Android 如何获得第一个运行的进程？

我正在为我的安全应用程序创建一个服务，该服务将在每秒钟后检查特定进程是否启动，并将弹出密码对话框。任何人只有在输入密码后才能使用该应用程序。我的问题是我的计时器反复显示对话框。因此，我应用“c”变量来运行此对话框一次，但这只会在启动应用程序后出现。之后！应用程序正在直接打开，而不首先显示对话框`

private static Timer timer = new Timer(); 
        private Context ctx;
      private  int c=0;
    @Override
    public IBinder onBind(Intent arg0) {
        // TODO Auto-generated method stub
        return null;
    }
      public void onCreate() 
        {
              super.onCreate();
              ctx = this; 
              startService();
        }

        private void startService()
        {           
            timer.scheduleAtFixedRate(new mainTask(), 0, 5000);
        }

        private class mainTask extends TimerTask
        { 
            public void run() 
            {
                toastHandler.sendEmptyMessage(0);
            }
        }   
    @Override
    public int onStartCommand(Intent intent, int flag,int startId){
        /* Timer timer = new Timer();
            timer.scheduleAtFixedRate(new TimerTask() {
                public void run() {   


                                dial();
                            }
                        }                       
                     }
                   }, 0, 1000);*/
        return START_STICKY;    
    }
    @Override
    public void onDestroy(){

        super.onDestroy();
        timer.cancel();
        Toast.makeText(this, "Service Stoped", Toast.LENGTH_LONG).show();
    }
     private final Handler toastHandler = new Handler()
        {
            @Override
            public void handleMessage(Message msg)
            {
                Toast.makeText(getApplicationContext(), "test", Toast.LENGTH_SHORT).show();
                ActivityManager actvityManager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
            List<RunningAppProcessInfo> procInfos = actvityManager.getRunningAppProcesses();
            for(int i = 0; i < procInfos.size(); i++){
                if(procInfos.get(i).processName.equals("com.android.music")) {
                    Toast.makeText(getApplicationContext(), "music is running", Toast.LENGTH_LONG).show();
                  c++;
                  if(c==1){
                    int pid = android.os.Process.getUidForName("com.android.music");
                     android.os.Process.killProcess(pid);
                    Intent ii = new Intent();
                       ii.setClass(APP_SeeL_Password.this,Setappdetail.class);
                       ii.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                       startActivity(ii); 
                  }
                    //timer.cancel();
                  }
                } 
           }
        };  ` 

okb.setOnClickListener（新视图.OnClickListener（）{

}

    public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.custom_dialoge);
    LayoutParams params = getWindow().getAttributes(); 
    params.width = LayoutParams.FILL_PARENT; 
     getWindow().setAttributes((android.view.WindowManager.LayoutParams) params);
    // TODO Auto-generated method stub

EditText et=(EditText)findViewById(R.id.editText2);
  str=et.getText().toString();
  LockOrNot getpinvar=new LockOrNot(this);
     getpinvar.open();
      ptr=getpinvar.getpin(1);
     getpinvar.close();
Button okb=(Button)findViewById(R.id.button1);

    public void onClick(View arg0) {
        // TODO Auto-generated method stub

        if(str.equals(ptr)==true){
        Intent LaunchIntent = getPackageManager().getLaunchIntentForPackage("com.android.music");
        startActivity( LaunchIntent );}
    }
});
Button cancelb=(Button)findViewById(R.id.button2);
cancelb.setOnClickListener(new View.OnClickListener() {

    public void onClick(View arg0) {
        // TODO Auto-generated method stub
        Intent startMain = new Intent(Intent.ACTION_MAIN);
        startMain.addCategory(Intent.CATEGORY_HOME);
        startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        startActivity(startMain);
    }
});