/**
 * 判断是有悬浮框权限
 * @return
 */
public static boolean canDrawOverlays(Context context) {
try {
return Settings.canDrawOverlays(context);
 } catch (NoSuchMethodError e) {
 }
 }
/**
 * 判断是否缺少权限
 * @param permission
 * @return
 */
public static boolean checkSelfPermission(String permission) {
return ContextCompat.checkSelfPermission(ApplicationContext.getInstance(), "android.permission.SYSTEM_ALERT_WINDOW") ==
 PackageManager.PERMISSION_GRANTED;
 }


public static boolean checkPermission(String permission) {

return (PackageManager.PERMISSION_GRANTED ==
 ApplicationContext.getInstance().getPackageManager().checkPermission("android.permission.SYSTEM_ALERT_WINDOW", ApplicationContext.getInstance().getPackageName()));

 }


/**
 * 4.4 以上可以直接判断准确
 *
 * 4.4 以下非MIUI直接返回true
 *
 * 4.4 以下MIUI 可 判断 上一次打开app 时 是否开启了悬浮窗权限
 *
 * @param context
 * @return
 */
//OP_SYSTEM_ALERT_WINDOW=24 op = 24
public static boolean checkOp(Context context, int op) {
final int version = Build.VERSION.SDK_INT;

 if (version >= 19) {
 AppOpsManager manager = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
 try {

 Class<?> spClazz = Class.forName(manager.getClass().getName());
 Method method = manager.getClass().getDeclaredMethod("checkOp", int.class, int.class, String.class);
 int property = (Integer) method.invoke(manager, op,
 Binder.getCallingUid(), context.getPackageName());

 if (AppOpsManager.MODE_ALLOWED == property) {
return true;
 } else {
return false;
 }
 } catch (Exception e) {

 }
 } else {

 }
return true;
 }


/**
 * 判断 悬浮窗口权限是否打开
 *
 * @param context
 * @return true 允许 false禁止
 */
public static boolean getAppOps(Context context) {
try {
 Object object = context.getSystemService("appops");
 if (object == null) {
return false;
 }
 Class localClass = object.getClass();
 Class[] arrayOfClass = new Class[3];
 arrayOfClass[0] = Integer.TYPE;
 arrayOfClass[1] = Integer.TYPE;
 arrayOfClass[2] = String.class;
 Method method = localClass.getMethod("checkOp", arrayOfClass);
 if (method == null) {
return false;
 }
 Object[] arrayOfObject1 = new Object[3];
 arrayOfObject1[0] = Integer.valueOf(24);
 arrayOfObject1[1] = Integer.valueOf(Binder.getCallingUid());
 arrayOfObject1[2] = context.getPackageName();
 int m = ((Integer) method.invoke(object, arrayOfObject1)).intValue();
 return m == AppOpsManager.MODE_ALLOWED;
 } catch (Exception ex) {

 }
return false;
 }