我正在构建一个与谷歌地图相关的应用程序。在这我想尝试在片段中实现地图。我在OnMapReady方法中操作地图。但是app并没有调用OnMapReady方法。我在活动中实现了同样的东西,并且它的工作完美。但它没有片段化。我不知道它是否存在碎片生命周期的问题而我错过了什么。 这是代码。
Maps_Fragment.java
package com.example.mudasir.login;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.LatLngBounds;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import java.io.IOException;
import java.util.List;
/**
* A simple {@link Fragment} subclass.
*/
public class Maps_Fragment extends Fragment implements OnMapReadyCallback {
public GoogleMap mMap;
String[] showroom_addresses = new String[5];
List<Address> addressList = null;
LatLng latlng;
LatLngBounds.Builder builder = new LatLngBounds.Builder();
View view1;
public Maps_Fragment() {
// Required empty public constructor
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_maps_, container, false);
}
@Override
public void onViewCreated(View view,Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
SupportMapFragment mapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.maps);
mapFragment.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
showroom_addresses[0] = "Dubai";
showroom_addresses[1] = "Fujairah";
showroom_addresses[2] = "Al Ain";
showroom_addresses[3] = "Sharjah";
showroom_addresses[4] = "Ras Al Khaimah";
Geocoder geocoder = new Geocoder(getActivity());
for(int i =0; i<5; i++) {
try {
addressList = geocoder.getFromLocationName(showroom_addresses[i], 1);
} catch (IOException e) {
e.printStackTrace();
}
android.location.Address address = addressList.get(0);
latlng = new LatLng(address.getLatitude(), address.getLongitude());
Marker marker = googleMap.addMarker(new MarkerOptions().position(latlng).title(showroom_addresses[i]));
builder.include(marker.getPosition());
}
LatLngBounds bounds = builder.build();
int padding = 0;
CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds,padding);
//CameraUpdate cu = CameraUpdateFactory.newLatLngZoom(new MarkerOptions().position(latlng).title(showroom_addresses[3]).getPosition(),7F);
googleMap.animateCamera(cu);
}
}
Maps_Fragment.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.mudasir.login.Maps_Fragment">
<!-- TODO: Update blank fragment layout -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/linearLayout">
<fragment android:id="@+id/maps"
android:layout_width="wrap_content"
android:layout_height="match_parent"
class="com.google.android.gms.maps.MapFragment"
android:layout_alignParentTop="true">
</fragment>
相同的方法和要求在活动的情况下工作正常,但在片段的情况下它的错误。请帮助。
答案 0 :(得分:4)
您必须从
延伸SupportMapFragment
而不是
Fragment
<强> [EDITED] 强>
我的建议是有2个片段:一个没有任何结果,另一个带有SupportFragmentManager。
此外,在应该从SupportFragmentManager扩展的Maps_Fragment中,您必须删除onCreateView和onViewCreated的覆盖,否则您应该管理所有的SupportMapFragment,我认为您不想这样做。
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_maps_, container, false);
}
@Override
public void onViewCreated(View view,Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
SupportMapFragment mapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.maps);
mapFragment.getMapAsync(this);
}]
要实现OnMapReadyCallback,我将在onActivityCreated方法中执行:
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
getMapAsync(this);
}
答案 1 :(得分:0)
实现此方法的更好方法是使用MapView而不是MapFragment。并做下面的事情
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.mudasir.login.Maps_Fragment">
<!-- TODO: Update blank fragment layout -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/linearLayout">
<com.google.android.gms.maps.MapView
android:id="@+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>
</FrameLayout>
您的Maps_Fragment.java类
public class Maps_Fragment extends Fragment implements OnMapReadyCallback {
private View view;
private MapView mapView;
String[] showroom_addresses = new String[5];
List<Address> addressList = null;
LatLng latlng;
LatLngBounds.Builder builder = new LatLngBounds.Builder();
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_maps_, container, false);
// Gets the MapView from the XML layout and creates it
mapView = (MapView) view.findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
// Set the map ready callback to receive the GoogleMap object
mapView.getMapAsync(this);
return view;
}
@Override
public void onMapReady(GoogleMap googleMap) {
// Need to call MapsInitializer before doing any CameraUpdateFactory calls
try {
MapsInitializer.initialize(this.getActivity());
} catch (GooglePlayServicesNotAvailableException e) {
e.printStackTrace();
}
mGoogleMap = googleMap;
showroom_addresses[0] = "Dubai";
showroom_addresses[1] = "Fujairah";
showroom_addresses[2] = "Al Ain";
showroom_addresses[3] = "Sharjah";
showroom_addresses[4] = "Ras Al Khaimah";
Geocoder geocoder = new Geocoder(getActivity());
for(int i =0; i<5; i++) {
try {
addressList = geocoder.getFromLocationName(showroom_addresses[i], 1);
} catch (IOException e) {
e.printStackTrace();
}
android.location.Address address = addressList.get(0);
latlng = new LatLng(address.getLatitude(), address.getLongitude());
Marker marker = mGoogleMap.addMarker(new MarkerOptions().position(latlng).title(showroom_addresses[i]));
builder.include(marker.getPosition());
}
LatLngBounds bounds = builder.build();
int padding = 0;
CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds,padding);
//CameraUpdate cu = CameraUpdateFactory.newLatLngZoom(new MarkerOptions().position(latlng).title(showroom_addresses[3]).getPosition(),7F);
mGoogleMap.animateCamera(cu);
}
@Override
public void onResume() {
mapView.onResume();
super.onResume();
}
@Override
public void onDestroyView() {
super.onDestroy();
mapView.onDestroy();
}
}
请确保您有片段和地图的以下导入
import android.support.v4.app.Fragment;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapView;
import com.google.android.gms.maps.MapsInitializer;
import com.google.android.gms.maps.OnMapReadyCallback;