作为群主移除群成员 没有权限 是什么问题

if (!group.getOwner().equals(EMClient.getInstance().getCurrentUser())) {

					// if current user is not group admin, hide add/remove btn

					convertView.setVisibility(View.INVISIBLE);

				} 

protected void deleteMembersFromGroup(final String username) {

						final ProgressDialog deleteDialog = new ProgressDialog(GroupDetailsActivity.this);

						deleteDialog.setMessage(st13);

						deleteDialog.setCanceledOnTouchOutside(false);

						deleteDialog.show();

						new Thread(new Runnable() {



							@Override

							public void run() {

								try {

									// 删除被选中的成员

								    EMClient.getInstance().groupManager().removeUserFromGroup(groupId, username);

									isInDeleteMode = false;

									runOnUiThread(new Runnable() {



										@Override

										public void run() {

											deleteDialog.dismiss();

											refreshMembers();

											((TextView) findViewById(R.id.group_name)).setText(group.getGroupName() + "("

													+ group.getAffiliationsCount() + st);

										}

									});

								} catch (final Exception e) {

									deleteDialog.dismiss();

									runOnUiThread(new Runnable() {

										public void run() {

											Toast.makeText(getApplicationContext(), st14 + e.getMessage(), 1).show();

										}

									});

								}



							}

						}).start();