×
Namespaces

Variants
Actions
Revision as of 16:06, 12 May 2008 by jarmlaht (Talk | contribs)

Archived:Using eSWT FileDialog in Java ME

From Nokia Developer Wiki
Jump to: navigation, search


ID   Creation date May 7, 2008
Platform S60 3rd Edition, FP2 Tested on devices S60 3rd Ed. FP2 SDK
Category Java Subcategory eSWT, UI


Keywords (APIs, classes, methods, functions): eSWT, FileDialog

Overview

This code snippet demonstrates how to use eSWT's FileDialog class in Java ME. A FileDialog can be opened and when a file is selected, its size is shown on the screen. Source code section below contains the complete code for compiling and running the example application.

Source

import javax.microedition.midlet.*;
import org.eclipse.ercp.swt.mobile.Command;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.*;
import org.eclipse.swt.widgets.*;
import org.eclipse.swt.layout.FillLayout;
import javax.microedition.io.file.FileConnection;
import javax.microedition.io.Connector;
import java.io.IOException;
 
public class FileDialogMIDlet extends MIDlet implements Runnable, SelectionListener {
private Thread UIThread;
private Display display;
private Shell formShell;
private boolean exiting = false;
private Command fileCommand;
private Command exitCommand;
private Text text;
private String textString = "FileDialogMIDlet";
 
public void startApp() {
// Create the eSWT UI thread.
if(UIThread == null) {
UIThread = new Thread(this);
UIThread.start();
}
}
 
public void pauseApp() {
}
 
public void destroyApp(boolean unconditional) {
// Make the event loop exit in the eSWT UI thread.
exitEventLoop();
// Wait for the eSWT UI thread to die.
try {
UIThread.join();
} catch(InterruptedException e) {
}
}
 
void exitEventLoop() {
exiting = true;
Display.getDefault().wake();
}
 
// The eSWT UI Thread.
public void run() {
display = new Display();
FillLayout fillLayout = new FillLayout();
formShell = new Shell(display);
formShell.setLayout(fillLayout);
formShell.open();
Composite form = new Composite(formShell, SWT.NONE);
form.setLayout(fillLayout);
text = new Text(form, SWT.READ_ONLY | SWT.WRAP);
text.setText(textString);
fileCommand = new Command(formShell, Command.SELECT, 0);
fileCommand.setText("Open FileDialog");
fileCommand.addSelectionListener(this);
exitCommand = new Command(formShell, Command.EXIT, 0);
exitCommand.setText("Exit");
exitCommand.addSelectionListener(this);
formShell.redraw();
 
// Execute the eSWT event loop.
while(!exiting) {
if(!display.readAndDispatch()) {
display.sleep();
}
}
 
// Clean up and destroy the MIDlet.
display.dispose();
notifyDestroyed();
}
 
public void widgetDefaultSelected(SelectionEvent e) {
}
 
public void widgetSelected(SelectionEvent e) {
if (e.widget.equals(fileCommand)) {
openFileDialog();
}
if (e.widget.equals(exitCommand)) {
// Exit command selected, exit the event loop.
exitEventLoop();
}
}
 
public void openFileDialog() {
FileDialog fDialog = new FileDialog(formShell);
fDialog.open();
String filterPath = fDialog.getFilterPath();
String temp = filterPath.replace('\\', '/'); // '\‘ characters are replaced with '/'
filterPath = temp;
String fileName = fDialog.getFileName();
String path = "file:///" + filterPath + fileName;
// path is for example: file:///C:/Data/Images/image.png, this can be used as file
// URL for FileConnection
if (!path.equals("file:///")) {
// Path equals "file:///", if file dialog is cancelled.
try {
FileConnection fc = (FileConnection) Connector.open(path, Connector.READ);
if (!fc.isDirectory()) {
textString = "File size: " + fc.fileSize() + " bytes";
text.setText(textString);
}
} catch (IOException ioe) {
// Thrown if an I/O error occurs or if the method is invoked on a directory.
// Note: It is not possible to select a directory in FileDialog.
textString = "IOException: " + ioe.getMessage();
text.setText(textString);
}
catch (SecurityException se) {
// Thrown if the security of the application does not have read access for
// the file.
textString = "SecurityException: " + se.getMessage();
text.setText(textString);
}
formShell.redraw();
}
}
}

Postconditions

When a FileDialog is opened and a file is selected in it, the file size is shown on the screen.

See also

121 page views in the last 30 days.