Tag: Linux

I planed make an self-desgin photo or movie player base on Raspberry. Also I can use it as photo frame. If I need improve the performance of the PI, I need write it with Python, I think.

Part 1 – Build the Foundation

In this part, we will focus on preparing Raspbian Lite.

1. Download the latest Raspbian Lite image.
2. Format the SD / microSD card with Raspbian Lite (Plenty of guides out there on how to do this. For macOS, Linux, and Windows users, Etcher is an easy to use application that can help you do this.)
3. Insert the SD / microSD card into the Pi.
4. Connect the Pi to the Internet using an Ethernet cable. If you want to use Wi-Fi instead, you will have to read on how to configure your wireless receiver using the command line after your Pi has finished booting.
5. Connect your TV / Monitor and keyboard. (Mouse is optional at this time.) Turn on the Pi. The Pi should boot up successfully and a prompt to log in will appear.
6. Log into Raspbian. The username is pi and the password is raspberry.

7. We will install Xorg. To do this type in:

sudo apt-get install –no-install-recommends xserver-xorg

sudo apt-get install –no-install-recommends xinit

now, you can write you java program now. For example, I wrote a test program with a button in the center of screen. once I click the button, the window will change to the full size of the screen.

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;

public class FullScreenTest {
public static void main(String[] args) {
final JFrame f = new JFrame(“FullScreenTest”);
final JButton btn = new JButton(“FullScreen”);
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (btn.getText().equals(“FullScreen”)) {
f.dispose();
f.setUndecorated(true);
f.getGraphicsConfiguration().getDevice().setFullScreenWindow(f);
f.setVisible(true);
btn.setText(“NormalMode”);
} else {
f.dispose();
f.setUndecorated(false);
f.getGraphicsConfiguration().getDevice().setFullScreenWindow(null);
f.setVisible(true);
btn.setText(“FullScreen”);
}
}
});

f.getContentPane().setLayout(new FlowLayout());
f.getContentPane().add(btn);
f.pack();
f.setLocationRelativeTo(null);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
}

Pack the file into a jar file like GUI.jar.

In order to have a command or program run when the Pi boots, you can add commands to the rc.local file. This is especially useful if you want to be able to plug your Pi in to power headless, and have it run a program without configuration or a manual start.

EDITING RC.LOCAL

On your Pi, edit the file /etc/rc.local using the editor of your choice. You must edit with root, for example:

sudo nano /etc/rc.local

Add commands below the comment, but leave the line exit 0 at the end, then save the file and exit.

sudo xinit /usr/local/jdk1.8.0_77/bin/java -jar /usr/local/mypi/GUI.jar — :1 &

Reboot your PI, then done!