.out.println("addNews");
topnews.addElement(newsItem);
newsList.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
List source = (List) ae.getSource();
News selectedNewsItem = (News) source.getSelectedItem();
if (selectedNewsItem != null) {
displayCompleteNewsScreen(selectedNewsItem);
}
}
});
form1.show();
}
public void keyReleased(int keyCode) {
System.out.println("str");
Component p=this.getFocused();
String str= p.getClass().getName();
if(str.toLowerCase().indexOf("radiobutton")!=-1){
process();
}
From the very vague question it seems you want to capture key presses on a LWUIT Form.
jobsForm.addGameKeyListener(Display.GAME_FIRE,
new ActionListener() {
public void actionPerformed(ActionEvent evt) {
//do something here
}
});
jobsForm.addPointerPressedListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
pointer_click = true;
}
});
jobsForm.addPointerReleasedListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
if (pointer_click) {
//
}
pointer_click = false;
}
});
jobsForm.addPointerDraggedListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
//System.out.println("POINTER DRAGGED");
pointer_click = false;
}
});
I've spent long on this but no success yet. In my application to capture image and send to the server, I get NullPointerException below;
java.lang.NullPointerException: 0
at Files.CameraMIDlet.snap(CameraMIDlet.java:120)
at Files.CameraForm.commandAction(CameraForm.java:116)
at javax.microedition.lcdui.Display$ChameleonTunnel.callScreenListener(), bci=46
at com.sun.midp.chameleon.layers.SoftButtonLayer.processCommand(), bci=74
at com.sun.midp.chameleon.layers.SoftButtonLayer.soft2(), bci=173
at com.sun.midp.chameleon.layers.SoftButtonLayer.keyInput(), bci=78
at com.sun.midp.chameleon.CWindow.keyInput(), bci=38
at javax.microedition.lcdui.Display$DisplayEventConsumerImpl.handleKeyEvent(), bci=17
at com.sun.midp.lcdui.DisplayEventListener.process(), bci=277
at com.sun.midp.events.EventQueue.run(), bci=179
at java.lang.Thread.run(Thread.java:722)
The errors happen at byte[] image = videoControl.getSnapshot("encoding = jpeg"); in the CameraMIDlet and also at midlet.snap(); in the CameraForm, in the code below.
The code for CameraForm is here:
package Files;
import javax.microedition.media.*;
import javax.microedition.lcdui.*;
import javax.microedition.media.control.*;
import java.io.IOException;
class CameraForm extends Form implements CommandListener {
private final CameraMIDlet midlet;
private final Command exitCommand;
private Command captureCommand = null;
private Command showImageCommand = null;
private Player player = null;
private static VideoControl videoControl = null;
private boolean active = false;
private StringItem messageItem;
public CameraForm(CameraMIDlet midlet) {
super("Camera");
this.midlet = midlet;
messageItem = new StringItem("Message", "start");
append(messageItem);
exitCommand = new Command("EXIT", Command.EXIT, 1);
addCommand(exitCommand);
setCommandListener(this);
try {
//creates a new player and set it to realize
player = Manager.createPlayer("capture://video");
player.realize();
//Grap the Video control and set it to the current display
videoControl = (VideoControl) (player.getControl("VideoControl"));
if (videoControl != null) {
append((Item) (videoControl.initDisplayMode(
VideoControl.USE_GUI_PRIMITIVE, null)));
captureCommand = new Command("CAPTURE", Command.SCREEN, 1);
addCommand(captureCommand);
messageItem.setText("OK");
} else {
messageItem.setText("No video control");
}
} catch (IOException ioe) {
messageItem.setText("IOException: " + ioe.getMessage());
} catch (MediaException me) {
messageItem.setText("Media Exception: " + me.getMessage());
} catch (SecurityException se) {
messageItem.setText("Security Exception: " + se.getMessage());
}
}
* the video should be visualized on the sreen
* therefore you have to start the player and set the videoControl visible
synchronized void start() {
if (!active) {
try {
if (player != null) {
player.start();
}
if (videoControl != null) {
videoControl.setVisible(true);
//midlet.snap();
}
} catch (MediaException me) {
messageItem.setText("Media Exception: " + me.getMessage());
} catch (SecurityException se) {
messageItem.setText("Security Exception: " + se.getMessage());
}
active = true;
}
}
* to stop the player. First the videoControl has to be set invisible
* than the player can be stopped
synchronized void stop() {
if (active) {
try {
if (videoControl != null) {
videoControl.setVisible(false);
}
if (player != null) {
player.stop();
}
} catch (MediaException me) {
messageItem.setText("Media Exception: " + me.getMessage());
}
active = false;
}
}
* on the captureCommand a picture is taken and transmited to the server
public void commandAction(Command c, Displayable d) {
if (c == exitCommand) {
midlet.cameraFormExit();
} else {
if (c == captureCommand) {
midlet.snap();
}
}
}
}
The code for CameraMIDlet is below:
package Files;
import java.io.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import javax.microedition.media.control.*;
import java.io.IOException;
import javax.microedition.media.MediaException;
public class CameraMIDlet extends MIDlet {
private CameraForm cameraSave = null;
private DisplayImage displayImage = null;
CameraForm captureThread;
private static VideoControl videoControl;
private StringItem messageItem;
public CameraMIDlet() {
}
/*
* startApp()
* starts the MIDlet and generates cameraSave, displayImage, database
*
**/
public void startApp() {
Displayable current = Display.getDisplay(this).getCurrent();
if (current == null) {
//first call
cameraSave = new CameraForm(this);
displayImage = new DisplayImage(this);
Display.getDisplay(this).setCurrent(cameraSave);
cameraSave.start();
} else {
//returning from pauseApp
if (current == cameraSave) {
cameraSave.start();
}
Display.getDisplay(this).setCurrent(current);
}
}
public void pauseApp() {
if (Display.getDisplay(this).getCurrent() == cameraSave) {
cameraSave.stop();
}
}
public void destroyApp(boolean unconditional) {
if (Display.getDisplay(this).getCurrent() == cameraSave) {
cameraSave.stop();
}
}
private void exitRequested() {
destroyApp(false);
notifyDestroyed();
}
void cameraFormExit() {
exitRequested();
}
/**
* restart the camera again
*
*/
void displayCanvasBack() {
Display.getDisplay(this).setCurrent(cameraSave);
cameraSave.start();
}
/**
* the byte[] of the image should be transmitted to a server
*
**/
void buildHTTPConnection(byte[] byteImage) {
displayImage.setImage(byteImage);
Display.getDisplay(this).setCurrent(displayImage);
HttpConnection hc = null;
OutputStream out = null;
try {
//enode the image data by the Base64 algorithm
String stringImage = Base64.encode(byteImage);
// URL of the Sevlet
String url = new String(
"http://ip-adress:8080/C:/Users/HASENDE/Documents/NetBeansProjects/Mobile/pics");
// Obtain an HTTPConnection
hc = (HttpConnection) Connector.open(url);
// Modifying the headers of the request
hc.setRequestMethod(HttpConnection.POST);
// Obtain the output stream for the HttpConnection
out = hc.openOutputStream();
out.write(stringImage.getBytes());
} catch (IOException ioe) {
StringItem stringItem = new StringItem(null, ioe.toString());
} finally {
try {
if (out != null)
out.close();
if (hc != null)
hc.close();
} catch (IOException ioe) {
}
}
// ** end network
}
/**
* stop the camera, show the captured image and transmit the image to a server
**/
void transmitImage(byte[] image) {
cameraSave.stop();
Display.getDisplay(this).setCurrent(displayImage);
buildHTTPConnection(image);
}
public void snap(){
try {
byte[] image = videoControl.getSnapshot("encoding = jpeg");
transmitImage(image);
messageItem.setText("Ok");
} catch (MediaException me) {
messageItem.setText("Media Exception: " + me.getMessage());
}
}
}
By identifying the statement that throws NPE you get 99% close to finding the bug:
byte[] image = videoControl.getSnapshot("encoding = jpeg");
NPE in above statement means videoControl is null. Now if you look at it closer, you may notice that in CameraMIDlet, videoControl is initialized with null and never changes to anything else - that's why you are getting NPE. By the way, from CameraForm code it looks like you intended to use videoControl object that is defined there, didn't you.
Side note. CameraForm seems to be designed to used in multiple threads (there are synchronized modifiers) - if this is the case, you better make sure that videoControl is also obtained from it in a synchronized way. Also in that case, add volatile modifier in definition of active flag:
private volatile boolean active = false; // in CameraForm
For Capturing photo use canvas instead of Form,
Check follwing code for Photo Capture
public class ImageCaptureCanvas extends Canvas {
UrMidlet midlet;
VideoControl videoControl;
Player player;
SnapShotCanvas snap;
private Display display;
public ImageCaptureCanvas(UrMidlet midlet) throws MediaException {
this.midlet = midlet;
this.display = Display.getDisplay(midlet);
this.setFullScreenMode(true);
try {
player = Manager.createPlayer("capture://image");
player.realize();
videoControl = (VideoControl) player.getControl("VideoControl");
} catch (Exception e) {
dm(e.getClass().getName());
}
videoControl.initDisplayMode(VideoControl.USE_DIRECT_VIDEO, this);
try {
videoControl.setDisplayLocation(0,0);
videoControl.setDisplaySize(getWidth(), getHeight());
} catch (MediaException me) {
try {
videoControl.setDisplayFullScreen(true);
} catch (MediaException me2) {
}
}
dm("icc10");
videoControl.setVisible(true);
dm("icc11");
player.start();
this.display.setCurrent(this);
}
public void dm(String message) {
Form form = new Form("Error");
form.append(message);
display.setCurrent(form);
}
public void paint(Graphics g) {
}
protected void keyPressed(int keyCode) {
boolean prv=false;
int actn=getGameAction(keyCode);
switch (keyCode) {
case KEY_NUM5:
prv=true;
Thread t = new Thread() {
public void run() {
try {
byte[] raw = videoControl.getSnapshot(null);
Image image = Image.createImage(raw, 0, raw.length);
snap = new SnapShotCanvas(image);
display.setCurrent(snap);
} catch (Exception e) {
dm(e.getClass().getName() + " " + e.getMessage());
}
}
};
t.start();
break;
}
if(!prv){
switch (actn) {
case Canvas.FIRE:
Thread t1 = new Thread() {
public void run() {
try {
byte[] raw = videoControl.getSnapshot(null);
Image image = Image.createImage(raw, 0, raw.length);
snap = new SnapShotCanvas(image);
display.setCurrent(snap);
} catch (Exception e) {
dm(e.getClass().getName() + " " + e.getMessage());
}
}
};
t1.start();
break;
}
}
}
}
SnapShotCanvas Code here
class SnapShotCanvas extends Canvas {
private Image image;
public SnapShotCanvas(Image image) {
this.image = image;
setFullScreenMode(true);
}
public void paint(Graphics g) {
g.drawImage(image, getWidth() / 2, getHeight() / 2, Graphics.HCENTER | Graphics.VCENTER);
}
}
How do I create and display an image in j2me application?
And in which folder can I put that image in my application?
This link has exactly what you are looking for to get started.
Basically, to create the image, you call upon Image.createImage();
Image img = Image.createImage("/imageName.png");
If it is in a sub-folder in the Jar:
Image img = Image.createImage("/subDir/imageName.png");
To display the image, you need to paint it to a Canvas through a Graphics instance that is tied to the Canvas (better visualized in the link above).
public void paint(Graphics g) {
...
g.drawImage(img, 0, 0, Graphics.TOP | Graphics.LEFT);
....
}
You could also use the Graphics.drawRegion function, but here is a link to the JavaDocs for J2ME for you to look through to see what is best for your needs.
To draw an Image on a JavaME MIDlet you need a Canvas to paint it on to. You can do as follow:
Firs you have to place the original image file inside your package (usually inside "res" or one of his subdirectories).
Secondly you need to create a class extending Canvas and implement the paint method:
import java.io.IOException;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
public class MyCanvas extends Canvas {
private Image image;
public MyCanvas(){
try {
image = Image.createImage("picture.png");
} catch (IOException e) {
e.printStackTrace();
}
}
protected void paint(Graphics g) {
g.drawImage(image, 10, 10, Graphics.TOP | Graphics.LEFT);
}
}
Now you need to create an instance of this class and tell the MIDlet di display it, for example:
import javax.microedition.lcdui.Display;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;
public class MyMIDlet extends MIDlet {
public MyMIDlet(){
}
protected void destroyApp(boolean unconditional)
throws MIDletStateChangeException {
}
protected void pauseApp() {
}
protected void startApp() throws MIDletStateChangeException {
Display.getDisplay(this).setCurrent(new MyCanvas());
}
}
Remember that this way the Canvas will be painted only one time and if you change something, you need to call the repaint() method.
This source code builds on previously posted comments:
import java.io.*;
import javax.microedition.io.*;
import javax.microedition.io.file.FileConnection;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
public class ImageLoader extends MIDlet
implements CommandListener, Runnable {
private Display mDisplay;
private Form mForm;
public ImageLoader() {
mForm = new Form("Connecting...");
mForm.addCommand(new Command("Exit", Command.EXIT, 0));
mForm.setCommandListener(this);
}
public void startApp() {
if (mDisplay == null) mDisplay = Display.getDisplay(this);
mDisplay.setCurrent(mForm);
Thread t = new Thread(this);
t.start();
}
public void pauseApp() {}
public void destroyApp(boolean unconditional) {}
public void commandAction(Command c, Displayable s) {
if (c.getCommandType() == Command.EXIT)
notifyDestroyed();
}
public void run() {
FileConnection fc = null;
DataInputStream in = null;
DataOutputStream out = null;
try {
fc = (FileConnection)Connector.open("file:///root1/i.PNG");
int length = (int)fc.fileSize();//possible loss of precision may throw error
byte[] data = null;
if (length != -1) {
data = new byte[length];
in = new DataInputStream(fc.openInputStream());
in.readFully(data);
}
else {
int chunkSize = 512;
int index = 0;
int readLength = 0;
in = new DataInputStream(fc.openInputStream());
data = new byte[chunkSize];
do {
if (data.length < index + chunkSize) {
byte[] newData = new byte[index + chunkSize];
System.arraycopy(data, 0, newData, 0, data.length);
data = newData;
}
readLength = in.read(data, index, chunkSize);
index += readLength;
} while (readLength == chunkSize);
length = index;
}
Image image = Image.createImage(data, 0, length);
ImageItem imageItem = new ImageItem(null, image, 0, null);
mForm.append(imageItem);
mForm.setTitle("Done.");
fc = (FileConnection)Connector.open("file:///root1/x.PNG");
if(!fc.exists()){
try{
fc.create();
}catch(Exception ce){System.out.print("Create Error: " + ce);}
}
out = new DataOutputStream(fc.openOutputStream());
out.write(data);
}
catch (IOException ioe) {
StringItem stringItem = new StringItem(null, ioe.toString());
mForm.append(stringItem);
mForm.setTitle("Done.");
}
finally {
try {
if (in != null) in.close();
if (fc != null) fc.close();
}
catch (IOException ioe) {}
}
}
}
The code is modified from the link Fostah provided here.
It opens an image, displays it, then saves it as x.PNG instead of i.PNG using FileConnection. The tricky thing to watch for is where the file is being saved/loaded from. If your using J2meWTK with Netbeans, then the folder will be displayed in the output window when you run the mobile app. The folder will be something like temp.DefaultColorPhone/filesystem/root1 . That is where you will have to have an image. I'm not sure how to have the temp environment created with the image by default. That means you have to start the mobile app, check where the temp root1/ is located, in your IDE, then drop the image into the folder, then proceed with running the ImageLoader application. I'll try to find out how to automate this by posting a question. Also, Start with a small image, 50x50 (bigger images may cause problems).