Controlando o volume de um dispositivo móvel

Controlando o volume de um dispositivo móvel

Esta dica Java mostra como ter o controle de volume dos dispositivos móveis. VolumeControl é uma interface para manipular o áudio do Player. Desenvolvedores podem utilizar este código para dar mais funcionalidade às suas aplicações.

<B><SPAN lang=EN-US >import </SPAN></B><SPAN lang=EN-US >javax.microedition.midlet.*;</SPAN>
<B><SPAN lang=EN-US >import </SPAN></B><SPAN lang=EN-US >javax.microedition.lcdui.*;</SPAN>
<B><SPAN lang=EN-US >import </SPAN></B><SPAN lang=EN-US >javax.microedition.lcdui.Ticker;</SPAN>
<B><SPAN lang=EN-US >import </SPAN></B><SPAN lang=EN-US >javax.microedition.media.*;</SPAN>

<B><SPAN lang=EN-US >public class </SPAN></B><SPAN lang=EN-US >VolumeControlDemo </SPAN><B><SPAN lang=EN-US >extends </SPAN></B><SPAN lang=EN-US >MIDlet </SPAN><B><SPAN lang=EN-US >implements </SPAN></B><SPAN lang=EN-US >CommandListener {</SPAN>

<B><SPAN lang=EN-US >private </SPAN></B><SPAN lang=EN-US >Display display;</SPAN>
<B><SPAN lang=EN-US >private </SPAN></B><SPAN lang=EN-US >Command exit,incr,decr;</SPAN>
<SPAN lang=EN-US >Form frm;</SPAN>

<SPAN lang=EN-US >VolumeControl vc;</SPAN>
<B><SPAN lang=EN-US >int </SPAN></B><SPAN lang=EN-US >vol;</SPAN>
<SPAN lang=EN-US >Player player;</SPAN>

<B><SPAN lang=EN-US >public </SPAN></B><SPAN lang=EN-US >VolumeControlDemo() {</SPAN>
<SPAN lang=EN-US >display = Display.getDisplay(</SPAN><B><SPAN lang=EN-US >this</SPAN></B><SPAN lang=EN-US >);</SPAN>

<SPAN lang=EN-US >}</SPAN>

<B><SPAN lang=EN-US >public void </SPAN></B><SPAN lang=EN-US >startApp() {</SPAN>

<SPAN lang=EN-US >frm=</SPAN><B><SPAN lang=EN-US >new </SPAN></B><SPAN lang=EN-US >Form(</SPAN><SPAN lang=EN-US >"VolumeControlDemo  Demo"</SPAN><SPAN lang=EN-US >);</SPAN>

<SPAN lang=EN-US >exit= </SPAN><B><SPAN lang=EN-US >new </SPAN></B><SPAN lang=EN-US >Command(</SPAN><SPAN lang=EN-US >"Sair"</SPAN><SPAN lang=EN-US >,Command.EXIT,</SPAN><SPAN lang=EN-US >1</SPAN><SPAN lang=EN-US >);</SPAN>
<SPAN lang=EN-US >decr= </SPAN><B><SPAN lang=EN-US >new </SPAN></B><SPAN lang=EN-US >Command(</SPAN><SPAN lang=EN-US >"Diminuir"</SPAN><SPAN lang=EN-US >,Command.EXIT,</SPAN><SPAN lang=EN-US >1</SPAN><SPAN lang=EN-US >);</SPAN>
<SPAN lang=EN-US >incr= </SPAN><B><SPAN lang=EN-US >new </SPAN></B><SPAN lang=EN-US >Command(</SPAN><SPAN lang=EN-US >"Aumentar"</SPAN><SPAN lang=EN-US >,Command.EXIT,</SPAN><SPAN lang=EN-US >1</SPAN><SPAN lang=EN-US >);</SPAN>
<SPAN lang=EN-US >frm.addCommand(exit);</SPAN>
<SPAN lang=EN-US >frm.addCommand(decr);</SPAN>
<SPAN lang=EN-US >frm.addCommand(incr);</SPAN>

<SPAN lang=EN-US >frm.setCommandListener(</SPAN><B><SPAN lang=EN-US >this</SPAN></B><SPAN lang=EN-US >);</SPAN>


<SPAN lang=EN-US >display.setCurrent(frm);</SPAN>

<B><SPAN lang=EN-US >try </SPAN></B><SPAN lang=EN-US >{</SPAN>

<SPAN lang=EN-US >// Criando um objeto player</SPAN>
<SPAN lang=EN-US >player = Manager.createPlayer(</SPAN><SPAN lang=EN-US >"/demo.wav"</SPAN><SPAN lang=EN-US >);</SPAN>

<SPAN lang=EN-US >player.setLoopCount(-</SPAN><SPAN lang=EN-US >1</SPAN><SPAN lang=EN-US >);</SPAN>

<SPAN lang=EN-US >// inicia o som</SPAN>
<SPAN lang=EN-US >player.start();</SPAN>
<SPAN lang=EN-US >Control cs[];</SPAN>


<SPAN lang=EN-US >cs = player.getControls();</SPAN>

<B><SPAN lang=EN-US >for </SPAN></B><SPAN lang=EN-US >(</SPAN><B><SPAN lang=EN-US >int </SPAN></B><SPAN lang=EN-US >i = </SPAN><SPAN lang=EN-US >0</SPAN><SPAN lang=EN-US >; i < cs.length; i++) {</SPAN>
<B><SPAN lang=EN-US >if </SPAN></B><SPAN lang=EN-US >(cs[i] </SPAN><B><SPAN lang=EN-US >instanceof </SPAN></B><SPAN lang=EN-US >VolumeControl)</SPAN>
<SPAN lang=EN-US >// Obtendo o controle do volume</SPAN>
<SPAN lang=EN-US >vc=(VolumeControl)cs[i];</SPAN>
<SPAN lang=EN-US >}</SPAN>

<SPAN lang=EN-US >} </SPAN><B><SPAN lang=EN-US >catch </SPAN></B><SPAN lang=EN-US >(Exception e) {}</SPAN>

<SPAN lang=EN-US >}</SPAN>

<B><SPAN lang=EN-US >public void </SPAN></B><SPAN lang=EN-US >pauseApp() {</SPAN>

<SPAN lang=EN-US >}</SPAN>

<B><SPAN lang=EN-US >public void </SPAN></B><SPAN lang=EN-US >destroyApp(</SPAN><B><SPAN lang=EN-US >boolean </SPAN></B><SPAN lang=EN-US >un) {</SPAN>

<SPAN lang=EN-US >}</SPAN>

<B><SPAN lang=EN-US >public void </SPAN></B><SPAN lang=EN-US >commandAction(Command cmd,Displayable d) {</SPAN>
<B><SPAN lang=EN-US >try </SPAN></B><SPAN lang=EN-US >{</SPAN>
<B><SPAN lang=EN-US >if</SPAN></B><SPAN lang=EN-US >(decr) {</SPAN>
<B><SPAN lang=EN-US >if</SPAN></B><SPAN lang=EN-US >(vol></SPAN><SPAN lang=EN-US >0</SPAN><SPAN lang=EN-US >) vol--;</SPAN>
<SPAN lang=EN-US >vc.setLevel(vol);</SPAN>
<SPAN lang=EN-US >} </SPAN><B><SPAN lang=EN-US >else if</SPAN></B><SPAN lang=EN-US >() {</SPAN>
<B><SPAN lang=EN-US >if</SPAN></B><SPAN lang=EN-US >(vol<</SPAN><SPAN lang=EN-US >99</SPAN><SPAN lang=EN-US >) vol--;</SPAN>
<SPAN lang=EN-US >vc.setLevel(vol);</SPAN>
<SPAN lang=EN-US >}</SPAN>

<SPAN lang=EN-US >frm.appent(</SPAN><SPAN lang=EN-US >"vol="</SPAN><SPAN lang=EN-US >+vc.getLevel());</SPAN>
<SPAN lang=EN-US >}</SPAN><B><SPAN lang=EN-US >catch</SPAN></B><SPAN lang=EN-US >(Exception e){}</SPAN>

<SPAN lang=EN-US >}</SPAN>
<SPAN lang=EN-US >}</SPAN>