In the Emulator window, click the button underneath "Launch."
The
emulator displays a Splash Screen component then File Browser, as shown:
Contributed by Karol Harezlak
The Visual Mobile Designer (VMD) is a graphical interface within NetBeans Mobility that enables you to design mobile applications using drag and drop components. The VMD allows you to define the application flow and design your GUI using the components supplied by the IDE or components you design yourself. The VMD contains many standard User Interface (UI) components that you can use to create applications such as Lists, Alerts, Forms and Images. It also includes custom components that simplify the creation of more complex features, such as Wait Screens, Splash Screens, Table Items and more.
File browser is a custom component that provides a user interface to work with device file system. It provides basic functionality to browse content of devices storage memory. This component utilizes The FileConnection API which is part of the JSR-75 specification for PDA Optional Packages for the Java ME Platform. JSR-75 is not a part of the MIDP 2.0 specification which is why this custom component can be used only with JSR-75 enabled devices.
This example shows you how to use the File Browser component in a mobile application for JSR-75 enabled devices. You'll learn the basic features of the the components, and how to browse content of device memory storage and display content of chosen text files.
Besides the File Browser custom component we'll use two other MIDP components: Splash Screen and TextBox.
Before you begin, you need to install the following software on your computer:
If you are new to NetBeans Mobility, you should start with the NetBeans Mobility MIDP Quick Start Guide before continuing.
Before we begin, you might want to see final result of the tutorial.
Take the following steps to install the FileBrowserExample application:
In the Emulator window, click the button underneath "Launch."
The
emulator displays a Splash Screen component then File Browser, as shown:
Now that you have seen the File Browser component in action, let's go back to the beginning and create this application. To create the application, do the following:
FileBrowserExample in the Project Name field. Change
the Project Location to a directory on your system. From now on, let's refer
to this directory as $PROJECTHOME.
Click Finish.
The project folder contains all of your sources and
project metadata, such as the project Ant script. The application itself is
displayed in the Flow Design window of the Visual Mobile Designer.
FileBrowserExample project in the Project Window,
then choose File New File (Ctrl-N) . Under Categories, select Java Classes.
Under File Types, select Java Package. Click Next.
filebrowserexample in the Package Name field. Click
Finish.
filebrowserexample package in the Project window,
then choose File New File (Ctrl-N) . Under Categories, select MIDP. Under File
Types, select Visual MIDlet. Click Next.
Enter FileBrowserExample into MIDlet Name and MIDP Class Name
fields. Click Finish.
Click on slashScreen and, in the Properties Window, change value of property Text from "null" to the "File Browser Example"
Choose the Back Command from the Commands section of the Component Palette and drag and drop it into the textBox component.
In the Flow design window, click on the Start Point on the Mobile Device
and drag it to the spalshScreen component. In the same manner, connect the
components together as shown in the following graphic.
Insert the following code at the end of the source code. This method is responsible for reading the selected files:
/**
* Read file
*/
private void readFile() {
try {
FileConnection textFile = fileBrowser.getSelectedFile();
getTextBox().setString("");
InputStream fis = textFile.openInputStream();
byte[] b = new byte[1024];
int length = fis.read(b, 0, 1024);
fis.close();
if (length > 0) {
textBox.setString(new String(b, 0, length));
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
Find commandAction method in the source code:
Insert
readFile(); into pre-action section of the
FileBrowser.SELECT_FILE_COMMAND (right after: if (command
== FileBrowser.SELECT_FILE_COMMAND), where it says //insert
pre-action code here):
To add additional files to the WTK storage memory read the Sun Java Wireless Toolkit for CLDC User's Guide (section: 4.3.2.1 Persistent Storage) Using the Emulator Added files and folders are be visible using our File Browser application.
Press <F6> to Run the main project or select Run > Run Main Project.
The NetBeans IDE provides API Javadocs for the File Browser component, as well as other components you can use in the VMD. To read the Javadocs for the File Browser component:
Click org.netbeans.microedition.lcdui.pda to see links for the
component information.