www.pudn.com > audiodemo.rar > MixCanvas.java
/*
* @(#)MixCanvas.java 1.10 02/08/15 @(#)
*
* Copyright (c) 2001-2002 Sun Microsystems, Inc. All rights reserved.
* PROPRIETARY/CONFIDENTIAL
* Use is subject to license terms.
*/
package example.audiodemo;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.media.*;
import javax.microedition.media.control.*;
import java.io.*;
public class MixCanvas extends Canvas implements CommandListener, Runnable {
private static final String TITLE_TEXT = "audio player";
private static final int[] notes = {69, 70,71,72,73,74, 75, 76};
static Player wavPlayer = null, tonePlayer = null;
static Image logo = null;
private int idx = 0, ip =0;
Display parentDisplay;
private Command backCommand = new Command("Back", Command.BACK,
1);
private Command playCommand = new Command("Play",
Command.ITEM, 1);
private Command pauseCommand = new Command("Pause",
Command.ITEM, 1);
private Command toneCommand = new Command("Tone",
Command.ITEM, 1);
private Alert alert;
//In case the user ended the player using the back command
//or the 'End' button (the red one), if the WavPlayer did not
//start yet there is a possibility that it will start after a while.
//stopSound is here to catch this case and avoid playing the sound.
private boolean stopSound = false;
public MixCanvas(Display parentDisplay) {
super();
this.idx = 0;
this.parentDisplay = parentDisplay;
initialize();
}
void initialize() {
addCommand(backCommand);
setCommandListener(this);
try {
logo = Image.createImage("/icons/logo.png");
} catch (Exception ex) {
logo = null;
}
if ( logo == null) {
System.out.println("can not load logo.png");
}
alert = new Alert("Warning", "Can not create player", null, null);
alert.setTimeout(1000);
}
/*
* Respond to commands, including back
*/
public void commandAction(Command c, Displayable s) {
if (s == this) {
if (c == backCommand) {
stopSound();
parentDisplay.setCurrent(MixTest.getList());
} else if ( c == toneCommand ) {
try {
Manager.playTone(notes[ip], 1000, 100);
ip++;
if ( ip >= 8 )
ip = 0;
} catch (Exception ex) {
System.out.println("get an exception for tone");
}
} else if (c == playCommand) {
playSound();
} else if (c == pauseCommand) {
pauseSound();
}
}
}
public void setIndex(int idx) {
this.idx = idx;
}
private void createWavPlayer() {
// method createWavPlayer() runs on GUI thread. Manager.createPlayer()
// will potentially invoke a blocking I/O. This is not the good
// practice recommonded by MIDP programming style. So here we
// will create the Player in a separate thread.
new Thread(this).start();
}
public void run() {
try {
if (wavPlayer == null) {
wavPlayer = Manager.createPlayer(MixTest.wavUrl);
wavPlayer.setLoopCount(-1);
}
if(stopSound) {
return;
}
wavPlayer.start();
} catch (Exception ex) {
// ex.printStackTrace();
if (wavPlayer != null) {
wavPlayer.close();
wavPlayer = null;
}
parentDisplay.setCurrent(alert);
}
}
private void createTonePlayer() {
byte d = 8;
byte C4 = ToneControl.C4;
byte D4 = ToneControl.C4 + 2; // a whole step
byte E4 = ToneControl.C4 + 4; // a major third
byte G4 = ToneControl.C4 + 7; // a fifth
byte rest = ToneControl.SILENCE; // eighth-note rest
byte[] mySequence = new byte[] {
ToneControl.VERSION, 1,
ToneControl.TEMPO, 30,
ToneControl.BLOCK_START, 0,
E4,d,D4,d,C4,d,D4,d,E4,d,E4,d,E4,d,rest,d,
ToneControl.BLOCK_END,0,
ToneControl.PLAY_BLOCK,0,
D4,d,D4,d,D4,d,rest,d,E4,d,G4,d,G4,d,rest,d,//play "B" section
ToneControl.PLAY_BLOCK,0, // content of "A" section
D4,d,D4,d,E4,d,D4,d,C4,d,rest,d// play "C" section
};
try {
if ( tonePlayer == null) {
tonePlayer = Manager.createPlayer(Manager.TONE_DEVICE_LOCATOR);
tonePlayer.setLoopCount(-1);
tonePlayer.realize();
ToneControl tc = (ToneControl)tonePlayer.getControl("javax.microedition.media.control.ToneControl");
tc.setSequence(mySequence);
}
if ( tonePlayer != null && !stopSound) {
tonePlayer.start();
}
} catch (Exception ex) {
// ex.printStackTrace();
if (tonePlayer != null) {
tonePlayer.close();
tonePlayer = null;
}
parentDisplay.setCurrent(alert);
}
}
public void playSound() {
stopSound = false;
switch(idx) {
case 0: // wave + tone
addCommand(toneCommand);
createWavPlayer();
break;
case 1: // toneseq + tone
addCommand(toneCommand);
createTonePlayer();
break;
case 2:
removeCommand(playCommand);
addCommand(pauseCommand);
createWavPlayer();
createTonePlayer();
break;
}
}
public void stopSound() {
stopSound = true;
if (tonePlayer != null) {
tonePlayer.close();
tonePlayer = null;
}
if (wavPlayer != null) {
wavPlayer.close();
wavPlayer = null;
}
switch(idx) {
case 0:
case 1:
removeCommand(toneCommand);
break;
case 2:
removeCommand(pauseCommand);
removeCommand(playCommand);
break;
}
}
public void pauseSound() {
removeCommand(pauseCommand);
addCommand(playCommand);
try {
if ( wavPlayer != null)
wavPlayer.stop();
if ( tonePlayer != null )
tonePlayer.stop();
} catch (MediaException e) {
// Nothing much to do here.
}
}
public void paint(Graphics g) {
int w = getWidth();
int h = getHeight();
String cname = "";
switch(idx) {
case 0:
cname = "test-wav.wav";
break;
case 1:
cname = "tone seq";
break;
case 2:
cname = "wave+toneseq";
break;
}
g.setColor(0);
g.fillRect(0, 0, w, h);
if ( logo != null ) {
g.drawImage(logo, w/2, 30, Graphics.TOP | Graphics.HCENTER);
}
g.setColor(0xFF7f00);
g.drawString("audio Player", w/2, 8, Graphics.TOP | Graphics.HCENTER);
//g.drawString("audio player!", w/2, 64, Graphics.TOP | Graphics.HCENTER);
g.drawString(cname, 0, 84, Graphics.TOP | Graphics.LEFT);
}
protected void keyPressed(int keycode) {
switch (keycode) {
case KEY_STAR:
changeVolume(-10);
break;
case KEY_POUND:
changeVolume(10);
break;
}
}
private void changeVolume(int diff) {
VolumeControl vc;
if ( wavPlayer != null) {
vc = (VolumeControl) wavPlayer.getControl("VolumeControl");
if (vc != null) {
int cv = vc.getLevel();
cv += diff;
cv = vc.setLevel(cv);
}
}
if ( tonePlayer != null) {
vc = (VolumeControl) tonePlayer.getControl("VolumeControl");
if (vc != null) {
int cv = vc.getLevel();
cv += diff;
cv = vc.setLevel(cv);
}
}
}
}