As you wrote that the task is about monitoring 3-rd party applications, there is no solution other than periodically read a list of processes and detecting foreground process. You need a service for this. Unfortunately, Android does not provide means such as broadcast events for foreground process change.
The task requires a lot of code in fact, at least much more than an ordinary answer could comprise. I'm posting a part of it here, but you should address many nuances left behind the scenes, such as synchronization and persisting information between launches. This is just a skeleton.
First, lets code an application object, which is a good place to register all instance related stuff.
MonitorApp
public class MonitorApp extends Application
{
// actual store of statistics
private final ArrayList<HashMap<String,Object>> processList = new ArrayList<HashMap<String,Object>>();
// fast-access index by package name (used for lookup)
private ArrayList<String> packages = new ArrayList<String>();
public ArrayList<HashMap<String,Object>> getProcessList()
{
return processList;
}
public ArrayList<String> getPackages()
{
return packages;
}
// TODO: you need to save and load the instance data
// TODO: you need to address synchronization issues
}
Then lets draft an activity.
MonitorActivity
import static ProcessList.COLUMN_PROCESS_NAME;
import static ProcessList.COLUMN_PROCESS_PROP;
import static ProcessList.COLUMN_PROCESS_COUNT;
import static ProcessList.COLUMN_PROCESS_TIME;
public class MonitorActivity extends Activity implements MonitorService.ServiceCallback
{
private ArrayList<HashMap<String,Object>> processList;
private MonitorService backgroundService;
private MyCustomAdapter adapter = null;
private ListView listView = null;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main); // TODO: provide your layout
listView = (ListView)findViewById(R.id.id_process_listview);
createAdapter();
this.bindService(
new Intent(this, MonitorService.class),
serviceConnection,
Context.BIND_AUTO_CREATE);
}
private void createAdapter()
{
processList = ((MonitorApp)getApplication()).getProcessList();
adapter = new MyCustomAdapter(this, processList, R.layout.complex_list_item,
new String[]
{
COLUMN_PROCESS_NAME,
COLUMN_PROCESS_PROP, // TODO: you may calculate and pre-fill this field
// from COLUMN_PROCESS_COUNT and COLUMN_PROCESS_TIME
// so eliminating the need to use the custom adapter
},
new int[]
{
android.R.id.text1,
android.R.id.text2
});
listView.setAdapter(adapter);
}
// callback method invoked by the service when foreground process changed
@Override
public void sendResults(int resultCode, Bundle b)
{
adapter.notifyDataSetChanged();
}
private class MyCustomAdapter extends SimpleAdapter
{
MyCustomAdapter(Context context, List<? extends Map<String, ?>> data, int resource, String[] from, int[] to)
{
super(context, data, resource, from, to);
}
@Override
public View getView (int position, View convertView, ViewGroup parent)
{
View result = super.getView(position, convertView, parent);
// TODO: customize process statistics display
int count = (Integer)(processList.get(position).get(COLUMN_PROCESS_COUNT));
int seconds = (Integer)(processList.get(position).get(COLUMN_PROCESS_TIME));
return result;
}
}
private ServiceConnection serviceConnection = new ServiceConnection()
{
@Override
public void onServiceConnected(ComponentName className, IBinder service)
{
LocalBinder binder = (LocalBinder)service;
backgroundService = binder.getService();
backgroundService.setCallback(MonitorActivity.this);
backgroundService.start();
}
@Override
public void onServiceDisconnected(ComponentName className)
{
backgroundService = null;
}
};
@Override
public void onResume()
{
super.onResume();
if(backgroundService != null)
{
backgroundService.setCallback(this);
}
}
@Override
public void onPause()
{
super.onPause();
if(backgroundService != null)
{
backgroundService.setCallback(null);
}
}
}
The activity launches a background worker service, which does actually monitor processes. You could possibly move the service registration from the activity into the application instance. The service itself is something like this:
MonitorService
public class MonitorService extends Service
{
private boolean initialized = false;
private final IBinder mBinder = new LocalBinder();
private ServiceCallback callback = null;
private Timer timer = null;
private final Handler mHandler = new Handler();
private String foreground = null;
private ArrayList<HashMap<String,Object>> processList;
private ArrayList<String> packages;
private Date split = null;
public static int SERVICE_PERIOD = 5000; // TODO: customize (this is for scan every 5 seconds)
private final ProcessList pl = new ProcessList(this)
{
@Override
protected boolean isFilteredByName(String pack)
{
// TODO: filter processes by names, return true to skip the process
// always return false (by default) to monitor all processes
return false;
}
};
public interface ServiceCallback
{
void sendResults(int resultCode, Bundle b);
}
public class LocalBinder extends Binder
{
MonitorService getService()
{
// Return this instance of the service so clients can call public methods
return MonitorService.this;
}
}
@Override
public void onCreate()
{
super.onCreate();
initialized = true;
processList = ((MonitorApp)getApplication()).getProcessList();
packages = ((MonitorApp)getApplication()).getPackages();
}
@Override
public IBinder onBind(Intent intent)
{
if(initialized)
{
return mBinder;
}
return null;
}
public void setCallback(ServiceCallback callback)
{
this.callback = callback;
}
private boolean addToStatistics(String target)
{
boolean changed = false;
Date now = new Date();
if(!TextUtils.isEmpty(target))
{
if(!target.equals(foreground))
{
int i;
if(foreground != null && split != null)
{
// TODO: calculate time difference from current moment
// to the moment when previous foreground process was activated
i = packages.indexOf(foreground);
long delta = (now.getTime() - split.getTime()) / 1000;
Long time = (Long)processList.get(i).get(COLUMN_PROCESS_TIME);
if(time != null)
{
// TODO: add the delta to statistics of 'foreground'
time += delta;
}
else
{
time = new Long(delta);
}
processList.get(i).put(COLUMN_PROCESS_TIME, time);
}
// update count of process activation for new 'target'
i = packages.indexOf(target);
Integer count = (Integer)processList.get(i).get(COLUMN_PROCESS_COUNT);
if(count != null) count++;
else
{
count = new Integer(1);
}
processList.get(i).put(COLUMN_PROCESS_COUNT, count);
foreground = target;
split = now;
changed = true;
}
}
return changed;
}
public void start()
{
if(timer == null)
{
timer = new Timer();
timer.schedule(new MonitoringTimerTask(), 500, SERVICE_PERIOD);
}
// TODO: startForeground(srvcid, createNotification(null));
}
public void stop()
{
timer.cancel();
timer.purge();
timer = null;
}
private class MonitoringTimerTask extends TimerTask
{
@Override
public void run()
{
fillProcessList();
ActivityManager activityManager = (ActivityManager)MonitorService.this.getSystemService(ACTIVITY_SERVICE);
List<RunningTaskInfo> taskInfo = activityManager.getRunningTasks(1);
String current = taskInfo.get(0).topActivity.getPackageName();
// check if current process changed
if(addToStatistics(current) && callback != null)
{
final Bundle b = new Bundle();
// TODO: pass necessary info to UI via bundle
mHandler.post(new Runnable()
{
public void run()
{
callback.sendResults(1, b);
}
});
}
}
}
private void fillProcessList()
{
pl.fillProcessList(processList, packages);
}
}
The service utilizes a helper class for building process lists.
ProcessList
public abstract class ProcessList
{
// process package name
public static final String COLUMN_PROCESS_NAME = "process";
// TODO: arbitrary property (can be user-fiendly name)
public static final String COLUMN_PROCESS_PROP = "property";
// number of times a process has been activated
public static final String COLUMN_PROCESS_COUNT = "count";
// number of seconds a process was in foreground
public static final String COLUMN_PROCESS_TIME = "time";
private ContextWrapper context;
ProcessList(ContextWrapper context)
{
this.context = context;
}
protected abstract boolean isFilteredByName(String pack);
public void fillProcessList(ArrayList<HashMap<String,Object>> processList, ArrayList<String> packages)
{
ActivityManager activityManager = (ActivityManager)context.getSystemService(Context.ACTIVITY_SERVICE);
List<RunningAppProcessInfo> procInfo = activityManager.getRunningAppProcesses();
HashMap<String, Object> hm;
final PackageManager pm = context.getApplicationContext().getPackageManager();
for(int i = 0; i < procInfo.size(); i++)
{
String process = procInfo.get(i).processName;
String packageList = Arrays.toString(procInfo.get(i).pkgList);
if(!packageList.contains(process))
{
process = procInfo.get(i).pkgList[0];
}
if(!packages.contains(process) && !isFilteredByName(process))
{
ApplicationInfo ai;
String applicationName = "";
for(int k = 0; k < procInfo.get(i).pkgList.length; k++)
{
String thisPackage = procInfo.get(i).pkgList[k];
try
{
ai = pm.getApplicationInfo(thisPackage, 0);
}
catch(final NameNotFoundException e)
{
ai = null;
}
if(k > 0) applicationName += " / ";
applicationName += (String)(ai != null ? pm.getApplicationLabel(ai) : "(unknown)");
}
packages.add(process);
hm = new HashMap<String, Object>();
hm.put(COLUMN_PROCESS_NAME, process);
hm.put(COLUMN_PROCESS_PROP, applicationName);
processList.add(hm);
}
}
// optional sorting
Comparator<HashMap<String, Object>> comparator = new Comparator<HashMap<String, Object>>()
{
public int compare(HashMap<String, Object> object1, HashMap
