Package COM. example. test2; import android. media. audiomanager; import android. media. mediaplayer; import android. OS. bundle; import android. app. activity; import android. app. service; import android. view. menu; import android. view. view; import android. widget. button; import android. widget. compoundbutton; import android. widget. compoundbutton. oncheckedchangelistener; import android. widget. togglebutton; public class Mai Nactivity extends activity {private button btnplay = NULL, btnupper = NULL, btnlower = NULL; private togglebutton tbmute = NULL; private mediaplayer = NULL; // audio frequency private audiomanager = NULL; // audio @ override public void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); setcontentview (R. layout. activity_main); audiomanager = (audiomanager) getsystemservice (service. au Dio_service); btnplay = (button) findviewbyid (R. id. btnplay); btnupper = (button) findviewbyid (R. id. btnupper); btnlower = (button) findviewbyid (R. id. btnlower); btnplay. setonclicklistener (listener); btnupper. setonclicklistener (listener); btnlower. setonclicklistener (listener); tbmute = (togglebutton) findviewbyid (R. id. tbmute); tbmute. setoncheckedchangelistener (New oncheckedchangelistener () {public void onchecked Changed (compoundbutton buttonview, Boolean ischecked) {audiomanager. setstreammute (audiomanager. stream_music ,! Ischecked); // set whether to mute});} view. onclicklistener listener = new view. onclicklistener () {public void onclick (view v) {@ suppresswarnings ("UNUSED") button BTN = (button) V; Switch (v. GETID () {case R. id. btnplay: // play music mediaplayer = mediaplayer. create (mainactivity. this, R. raw. music); mediaplayer. setlooping (true); // sets mediaplayer for loop playback. start (); // playback sound break; case R. id. btnupper: // increase the volume // adjuststreamvolume: adjust the volume of the specified audio type audiomanager. adjuststreamvolume (audiomanager. stream_music, audiomanager. adjust_raise, audiomanager. flag_show_ui); // raise the voice break; case R. id. btnlower: // reduce the volume // first parameter: Sound type // second parameter: adjust the volume direction // third parameter: Optional flag audiomanager. adjuststreamvolume (audiomanager. stream_music, audiomanager. adjust_lower, audiomanager. flag_show_ui); // lowering the voice break ;}}};}
<? XML version = "1.0" encoding = "UTF-8"?> <Linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android" Android: Orientation = "vertical" Android: layout_width = "fill_parent" Android: layout_height = "fill_parent"> <button Android: id = "@ + ID/btnplay" Android: layout_width = "fill_parent" Android: layout_height = "wrap_content" Android: text = "Play Music"/> <linearlayout Android: orientation = "horizontal" Android: layout_width = "wrap_content" Android: layout_height = "wrap_content" Android: layout_gravity = "center_horizontal"> <togglebutton Android: id = "@ + ID/tbmute" Android: layout_width = "fill_parent" Android: layout_height = "wrap_content" Android: texton = "mute" Android: textoff = "normal" Android: checked = "true" Android: layout_gravity = "center_vertical"/> <button Android: Id = "@ + ID/btnupper" Android: text = "increase volume" Android: layout_width = "wrap_content" Android: layout_height = "wrap_content"/> <button Android: Id = "@ + ID/btnlower" Android: text = "" Android: layout_width = "wrap_content" Android: layout_height = "wrap_content"/> </linearlayout>