MonoDroid学习笔记（十三）—— 自制任务管理器，获取正在运行的程序与服务

Android操作系统并没有提供任务管理程序，无从得知后台有哪些程序正在运行，但提供了正在运行的服务列表。这次我们来用MonoDroid来获取手机中正在运行的程序及服务，用ListView列出来，点击ListView的项可以实现关闭程序或服务。

这里我没有实现实时获取，而是通过点击两个按钮时才进行获取，布局文件如下：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
                android:layout_width="fill_parent"
                android:layout_height="fill_parent">
  <Button android:id="@+id/btnGetTask"
          android:text="正在运行的程序"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"/>
  <Button android:id="@+id/btnGetService"
          android:text="正在运行的服务"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_toRightOf="@id/btnGetTask"/>
  <ListView android:id="@+id/lvTasks"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_below="@id/btnGetTask"></ListView>
</RelativeLayout>

要获取正在运行的程序，需使用ActivityManager类的GetRunningTasks方法，它的参数指定需要取出的任务数，由于资源有限，所以我们这里设置了最多取出30条任务：

    public class Activity1 : Activity
    {
        List<string> list = new List<string>();
        IList<ActivityManager.RunningTaskInfo> listRunningTasks;
        ActivityManager am;
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            SetContentView(Resource.Layout.Main);
            Button btnGetTask = FindViewById<Button>(Resource.Id.btnGetTask);
            Button btnGetService = FindViewById<Button>(Resource.Id.btnGetService);
            ListView lvTasks = FindViewById<ListView>(Resource.Id.lvTasks);
            am = this.GetSystemService(ActivityService) as ActivityManager;
            btnGetTask.Click += (sender, e) => 
            {
                contentShown = 1;
                try
                {
                    list.Clear();
                    lvTasks.Adapter = null;
                    listRunningTasks = am.GetRunningTasks(30);
                    int index = 1;
                    foreach (ActivityManager.RunningTaskInfo task in listRunningTasks)
                    {
                        list.Add(string.Format("{0}:{1}(ID={2})", index++, task.BaseActivity.ClassName, task.Id));
                    }
                    ArrayAdapter<string> adapter = new ArrayAdapter<string>(this, Android.Resource.Layout.SimpleListItem1, list);
                    if (adapter.Count == 0)
                    {
                        Toast.MakeText(this, "当前没有任何程序运行", ToastLength.Long).Show();
                    }
                    else
                    {
                        lvTasks.Adapter = adapter;
                    }
                }
                catch (SecurityException)
                {
                    Toast.MakeText(this, "没有获取运行程序的权限", ToastLength.Long).Show();
                }
                catch (System.Exception ex)
                {
                    MessageBox.ShowErrorMessage(this, ex);
                }
            };
            lvTasks.ItemClick += (sender, e) => 
            {
                    MessageBox.Confirm(this, "提示", "确定关闭此程序吗?", (s2, e2) =>
                    {
                        am.RestartPackage(listRunningTasks[e.Position].BaseActivity.PackageName);
                        btnGetTask.PerformClick();
                    }, (s3, e3) => { });
            };
        }
    }

注意要获取任务，必需要在AndroidManifest.xml中添加GET_Tasks权限，而要关闭程序，我们这里使用的是ActivityManager类的RestartPackage方法，根据程序的包名称来关闭，所以要添加RESTART_PACKAGES权限：

  <uses-permission android:name="android.permission.GET_TASKS" />
  <uses-permission android:name="android.permission.RESTART_PACKAGES" />

效果图：

下面我们来实现获取运行中服务的效果。获取服务与获取程序差不多，只要把GetRunningTasks改为GetRunningServices即可，同样我们还是取出30条。由于是在同一个ListView中显示，在单击列表项时需要区分单击的是程序还是服务，所以我们增加一个字段contentShown加以区分，contentShown=1时表示程序，contentShown=2时表示服务，完整的代码如下：

    public class Activity1 : Activity
    {
        List<string> list = new List<string>();
        IList<ActivityManager.RunningTaskInfo> listRunningTasks;
        IList<ActivityManager.RunningServiceInfo> listRunningServices;
        ActivityManager am;
        int contentShown = 0;
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            SetContentView(Resource.Layout.Main);
            Button btnGetTask = FindViewById<Button>(Resource.Id.btnGetTask);
            Button btnGetService = FindViewById<Button>(Resource.Id.btnGetService);
            ListView lvTasks = FindViewById<ListView>(Resource.Id.lvTasks);
            am = this.GetSystemService(ActivityService) as ActivityManager;
            btnGetTask.Click += (sender, e) => 
            {
                contentShown = 1;
                try
                {
                    list.Clear();
                    lvTasks.Adapter = null;
                    listRunningTasks = am.GetRunningTasks(30);
                    int index = 1;
                    foreach (ActivityManager.RunningTaskInfo task in listRunningTasks)
                    {
                        list.Add(string.Format("{0}:{1}(ID={2})", index++, task.BaseActivity.ClassName, task.Id));
                    }
                    ArrayAdapter<string> adapter = new ArrayAdapter<string>(this, Android.Resource.Layout.SimpleListItem1, list);
                    if (adapter.Count == 0)
                    {
                        Toast.MakeText(this, "当前没有任何程序运行", ToastLength.Long).Show();
                    }
                    else
                    {
                        lvTasks.Adapter = adapter;
                    }
                }
                catch (SecurityException)
                {
                    Toast.MakeText(this, "没有获取运行程序的权限", ToastLength.Long).Show();
                }
                catch (System.Exception ex)
                {
                    MessageBox.ShowErrorMessage(this, ex);
                }
            };
            btnGetService.Click += (sender, e) => 
            {
                contentShown = 2;
                try
                {
                    lvTasks.Adapter = null;
                    listRunningServices = am.GetRunningServices(30);
                    int index = 1;
                    list.Clear();
                    foreach (ActivityManager.RunningServiceInfo service in listRunningServices)
                    {
                        list.Add(string.Format("{0}:{1}(ID={2})", index++, service.Process, service.Pid));
                    }
                    ArrayAdapter<string> adapter = new ArrayAdapter<string>(this, Android.Resource.Layout.SimpleListItem1, list);
                    if (adapter.Count == 0)
                    {
                        Toast.MakeText(this, "当前没有任何服务运行", ToastLength.Long).Show();
                    }
                    else
                    {
                        lvTasks.Adapter = adapter;
                    }
                }
                catch (SecurityException)
                {
                    Toast.MakeText(this, "没有获取运行服务的权限", ToastLength.Long).Show();
                }
                catch (System.Exception ex)
                {
                    MessageBox.ShowErrorMessage(this, ex);
                }
            };
            lvTasks.ItemClick += (sender, e) => 
            {
                if (contentShown == 1)
                {
                    MessageBox.Confirm(this, "提示", "确定关闭此程序吗?", (s2, e2) =>
                    {
                        am.RestartPackage(listRunningTasks[e.Position].BaseActivity.PackageName);
                        btnGetTask.PerformClick();
                    }, (s3, e3) => { });
                }
                else if (contentShown == 2)
                {
                    MessageBox.Confirm(this, "提示", "确定关闭此服务吗?", (s2, e2) =>
                    {
                        am.RestartPackage(listRunningServices[e.Position].Service.PackageName);
                        btnGetService.PerformClick();
                    }, (s3, e3) => { });
                }
            };
        }
    }