邯郸学校网站建设/打开百度网站

步骤：

1、 获取ActivityThread中保存的所有的ActivityRecord
2 、从ActivityRecord中获取状态不是pause的Activity并返回，这个Activity就是当前处于活动状态的Activity

具体代码：

public static Activity getActivity() {Class activityThreadClass = null;try {activityThreadClass = Class.forName("android.app.ActivityThread");Object activityThread = activityThreadClass.getMethod("currentActivityThread").invoke(null);Field activitiesField = activityThreadClass.getDeclaredField("mActivities");activitiesField.setAccessible(true);Map activities = (Map) activitiesField.get(activityThread);for (Object activityRecord : activities.values()) {Class activityRecordClass = activityRecord.getClass();Field pausedField = activityRecordClass.getDeclaredField("paused");pausedField.setAccessible(true);if (!pausedField.getBoolean(activityRecord)) {Field activityField = activityRecordClass.getDeclaredField("activity");activityField.setAccessible(true);Activity activity = (Activity) activityField.get(activityRecord);return activity;}}} catch (ClassNotFoundException e) {e.printStackTrace();} catch (NoSuchMethodException e) {e.printStackTrace();} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();} catch (NoSuchFieldException e) {e.printStackTrace();}return null;
}