Question

我正在尝试确定处理多个地图的最佳方式。我应该在单个地图中添加和删除内容，还是在两个地图片段之间切换。理想情况下，我认为使用片段会更好，因为我可以轻松使用后退按钮。

当我尝试在buttonclick上显示（）和隐藏（）多个地图片段时出现问题。使用show（）/ hide（）不会更改地图。也许有人可以为我解释为什么会发生这种情况，这样我就可以更好地了解显示和隐藏的地图视图的实际情况。有人在显示和隐藏地图片段方面有任何问题吗？

当我点击按钮时，mapview不会改变，但我失去控制，除非我再次点击该按钮。似乎片段正在切换，但实际上并没有改变它的视图。我确信使用replace（）可以正常工作，但这会破坏加载地图的目的。

package com.test.googletestmaps;
public class ControlFragment extends SherlockFragmentActivity implements
    OnClickListener {

private GoogleMap mMap;
private GoogleMap mMap2;
private SupportMapFragment gmap;
private SupportMapFragment gmap2;
private ImageButton button;
private int mapShown;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_control_fragment);
    gmap = ((SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map1));
    gmap2 = ((SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map2));

    if (savedInstanceState == null) {
        // First incarnation of this activity.
        gmap.setRetainInstance(true);
    } else {
        // Reincarnated activity. The obtained map is the same map instance
        // in the previous
        // activity life cycle. There is no need to reinitialize it.
        mMap = gmap.getMap();
    }
    if (savedInstanceState == null) {
        // First incarnation of this activity.
        gmap2.setRetainInstance(true);
    } else {
        // Reincarnated activity. The obtained map is the same map instance
        // in the previous
        // activity life cycle. There is no need to reinitialize it.
        mMap2 = gmap2.getMap();
    }
    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    ft.hide(gmap2);
    ft.commit();
    button = ((ImageButton) findViewById(R.id.cacbutton));
    button.setOnClickListener(this);
    button.setVisibility(View.VISIBLE);
    mapShown = 0;
    setUpMapIfNeeded();
}

@Override
protected void onResume() {
    super.onResume();
    setUpMapIfNeeded();
}

private void setUpMapIfNeeded() {
    // Do a null check to confirm that we have not already instantiated the
    // map.
    if (mMap == null) {
        // Try to obtain the map from the SupportMapFragment.
        mMap = ((SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map1)).getMap();
        // Check if we were successful in obtaining the map.
        if (mMap != null) {
            setUpMap(0);
        }

    }
    if (mMap2 == null) {
        mMap2 = ((SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map2)).getMap();

        if (mMap2 != null) {
            setUpMap(1);
        }
    }
}

private void setUpMap(int mapNumber) {
    switch (mapNumber) {
    case 0:
        mMap.getUiSettings().setZoomControlsEnabled(true);
        mMap.addMarker(new MarkerOptions().position(new LatLng(5, 5)).title("Marker for map1"));
        break;
    case 1:
        mMap2.getUiSettings().setZoomControlsEnabled(true);
        mMap2.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker for map2"));
        break;
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu with the options to show the Map and the ListView.
    getSupportMenuInflater()
            .inflate(R.menu.activity_control_fragment, menu);
    return true;
}

@Override
public void onClick(View v) {
    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    ft.setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out);
    if (mapShown == 0)
    {
        ft.hide(gmap);
        ft.show(gmap2);
        mapShown = 1;
    }
    else
    {
        ft.hide(gmap2);
        ft.show(gmap);
        mapShown = 0;

    }
    ft.addToBackStack(null);
    ft.commit();

}
}

编辑：我找到this链接，解释了如何显示和隐藏地图片段，我尝试使用getView().setVisibility()，但我得到了相同的结果。

编辑：这显然不是容易解决的问题。我环顾四周，我无法找到解决方案。现在我将使用添加/删除来控制我的片段。

这仍然没有解决....我采取了不同的路线。显示/隐藏片段不适用于新谷歌地图片段的多个实例。我不确定为什么，如果有人找到解决方案或理由，请发布并分享。

Answer 1

面对这个问题，在搜索解决方案后，我找到了一些有用的链接：

Initialize MapFragment programmatically with Maps API v2

Multiple Map fragment in action bar tab

Multiple maps v2 in TabActivity

https://stackoverflow.com/questions/15654321/multiple-map-fragment-in-android-app

Issue while using 2 map fragments in One application

Only first map is showing with Multiple SupportMapFragment in ViewPager

Performance of multiple MapFragments (Android Map API v2)

但我决定以我的风格做这件事：

如果片段属于同一个Activity ，这就是我浏览多个地图片段的方式。如果mapfragments属于不同的Activity（我的意思是每mapfragment一个Activity），这个问题，至少在我的情况下，是由Android操作系统管理的，所以我不应该做任何特别的事。

case 1: if(getActivity().getSupportFragmentManager().findFragmentById(R.id.map_fragment1) == null){ if(getActivity().getSupportFragmentManager().findFragmentById(R.id.map_fragment2) != null){ FragmentManager manager = getActivity().getSupportFragmentManager(); FragmentTransaction ft = manager.beginTransaction(); ft.remove(getActivity().getSupportFragmentManager().findFragmentById(R.id.map_fragment2)); ft.commit(); } FragmentManager manager1 = getActivity().getSupportFragmentManager(); FragmentTransaction ft1 = manager1.beginTransaction(); ft1.replace(R.id.frame_mapView, new Map1Fragment()); ft1.commit(); } break; case 3: if(getActivity().getSupportFragmentManager().findFragmentById(R.id.map_fragment2) == null){ if(getActivity().getSupportFragmentManager().findFragmentById(R.id.map_fragment1) != null){ FragmentManager manager = getActivity().getSupportFragmentManager(); FragmentTransaction ft = manager.beginTransaction(); ft.remove(getActivity().getSupportFragmentManager().findFragmentById(R.id.map_fragment1)); ft.commit(); } FragmentManager manager1 = getActivity().getSupportFragmentManager(); FragmentTransaction ft1 = manager1.beginTransaction(); ft1.replace(R.id.frame_mapView, new Map2Fragment()); ft1.commit(); } break;

Map1Fragment和Map2Fragment，其中每个extends Fragment并且包含<fragment android:id="@+id/map_fragment1" class="com.google.android.gms.maps.SupportMapFragment" />的XML布局，但您可以只扩展SupportMapFragment，取决于你的需求。

多个地图的最佳实践

1 个答案: