I am trying to make a BeatBox by using Java, but my code is not running and it shows problem in following line:
background.setBorder(BorderFactory.createEmptyBorder(10,10,10,10));
Please assist me in finding a solution as how to fix up the problem.
import java.awt.*;
import javax.swing.*;
import javax.sound.midi.*;
import java.util.*;
import java.awt.event.*;
public class BeatBox {
JPanel mainPanel;
ArrayList<JCheckBox> checkboxList;
Sequencer sequencer;
Sequence sequence;
Track track;
JFrame theFrame;
String[] instrumentNames={ "Bass Drum","Closed Hi-Hat","Open Hi Hat","Acoustic Snare","Crash Cymbol","Hand Clap","High Tom","Hi Bongo","Maracas","Whistle","Low Conga","Cowbell","Vivraslap","Low-mid Tom","High Agogo", "Open Hi Conga"};
int[] instruments={35,42,46,38,49,50,60,70,72,64,56,58,47,67,63};
public static void main(String[] args){
new BeatBox().buildGUI();
}
public void buildGUI(){
theFrame=new JFrame ("Cyber BeatBox");
theFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
BorderLayout layout =new BorderLayout();
background.setBorder(BorderFactory.createEmptyBorder(10,10,10,10));//problem
checkboxList=new ArrayList<JCheckBox>();
Box buttonBox=new Box(BoxLayout.Y_AXIS);
JButton start=new JButton("Start");
start.addActionListener(new MyStartListener());;
buttonBox.add(start);
JButton stop=new JButton("Stop");
stop.addActionListener(new MyStopListener());;
buttonBox.add(stop);
JButton upTempo=new JButton("Tempo Up");
start.addActionListener(new MyUpTempoListener());;
buttonBox.add(upTempo);
JButton downTempo=new JButton("Tempo Down");
start.addActionListener(new MyDownTempoListener());
buttonBox.add(downTempo);
Box nameBox=new Box(BoxLayout.Y_AXIS);
for (int i=0;i<16;i++){
nameBox.add(new Label(instrumentNames[i]));
}
background.add(BorderLayout.EAST,buttonBox);//problem
background.add(BorderLayout.WEST,nameBox);//problem
theFrame.getContentPane().add(background);//problem
GridLayout grid=new GridLayout(16,16);
grid.setVgap(1);
grid.setHgap(2);
mainPanel.add(BorderLayout.CENTER,mainPanel);
for (int i=0;i<256;i++){
JCheckBox c=new JCheckBox();
c.setSelected(false);
checkboxList.add(c);
mainPanel.add(c);
}
setUpMidi();
theFrame.setBounds(50,50,300,300);
theFrame.pack();
theFrame.setVisible(true);
}
public void setUpMidi(){
try{
sequencer=MidiSystem.getSequencer();
sequencer.open();
sequence=new Sequence(Sequence.PPQ,4);
track=sequence.createTrack();sequencer.setTempoInBPM(120);
}catch(Exception e){e.printStackTrace();}
}
public void buildTrackAndStart(){
int[] trackList=null;
sequence.deleteTrack(track);
track=sequence.createTrack();
for(int i=0;i<16;i++){
trackList=new int[16];
int key=instruments[i];
for(int j=0;j<16;j++){
JCheckBox jc=(JCheckBox) checkboxList.get(j+(16*i));
if(jc.isSelected()){
trackList[j]=key;
}else {
trackList[j]=0;
}
}
makeTracks(trackList);
track.add(makeEvent(176,1,127,0,16));
}
track.add(makeEvent(192,9,1,0,15));
try{
sequencer.setSequence(sequence);
sequencer.setLoopCount(sequencer.LOOP_CONTINUOUSLY);
sequencer.start();
sequencer.setTempoInBPM(120);
}catch(Exception e){e.printStackTrace();}
}
public class MyStartListener implements ActionListener{
public void actionPerformed(ActionEvent a){
buildTrackAndStart();
}
}
public class MyStopListener implements ActionListener{
public void actionPerformed(ActionEvent a){
sequencer.stop();
}
}
public class MyUpTempoListener implements ActionListener{
public void actionPerformed(ActionEvent a){
float tempoFactor=sequencer.getTempoFactor();
sequencer.setTempoFactor((float)(tempoFactor*1.03));
}
}
public class MyDownTempoListener implements ActionListener{
public void actionPerformed(ActionEvent a){
float tempoFactor=sequencer.getTempoFactor();
sequencer.setTempoFactor((float)(tempoFactor*.97));
}
}
public void makeTracks(int[] list){
for(int i=0;i<16;i++){
int key=list[i];
if(key!=0){
track.add(makeEvent(144,9,key,100,i));
track.add(makeEvent(128,9,key,100,i+1));
}
}
}
public MidiEvent makeEvent(int comd,int chan,int one,int two,int tick){
MidiEvent event=null;
try{
ShortMessage a=new ShortMessage();
a.setMessage(comd,chan,one,two);
event=new MidiEvent(a,tick);
}catch(Exception e){e.printStackTrace();}
return event;
}
}
I don't know from where you get this code. If you have written this by yourself, then my suggestion is start reading basics of Java and Swing now. This code has a lot of problems, I have modified some, now it has no compilation error. But please don't follow this kind of codes.
The modified code with no compilation error: