java - 来自 Firebase 的纬度和经度坐标不正确，并且所有帖子的纬度和经度坐标均相同

Question

用户从 Firebase 检索特定帖子的位置总是返回相同的错误位置，而且始终是相同的位置。我已经尝试了此代码的各种替代方法，试图解决它，以便用户为其事件创建的保存到 GoogleMap 的特定位置返回，但所有帖子都保持相同的位置，这是不正确的。

我在这里使用了一些其他有位置问题的帖子，但没有帮助我。

请告诉我我做错了什么。

Firebase

MapActivityUser.java

public class MapsActivityUser extends FragmentActivity implements OnMapReadyCallback {

    private GoogleMap map;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps_user);

        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        map = googleMap;

        DatabaseReference reference = FirebaseDatabase.getInstance().getReference("Posts");
        reference.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
                    if (snapshot.hasChild("location")) {
                        Post post = snapshot.getValue(Post.class);
                        double latitude = post.getLatitude();
                        double longitude = post.getLongitude();

                        LatLng location = new LatLng(latitude, longitude);
                        map.addMarker(new MarkerOptions().position(location).title("Event location"));
                        map.moveCamera(CameraUpdateFactory.newLatLngZoom(location, 10));
                    }
                }
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {

            }
        });
    }
}

PostActivity.java

    package com.e.events.Model;

public class Post {

    private String postid;
    private String postimage;
    private String description;
    private String publisher;
    private String text_event;
    private String text_location;
    private String text_date_time;
    private Long timestamp;
    private MyLocation location;

    public Post(String description, String postId, String postImage, String publisher, Long timestamp,
                String text_event, String text_location, String text_date_time, MyLocation location) {
        this.postid = postid;
        this.postimage = postimage;
        this.description = description;
        this.publisher = publisher;
        this.text_event = text_event;
        this.text_location = text_location;
        this.text_date_time = text_date_time;
        this.timestamp = timestamp;
        this.location = location;
    }

    public class MyLocation {

        private double latitude;
        private double longitude;
    }

    public Post() {
    }

    public String getPostid() {
        return postid;
    }

    public void setPostid(String postid) {
        this.postid = postid;
    }

    public String getPostimage() {
        return postimage;
    }

    public void setPostimage(String postimage) {
        this.postimage = postimage;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getPublisher() {
        return publisher;
    }

    public void setPublisher(String publisher) {
        this.publisher = publisher;
    }

    public String getText_event() {
        return text_event;
    }

    public void setText_event(String text_event) {
        this.text_event = text_event;
    }

    public String getText_location() {
        return text_location;
    }

    public void setText_location(String text_location) {
        this.text_location = text_location;
    }

    public String getText_date_time() {
        return text_date_time;
    }

    public void setText_date_time(String text_date_time) {
        this.text_date_time = text_date_time;
    }

    public Long getTimestamp() {
        return timestamp;
    }

    public void setTimestamp(Long timestamp) {
        this.timestamp = timestamp;
    }

    public MyLocation getLocation() {
        return location;
    }

    public void setLocation(MyLocation location) {
        this.location = location;
    }
}

Answer 1

您没有正确设置模型。更新您的帖子，如下所示:

Post.java:

public class Post {

    private String postid;
    private String postimage;
    private String description;
    private String publisher;
    private String text_event;
    private String text_location;
    private String text_date_time;
    private Long timestamp;
    private MyLocation location;

    //getter-setter

}

MyLocation.java:

public class MyLocation {

    private double latitude;
    private double longitude;


    public double getLatitude() {
        return latitude;
    }

    public void setLatitude(double latitude) {
        this.latitude = latitude;
    }

    public double getLongitude() {
        return longitude;
    }

    public void setLongitude(double longitude) {
        this.longitude = longitude;
    }
}

然后像这样解析

Post post = snapshot.getValue(Post.class);
double latitude = post.getLocation().getLatitude();
double longitude = post.getLocation().getLongitude();