Java 如何在Android中使用切换按钮停止后台服务?
我正在后台运行服务,单击切换按钮,服务将停止并启动。服务将在第一个活动中启动,单击切换按钮,服务将在另一个活动中停止。当我运行应用程序时,服务将在第一个活动中自动启动,我将在onCreate()中启动第一个活动和另一个活动切换按钮状态中的方法已处于打开状态,但当我切换按钮将关闭服务停止,但当我返回第一个活动时,服务将再次启动。请任何人帮助我。这是我的代码Java 如何在Android中使用切换按钮停止后台服务?,java,android,Java,Android,我正在后台运行服务,单击切换按钮,服务将停止并启动。服务将在第一个活动中启动,单击切换按钮,服务将在另一个活动中停止。当我运行应用程序时,服务将在第一个活动中自动启动,我将在onCreate()中启动第一个活动和另一个活动切换按钮状态中的方法已处于打开状态,但当我切换按钮将关闭服务停止,但当我返回第一个活动时,服务将再次启动。请任何人帮助我。这是我的代码 public class MyService extends Service { private static final Strin
public class MyService extends Service
{
private static final String TAG = "MyService";
MediaPlayer player;
private final String StrMyService="myservice";
@Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public void onCreate() {
Toast.makeText(this, "My Service Created", Toast.LENGTH_LONG).show();
Log.d(TAG, "onCreate");
player = MediaPlayer.create(this, R.raw.braincandy);
player.setLooping(false); // Set looping
}
@Override
public void onDestroy() {
Toast.makeText(this, "My Service Stopped", Toast.LENGTH_LONG).show();
Log.d(TAG, "onDestroy");
player.stop();
}
@Override
public void onStart(Intent intent, int startid) {
Toast.makeText(this, "My Service Started", Toast.LENGTH_LONG).show();
Log.d(TAG, "onStart");
player.start();
}
}
public class Service_Demo extends Activity implements OnClickListener
{
private static final String TAG = "ServicesDemo";
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
System.out.println("In OnCreate(");
startService(new Intent(this, MyService.class));
}
}
public class Toggle_Activity extends Activity
{
ToggleButton tgButton;
private boolean isService=false;
private String strService;
public final String service_Prefs="servicePrefs";
private static final String StrMyService = "zdf";
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.toggle);
final SharedPreferences servicePrefs=this.getSharedPreferences("Service_Prefs",MODE_WORLD_READABLE);
strService=servicePrefs.getString(StrMyService , "myservice");
Log.e("",""+strService);
final boolean mBool = servicePrefs.getBoolean("myservice", true);
Log.e("Boolean Value mBool","="+mBool);
Boolean b = mBool;
Log.e("Update pref", b.toString());
tgButton = (ToggleButton)findViewById(R.id.toggleButton);
tgButton.setChecked(mBool);
final boolean mBool1 = servicePrefs.getBoolean("myservice", false);
final Boolean c = mBool1;
Log.e("Update pref", c.toString());
tgButton=(ToggleButton)findViewById(R.id.toggleButton);
tgButton.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v)
{
// TODO Auto-generated method stub
if(tgButton.isChecked())
{
startService(new Intent(Toggle_Activity.this , MyService.class));
System.out.println("Service is started in togglr button");
}
else
{
stopService(new Intent(Toggle_Activity.this,MyService.class));
System.out.println("Service is stopped in togglr button");
}
}
});
}
}
在第一个活动中,您将startService(newintent(这个,MyService.class))放在onresume中
从oncreate中,我找到了最好的方法。我基本上使用共享的首选项和侦听器将切换按钮和服务链接在一起。我将此共享首选项称为“service_running”,然后在活动
onCreate()
方法中实现我的侦听器,切换按钮出现在该方法中(在本例中,MainActivity
)
在我的onCreate()
中,我做了以下工作:
// set toggle button based on service running
final ToggleButton toggle = (ToggleButton)findViewById(R.id.toggleButton);
toggle.setChecked(serviceRunning(SendService.class));
toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
public void onCheckedChanged (CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
startSendService();
}
else {
stopSendService();
}
}
});
// set shared pref listener for toggle
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.OnSharedPreferenceChangeListener myPrefListner = new SharedPreferences.OnSharedPreferenceChangeListener(){
public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
if (key.equals("service_running")) {
toggle.setChecked(prefs.getBoolean("service_running", false));
}
}
};
prefs.registerOnSharedPreferenceChangeListener(myPrefListner);
startSendService()
和stopSendService()
只需启动或停止我的服务,具体取决于我的服务是否正在运行以及是否具有正确的应用程序权限
以下是检查服务是否正在运行的方法(归功于@geekQ in):
当您在Toggle_活动中按back键时,是否调用了Service_Demo onCreate?我是否可以解释为什么要将其保留在onresume from onCreate中。
private boolean serviceRunning (Class<?> serviceClass) {
// check if a service class is currently running
ActivityManager manager = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);
for (ActivityManager.RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
if (serviceClass.getName().equals(service.service.getClassName())) {
return true;
}
}
return false;
}
getPreferenceScreen().removePreference(findPreference("service_running"));