使用情景：最近有個需求是統計后台應用運行時間，如果一個應用在后台運行超過一定時間就Kill掉進程，達到省電的目的。此時就可以使用PkgUsageStats這個類來實現啦！
通過com.android.internal.os.PkgUsageStats這個類可以得到一個應用程序的啟動次數，運行時間等信息，功能強大，但是google並沒有將這個類作為API接口提供給開發者，如果在android 源碼 下開發，可以通過以下代碼來使用這個類：
import com.android.internal.app.IUsageStats;
import com.android.internal.os.PkgUsageStats;
//比較兩個應用程序的啟動次數和運行時間
public final int compare(ApplicationInfo a, ApplicationInfo b) {
ComponentName aName = a.intent.getComponent();
ComponentName bName = b.intent.getComponent();
int result = 0;
// get usagestats service
IUsageStats mUsageStatsService = IUsageStats.Stub
.asInterface(ServiceManager.getService("usagestats"));
try {
// get PkgUsageStats
PkgUsageStats aStats = mUsageStatsService.getPkgUsageStats(aName);
PkgUsageStats bStats = mUsageStatsService.getPkgUsageStats(bName);
if (aStats != null && bStats != null) {
if ((aStats.launchCount > bStats.launchCount)
|| ((aStats.launchCount == bStats.launchCount) && (aStats.usageTime > bStats.usageTime)))
result = -1;
else if ((aStats.launchCount < bStats.launchCount)
|| ((aStats.launchCount == bStats.launchCount) && (aStats.usageTime < bStats.usageTime)))
result = 1;
else {
result = 0;
}
} else if (aStats != null && bStats == null) {
result = -1;
} else if (aStats == null && bStats != null) {
result = 1;
}
} catch (RemoteException e) {
Log.i("TAG", "get package usage stats fail");
}
return result;
}
那么如果想在sdk中使用這個 類要如果作呢--可以使用反射 的方法，代碼如下：
public final int compare(ApplicationInfo a, ApplicationInfo b) {
ComponentName aName = a.intent.getComponent();
ComponentName bName = b.intent.getComponent();
int aLaunchCount, bLaunchCount;
long aUseTime, bUseTime;
int result = 0;
try {
// 獲得ServiceManager類
Class ServiceManager = Class
.forName("android.os.ServiceManager");
// 獲得ServiceManager的getService方法
Method getService = ServiceManager.getMethod("getService",
java.lang.String.class);
// 調用getService獲取RemoteService
Object oRemoteService = getService.invoke(null, "usagestats");
// 獲得IUsageStats.Stub類
Class cStub = Class
.forName("com.android.internal.app.IUsageStats$Stub");
// 獲得asInterface方法
Method asInterface = cStub.getMethod("asInterface",
android.os.IBinder.class);
// 調用asInterface方法獲取IUsageStats對象
Object oIUsageStats = asInterface.invoke(null, oRemoteService);
// 獲得getPkgUsageStats(ComponentName)方法
Method getPkgUsageStats = oIUsageStats.getClass().getMethod(
"getPkgUsageStats", ComponentName.class);
// 調用getPkgUsageStats 獲取PkgUsageStats對象
Object aStats = getPkgUsageStats.invoke(oIUsageStats, aName);
Object bStats = getPkgUsageStats.invoke(oIUsageStats, bName);
// 獲得PkgUsageStats類
Class PkgUsageStats = Class
.forName("com.android.internal.os.PkgUsageStats");
aLaunchCount = PkgUsageStats.getDeclaredField("launchCount")
.getInt(aStats);
bLaunchCount = PkgUsageStats.getDeclaredField("launchCount")
.getInt(bStats);
aUseTime = PkgUsageStats.getDeclaredField("usageTime").getLong(
aStats);
bUseTime = PkgUsageStats.getDeclaredField("usageTime").getLong(
bStats);
if ((aLaunchCount > bLaunchCount)
|| ((aLaunchCount == bLaunchCount) && (aUseTime > bUseTime)))
result = 1;
else if ((aLaunchCount < bLaunchCount)
|| ((aLaunchCount == bLaunchCount) && (aUseTime < bUseTime)))
result = -1;
else {
result = 0;
}
} catch (Exception e) {
Log.e("###", e.toString(), e);
}
return result;
}
如何看自己的android的詳細使用信息：
我們使用Andoroid手機時想看看自己的手機的使用情況，那么我們又如何去操作呢？也是必需得像程序這樣要自己寫一個程序才能查看吧，如果用戶不是 編程 的，那得怎么辦，呵，其實我們查看自己的手機使用詳情是沒有那么復雜的，今天androidkaifa.com就會大家說一下如何查詢自己的手機的使用情況，下面是具體的查看方法，
其實查看方法非常簡單，直接進入 Android 的工程模式即可，操作步驟如下：（筆者的android手機 系統 是4.2）
1、首先進入Android手機操作系統的撥號界面，直接輸入“*#*#4636#*#*”（不加引號）即可以快速進入Android操作系統的工程測試模式。
2、在“測試”模式菜單中有手機信息“Phone information”、電池信息“Battery information”、WI-FI信息“WI-FI information”、使用狀態“Usage statistics”四個選項。
3、我們點擊選擇第二項“Battery information”進入電池信息，然后就可以看到手機電池的詳細信息了，其中包括電量等級、電池狀態、溫度、電池材質、電壓等等信息。
4: 我們相應點擊其實的選擇就可以看到其實的相應的使用詳細信息
==================================================================================================================
import com.android.internal.app.IUsageStats;
import com.android.settings.R;
import android.app.Activity;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.os.Bundle;
import android.os.RemoteException;
import android.os.ServiceManager;
import com.android.internal.os.PkgUsageStats;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.AdapterView.OnItemSelectedListener;
/**
* Activity to display package usage statistics.
*/
public class UsageStats extends Activity implements OnItemSelectedListener {
private static final String TAG="UsageStatsActivity";
private static final boolean localLOGV = true;
private Spinner mTypeSpinner;
private ListView mListView;
private IUsageStats mUsageStatsService;
private LayoutInflater mInflater;
private UsageStatsAdapter mAdapter;
private PackageManager mPm;
public static class AppNameComparator implements Comparator {
Map mAppLabelList;
AppNameComparator(Map appList) {
mAppLabelList = appList;
}
public final int compare(PkgUsageStats a, PkgUsageStats b) {
String alabel = mAppLabelList.get(a.packageName).toString();
String blabel = mAppLabelList.get(b.packageName).toString();
return alabel.compareTo(blabel);
}
}
public static class LaunchCountComparator implements Comparator {
public final int compare(PkgUsageStats a, PkgUsageStats b) {
// return by descending order
return b.launchCount - a.launchCount;
}
}
public static class UsageTimeComparator implements Comparator {
public final int compare(PkgUsageStats a, PkgUsageStats b) {
long ret = a.usageTime-b.usageTime;
if (ret == 0) {
return 0;
}
if (ret < 0) {
return 1;
}
return -1;
}
}
// View Holder used when displaying views
static class AppViewHolder {
TextView pkgName;
TextView launchCount;
TextView usageTime;
}
class UsageStatsAdapter extends BaseAdapter {
// Constants defining order for display order
private static final int _DISPLAY_ORDER_USAGE_TIME = 0;
private static final int _DISPLAY_ORDER_LAUNCH_COUNT = 1;
private static final int _DISPLAY_ORDER_APP_NAME = 2;
private int mDisplayOrder = _DISPLAY_ORDER_USAGE_TIME;
private List mUsageStats;
private LaunchCountComparator mLaunchCountComparator;
private UsageTimeComparator mUsageTimeComparator;
private AppNameComparator mAppLabelComparator;
private HashMap mAppLabelMap;
UsageStatsAdapter() {
mUsageStats = new ArrayList();
mAppLabelMap = new HashMap();
PkgUsageStats[] stats;
try {
stats = mUsageStatsService.getAllPkgUsageStats();
} catch (RemoteException e) {
Log.e(TAG, "Failed initializing usage stats service");
return;
}
if (stats == null) {
return;
}
for (PkgUsageStats ps : stats) {
mUsageStats.add(ps);
// load application labels for each application
CharSequence label;
try {
ApplicationInfo appInfo = mPm.getApplicationInfo(ps.packageName, 0);
label = appInfo.loadLabel(mPm);
} catch (NameNotFoundException e) {
label = ps.packageName;
}
mAppLabelMap.put(ps.packageName, label);
}
// Sort list
mLaunchCountComparator = new LaunchCountComparator();
mUsageTimeComparator = new UsageTimeComparator();
mAppLabelComparator = new AppNameComparator(mAppLabelMap);
sortList();
}
public int getCount() {
return mUsageStats.size();
}
public Object getItem(int position) {
return mUsageStats.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
// A ViewHolder keeps references to children views to avoid unneccessary calls
// to findViewById() on each row.
AppViewHolder holder;
// When convertView is not null, we can reuse it directly, there is no need
// to reinflate it. We only inflate a new View when the convertView supplied
// by ListView is null.
if (convertView == null) {
convertView = mInflater.inflate(R.layout.usage_stats_item, null);
// Creates a ViewHolder and store references to the two children views
// we want to bind data to.
holder = new AppViewHolder();
holder.pkgName = (TextView) convertView.findViewById(R.id.package_name);
holder.launchCount = (TextView) convertView.findViewById(R.id.launch_count);
holder.usageTime = (TextView) convertView.findViewById(R.id.usage_time);
convertView.setTag(holder);
} else {
// Get the ViewHolder back to get fast access to the TextView
// and the ImageView.
holder = (AppViewHolder) convertView.getTag();
}
// Bind the data efficiently with the holder
PkgUsageStats pkgStats = mUsageStats.get(position);
if (pkgStats != null) {
CharSequence label = mAppLabelMap.get(pkgStats.packageName);
holder.pkgName.setText(label);
holder.launchCount.setText(String.valueOf(pkgStats.launchCount));
holder.usageTime.setText(String.valueOf(pkgStats.usageTime)+" ms");
} else {
Log.w(TAG, "No usage stats info for package:" + position);
}
return convertView;
}
void sortList(int sortOrder) {
if (mDisplayOrder == sortOrder) {
// do nothing
return;
}
mDisplayOrder= sortOrder;
sortList();
}
private void sortList() {
if (mDisplayOrder == _DISPLAY_ORDER_USAGE_TIME) {
if (localLOGV) Log.i(TAG, "Sorting by usage time");
Collections.sort(mUsageStats, mUsageTimeComparator);
} else if (mDisplayOrder == _DISPLAY_ORDER_LAUNCH_COUNT) {
if (localLOGV) Log.i(TAG, "Sorting launch count");
Collections.sort(mUsageStats, mLaunchCountComparator);
} else if (mDisplayOrder == _DISPLAY_ORDER_APP_NAME) {
if (localLOGV) Log.i(TAG, "Sorting by application name");
Collections.sort(mUsageStats, mAppLabelComparator);
}
notifyDataSetChanged();
}
}
/** Called when the activity is first created. */
protected void onCreate(Bundle icicle) {
super.onCreate(icicle);
mUsageStatsService = IUsageStats.Stub.asInterface(ServiceManager.getService("usagestats"));
if (mUsageStatsService == null) {
Log.e(TAG, "Failed to retrieve usagestats service");
return;
}
mInflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
mPm = getPackageManager();
setContentView(R.layout.usage_stats);
mTypeSpinner = (Spinner) findViewById(R.id.typeSpinner);
mTypeSpinner.setOnItemSelectedListener(this);
mListView = (ListView) findViewById(R.id.pkg_list);
// Initialize the inflater
mAdapter = new UsageStatsAdapter();
mListView.setAdapter(mAdapter);
}
public void onItemSelected(AdapterView parent, View view, int position,
long id) {
mAdapter.sortList(position);
}
public void onNothingSelected(AdapterView parent) {
// do nothing
}
}
轉載自http://www.2cto.com/kf/201501/371519.htm