在一个应用中,或一个Service 、Receiver中判断一个应用是否正在运行,以便进行一些相关的处理。

这个时候我们需要得到一个ActivityManager,这个Manager顾名思意就是管理Activity的,它有一个方法叫getRunningTasks,可以得到当前系统正在运行的Task的列表,代码如下:
- ActivityManager am = (ActivityManager)context.getSystemService(Context.ACTIVITY_SERVICE);
 - List
 list = am.getRunningTasks(100); - for (RunningTaskInfo info : list) {
 - if (info.topActivity.getPackageName().equals(MY_PKG_NAME) && info.baseActivity.getPackageName().equals(MY_PKG_NAME)) {
 - isAppRunning = true;
 - //find it, break
 - break;
 - }
 - }
 
100表示取的最大的任务数,info.topActivity表示当前正在运行的Activity,info.baseActivity表系统后台有此 进程在运行,具体要做如何判断就看自已的业务需求。这个类还有更多的方法可以取得系统运行的服务、内存使用情况等的方法,请各位自行查找。
有一点要注意,如果想正常运行此方法,请在你的 AndroidManifest.xml 中加入:
否则可能会有exception抛出。
- //判断应用是否在运行
 - ActivityManager am = (ActivityManager)context.getSystemService(Context.ACTIVITY_SERVICE);
 - List
 list = am.getRunningTasks(100); - boolean isAppRunning = false;
 - String MY_PKG_NAME = "com.cyberblue.iitag";
 - for (RunningTaskInfo info : list) {
 - if (info.topActivity.getPackageName().equals(MY_PKG_NAME) || info.baseActivity.getPackageName().equals(MY_PKG_NAME)) {
 - isAppRunning = true;
 - Log.i(TAG,info.topActivity.getPackageName() + " info.baseActivity.getPackageName()="+info.baseActivity.getPackageName());
 - break;
 - }
 - }
 - //运行中才去重启蓝牙,否则会导致安装了这个应用后蓝牙无法关闭
 - if(isAppRunning){
 - BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
 - if (!mBluetoothAdapter.isEnabled()) {
 - // enable()打开蓝牙,这个方法打开蓝牙不会弹出提示
 - mBluetoothAdapter.enable();
 - }
 - }
 
Android系统内部状态信息的相关api: 
得到ActivityManager :
- ActivityManager activityManager = (ActivityManager)this.getSystemService(ACTIVITY_SERVICE)
 
这个位查到底是什么信息:
- ConfigurationInfo configurationInfo = activityManager.getDeviceConfigurationInfo();
 
获取进程内存状态的信息:
- Debug.MemoryInfo[] processMemoryInfo = activityManager.getProcessMemoryInfo(processIds);
 
获取当前运行的service信息:
- List
 runningServiceInfos = activityManager.getRunningServices(MaxValue); 
获取当前运行的任务信息:
- List
 runningTaskInfos = activityManager.getRunningTasks(MaxValue); 
其中runningTaskInfos 的 topActivity就是当前Task的活跃Activity 
在getRunningTasks()所返回的Task队列中系统会根据这些Task的活跃度有一个排序,越活跃越是靠前。第一个就是当前活动的Task
- /**
 - * 检测某ActivityUpdate是否在当前Task的栈顶
 - */
 - public boolean isTopActivy(String cmdName){
 - ActivityManager manager = (ActivityManager) context.getSystemService(ACTIVITY_SERVICE);
 - List
 runningTaskInfos = manager.getRunningTasks(1); - String cmpNameTemp = null;
 - if(null != runningTaskInfos){
 - cmpNameTemp=(runningTaskInfos.get(0).topActivity).toString);
 - Log.e("cmpname","cmpname:"+cmpName);
 - }
 - if(null == cmpNameTemp)return false;
 - return cmpNameTemp.equals(cmdName);
 - }
 
最后在应用中添加所需的权限:
- /**get the launcher status */
 - private boolean isLauncherRunnig(Context context) {
 - boolean result = false ;
 - List
 names = getAllTheLauncher(); - ActivityManager mActivityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE) ;
 - List
 appList = mActivityManager.getRunningAppProcesses() ; - for (RunningAppProcessInfo running : appList) {
 - if (running.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
 - for (int i = 0; i < names.size(); i++) {
 - if (names.get(i).equals(running.processName)) {
 - result = true ;
 - break;
 - }
 - }
 - }
 - }
 - return result ;
 - }
 
- private List
 getAllTheLauncher(){ - List
 names = null; - PackageManager pkgMgt = this.getPackageManager();
 - Intent it = new Intent(Intent.ACTION_MAIN);
 - it.addCategory(Intent.CATEGORY_HOME);
 - List
 ra =pkgMgt.queryIntentActivities(it,0); - if(ra.size() != 0){
 - names = new ArrayList
 (); - }
 - for(int i=0;i< ra.size();i++)
 - {
 - String packageName = ra.get(i).activityInfo.packageName;
 - names.add(packageName);
 - }
 - return names;
 - }
 
android 取当前显示的activity :
- ActivityManager am = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
 - ComponentName cn = am.getRunningTasks(1).get(0).topActivity;
 - Log.d("", "pkg:"+cn.getPackageName());
 - Log.d("", "cls:"+cn.getClassName());
 
Android如何判断程序是否在前台运行:
- private boolean isTopActivity(){
 - List
 tasksInfo = activityManager.getRunningTasks(1); - if(tasksInfo.size() > 0){
 - //应用程序位于堆栈的顶层
 - if(packageName.equals(tasksInfo.get(0).topActivity.getPackageName())){
 - return true;
 - }
 - }
 - return false;
 - }