我正在开发一个使用 v2 MapFragment 的应用程序，但我遇到了非常奇怪的行为。我已经创建了一个 MapFragment 的子类来处理一些自定义行为(处理 Marker、调整菜单选项等)，并且在第一次加载时一切正常。然后我将一个新 fragment 嵌入到我的 Activity 中，将自定义 MapFragment 推送到后台堆栈。但是，当我从后台返回 map 时，事情变得很奇怪；平移 map 变得极度滞后(我们说的是 ~1 FPS)，无论是手动拖动/缩放还是点击图钉引起的动画。 然后，如果我与溢出菜单的任何部分进行交互，即使只是打开它并再次关闭它，延迟也会立即消失。似乎没有其他方法可以解决它(除了关闭/重新打开应用程序)；与非溢出菜单项和抽屉导航交互无济于事。我从来没有见过这样的事情，也找不到以前描述过类似问题的人。欢迎任何想法、建议和/或修复。
在他们被问到之前回答几个问题:
- 是的，我正在调用我覆盖的所有生命周期方法的
super版本(onCreate()、onCreateView()[I我还返回 super 返回的内容]，以及onDestroyView())。 - 据我所知，我正在正确清理 map 。每次刷新图钉时，我都会在每个图钉上调用
remove()，然后在 map 本身上调用clean()，我在onDestroyView()还有。
最后，作为引用，这是添加新 fragment 的代码:
getFragmentManager().beginTransaction().replace(R.id.main_content_container, new JoinGroupFragment()).addToBackStack(null).commit();
当我完成它时，我只需调用:
getFragmentManager().popBackStack();
编辑:我不确定它会有多大帮助，但这是自定义 MapFragment:
public class CustomMapFragment extends MapFragment {
private static final String DIALOG_TAG = "CUSTOM_MAP_FRAGMENT_DIALOG";
private static final int DEFAULT_ZOOM = 14;
private static final int MARKER_ZOOM = 15;
private static final int DEFAULT_PADDING = 80;
private static final int ORANGE_THRESHOLD_MINUTES = 7;
private static final int BLUE_THRESHOLD_MINUTES = 20;
public static final String KEY_GROUP_NAME = "GROUP_NAME";
public static final String KEY_GROUP_ID = "GROUP_ID";
private TextView mGroupNameOverlay;
private GoogleMap mMap;
private ArrayList<Marker> mMarkers;
private Marker mSelectedMarker;
private ArrayList<Group> mAllGroups;
private Group mCurrentGroup;
private ArrayList<Location> mAllLocations;
private boolean mMapReady;
private String mUsername;
private boolean mCenterOnUser;
public CustomMapFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
mMarkers = new ArrayList<>();
mAllLocations = new ArrayList<>();
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getActivity());
mUsername = prefs.getString(PreferenceUtils.KEY_USERNAME, null);
mCenterOnUser = prefs.getBoolean(PreferenceUtils.KEY_CENTER_ON_ME, false);
mSelectedMarker = null;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
ViewGroup view = (ViewGroup)super.onCreateView(inflater, container, savedInstanceState);
if (view != null) {
// View should never be null; MapFragments have a FrameLayout as their top level parent
mGroupNameOverlay = (TextView)inflater.inflate(R.layout.group_name_overlay, view, false);
view.addView(mGroupNameOverlay);
}
Bundle results = ((MainActivity)getActivity()).getFragmentResults();
if (results != null) {
String name = results.getString(KEY_GROUP_NAME);
String id = results.getString(KEY_GROUP_ID);
if (!StringUtils.isNullOrEmpty(name) && !StringUtils.isNullOrEmpty(id)) {
mCurrentGroup = new Group(name, id);
mAllGroups.add(mCurrentGroup);
}
}
if (mCurrentGroup != null) {
updateGroupNameOverlay(mCurrentGroup.getGroupName());
}
getMapAsync(new OnMapReadyCallback() {
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
mMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
@Override
public boolean onMarkerClick(Marker marker) {
mSelectedMarker = marker;
getActivity().invalidateOptionsMenu();
return false;
}
});
mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng latLng) {
mSelectedMarker = null;
getActivity().invalidateOptionsMenu();
}
});
populateMap(true, false);
}
});
GetGroupsRequest request = new GetGroupsRequest();
request.setListener(new GetGroupsRequestListener());
RequestProcessor.getInstance(getActivity()).queueRequest(request);
return view;
}
@Override
public void onDestroyView() {
mSelectedMarker = null;
for (Marker marker : mMarkers) {
marker.remove();
}
mMarkers.clear();
mMap.clear();
mMap = null;
mMapReady = false;
super.onDestroyView();
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
if (mSelectedMarker == null) {
inflater.inflate(R.menu.menu_map, menu);
}
else {
inflater.inflate(R.menu.menu_marker, menu);
}
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.map_menu_refresh_pins:
performLocationsRequest(false);
return true;
case R.id.map_menu_recenter_zoom:
populateMap(true, true);
return true;
case R.id.map_menu_select_group:
DialogFragment selectDialog = new DialogFragment() {
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
String[] groups = new String[mAllGroups.size()];
for (int i = 0; i < groups.length; i++) {
groups[i] = mAllGroups.get(i).getGroupName();
}
return new AlertDialog.Builder(getActivity())
.setItems(groups, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
if (!mAllGroups.get(which).equals(mCurrentGroup)) {
mCurrentGroup = mAllGroups.get(which);
updateGroupNameOverlay(mCurrentGroup.getGroupName());
performLocationsRequest(true);
}
}
})
.create();
}
};
selectDialog.show(getFragmentManager(), DIALOG_TAG);
return true;
case R.id.map_menu_join_group:
getFragmentManager().beginTransaction().replace(R.id.main_content_container, new JoinGroupFragment()).addToBackStack(null).commit();
return true;
case R.id.map_menu_create_group:
CreateDialogFragment createDialog = new CreateDialogFragment();
createDialog.show(getFragmentManager(), DIALOG_TAG);
return true;
case R.id.map_marker_zoom:
if (mSelectedMarker != null) {
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(mSelectedMarker.getPosition(), MARKER_ZOOM));
}
return true;
default:
return super.onOptionsItemSelected(item);
}
}
private void performLocationsRequest(boolean autoZoom) {
GetLocationsRequest request = new GetLocationsRequest(mCurrentGroup.getGroupId());
request.setListener(new GetLocationsRequestListener(autoZoom));
RequestProcessor.getInstance(getActivity()).queueRequest(request);
}
private void updateGroupNameOverlay(final String groupName) {
if (mGroupNameOverlay != null) {
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
if (groupName == null) {
mGroupNameOverlay.setText(R.string.map_group_overlay_no_group);
}
else {
mGroupNameOverlay.setText(getString(R.string.map_group_overlay_group, groupName));
}
}
});
}
}
private void populateMap(boolean zoom, boolean animate) {
if (!mMapReady) {
mMapReady = true;
}
else {
CameraUpdate update = null;
mSelectedMarker = null;
for (Marker marker : mMarkers) {
marker.remove();
}
mMarkers.clear();
mMap.clear();
if (mAllLocations.size() == 1) {
Location location = mAllLocations.get(0);
mMarkers.add(addMarker(location));
update = CameraUpdateFactory.newLatLngZoom(new LatLng(location.getLatitude(), location.getLongitude()), DEFAULT_ZOOM);
}
else if (mAllLocations.size() > 1) {
LatLngBounds.Builder builder = new LatLngBounds.Builder();
for (Location location : mAllLocations) {
mMarkers.add(addMarker(location));
if (mCenterOnUser) {
if (location.getUsername().equals(mUsername)) {
update = CameraUpdateFactory.newLatLngZoom(new LatLng(location.getLatitude(), location.getLongitude()), DEFAULT_ZOOM);
}
}
else {
builder.include(new LatLng(location.getLatitude(), location.getLongitude()));
}
}
if (!mCenterOnUser) {
update = CameraUpdateFactory.newLatLngBounds(builder.build(), DEFAULT_PADDING);
}
}
if (update != null && zoom) {
if (animate) {
mMap.animateCamera(update);
}
else {
mMap.moveCamera(update);
}
}
}
}
private Marker addMarker(Location location) {
String timestamp;
long minutesOld = (new Date().getTime() - location.getLastReported()) / 60000;
float hue = BitmapDescriptorFactory.HUE_RED;
if (minutesOld < 1) {
timestamp = getString(R.string.map_timestamp_just_now);
}
else if (minutesOld < 2) {
timestamp = getString(R.string.map_timestamp_one_minute);
}
else {
timestamp = getString(R.string.map_timestamp_n_minutes, minutesOld);
if (minutesOld >= ORANGE_THRESHOLD_MINUTES) {
hue = BitmapDescriptorFactory.HUE_ORANGE;
}
if (minutesOld >= BLUE_THRESHOLD_MINUTES) {
hue = BitmapDescriptorFactory.HUE_BLUE;
}
}
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
return mMap.addMarker(new MarkerOptions()
.position(latLng)
.icon(BitmapDescriptorFactory.defaultMarker(hue))
.title(location.getUsername())
.snippet(timestamp));
}
private class GetGroupsRequestListener extends RequestListener<GetGroupsResponse> {
public GetGroupsRequestListener() {
super(getActivity());
}
@Override
protected void onRequestComplete(GetGroupsResponse response) {
mAllGroups = response.getGroups();
if (mAllGroups.size() > 0) {
if (mCurrentGroup == null) {
mCurrentGroup = mAllGroups.get(0);
updateGroupNameOverlay(mCurrentGroup.getGroupName());
}
performLocationsRequest(true);
}
}
}
private class GetLocationsRequestListener extends RequestListener<GetLocationsResponse> {
private boolean mmAutoZoom;
public GetLocationsRequestListener(boolean autoZoom) {
super(getActivity());
mmAutoZoom = autoZoom;
}
@Override
protected void onRequestComplete(GetLocationsResponse response) {
mAllLocations = response.getLocations();
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
populateMap(mmAutoZoom, false);
}
});
}
}
}
附言我意识到劫持 View 创建并以这种方式注入(inject)我自己的覆盖层可能不是最佳做法，但就其值(value)而言，我尝试将该部分注释掉但它没有解决问题，所以我很怀疑它是相关的。
最佳答案
我遇到过类似的问题。假设我有带有子 SupportMapFragment 的 FragmentA。通过抽屉导航菜单，我调用了一个要显示的对话框。此时 FragmentA 中的子 map 进入某种“背景模式”——它大约每秒更新两次(我在这张 map 上有动画标记，所以这种行为对我来说是众所周知的)。这种“背景”模式是通过显示任何带有覆盖的元素来打开的，例如。对话框或 AppBar 菜单，并在该元素隐藏时关闭。
在对话框中我有项目列表，点击时开始 fragment 替换事务。此时 FragmentA 正在被 FragmentB 取代。这是 OnClickListener 的代码 fragment :
final SmartFragment fragment = new SmartFragment();
FragmentManager supportFragmentManager = getActivity().getSupportFragmentManager();
supportFragmentManager
.beginTransaction()
.replace(R.id.fragment_container, fragment, SmartFragment.FRAGMENT_TAG)
.addToBackStack(null)
.commit();
dismiss();
但是在我从后台返回到 FragmentA 后，保留的 map 仍然处于“背景模式”，即使对话框不再存在。在事务之前移动 dissmiss() 语句无济于事，它看起来就像对话框在执行所有代码之前不会被关闭。因此，唯一合理的解决方案(除了直接在 map fragment 上打开“背景模式”，我找不到如何做)是延迟 fragment 事务，直到对话框真正被关闭。正如我之前假设的那样，只有当 OnClick(它是对话框的一部分)中的所有代码都被执行时才会发生，所以我们需要让事务不在它被声明的实例中完成，而是稍后，将它放在 Runnable 中:
dismiss();
final SmartFragment fragment = new SmartFragment();
Handler handler = new Handler();
final FragmentManager supportFragmentManager = getActivity().getSupportFragmentManager();
handler.post(new Runnable() {
@Override
public void run() {
supportFragmentManager
.beginTransaction()
.replace(R.id.fragment_container, fragment, StopsSmartFragment.FRAGMENT_TAG)
.addToBackStack(null)
.commit();
}
});
为此，我们需要将我们的 fragment 和 supportFragmentManager 设置为最终的。现在一切正常， map 的“后台模式”已关闭，如果您从后台返回到 FragmentA， map 将正常工作。
如果有人知道如何直接关闭 map fragment 中的“背景模式”，请告诉我，我很乐意听到。
关于java - Google Maps v2 MapFragment 在从后台返回时非常滞后，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27978188/