我有一个带有三个选项卡的应用程序。

每个选项卡都有自己的布局.xml文件。xml有自己的映射片段。它是应用程序第一次启动时显示的那个。

一切都很好,除了当我在制表符之间改变。如果我尝试切换回地图片段选项卡,我会得到这个错误。在其他选项卡之间切换就可以了。

这里会出什么问题呢?

这是我的主类和main.xml,以及我使用的相关类(您还将在底部找到错误日志)

主类

package com.nfc.demo;

import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.widget.Toast;

public class NFCDemoActivity extends Activity {

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        ActionBar bar = getActionBar();
        bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        bar.setDisplayOptions(0, ActionBar.DISPLAY_SHOW_TITLE);

        bar.addTab(bar
                .newTab()
                .setText("Map")
                .setTabListener(
                        new TabListener<MapFragment>(this, "map",
                                MapFragment.class)));
        bar.addTab(bar
                .newTab()
                .setText("Settings")
                .setTabListener(
                        new TabListener<SettingsFragment>(this, "settings",
                                SettingsFragment.class)));
        bar.addTab(bar
                .newTab()
                .setText("About")
                .setTabListener(
                        new TabListener<AboutFragment>(this, "about",
                                AboutFragment.class)));

        if (savedInstanceState != null) {
            bar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0));
        }
        // setContentView(R.layout.main);

    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putInt("tab", getActionBar().getSelectedNavigationIndex());
    }

    public static class TabListener<T extends Fragment> implements
            ActionBar.TabListener {
        private final Activity mActivity;
        private final String mTag;
        private final Class<T> mClass;
        private final Bundle mArgs;
        private Fragment mFragment;

        public TabListener(Activity activity, String tag, Class<T> clz) {
            this(activity, tag, clz, null);
        }

        public TabListener(Activity activity, String tag, Class<T> clz,
                Bundle args) {
            mActivity = activity;
            mTag = tag;
            mClass = clz;
            mArgs = args;

            // Check to see if we already have a fragment for this tab,
            // probably from a previously saved state. If so, deactivate
            // it, because our initial state is that a tab isn't shown.
            mFragment = mActivity.getFragmentManager().findFragmentByTag(mTag);
            if (mFragment != null && !mFragment.isDetached()) {
                FragmentTransaction ft = mActivity.getFragmentManager()
                        .beginTransaction();
                ft.detach(mFragment);
                ft.commit();
            }
        }

        public void onTabSelected(Tab tab, FragmentTransaction ft) {
            if (mFragment == null) {
                mFragment = Fragment.instantiate(mActivity, mClass.getName(),
                        mArgs);
                ft.add(android.R.id.content, mFragment, mTag);
            } else {
                ft.attach(mFragment);
            }
        }

        public void onTabUnselected(Tab tab, FragmentTransaction ft) {
            if (mFragment != null) {
                ft.detach(mFragment);
            }
        }

        public void onTabReselected(Tab tab, FragmentTransaction ft) {
            Toast.makeText(mActivity, "Reselected!", Toast.LENGTH_SHORT)
                         .show();
        }
    }

}

main。xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <fragment
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/mapFragment"
        android:name="com.google.android.gms.maps.MapFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</LinearLayout>

相关类:MapFragment.java

package com.nfc.demo;

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class MapFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        super.onCreateView(inflater, container, savedInstanceState);
        return inflater.inflate(R.layout.main, container, false);
    }

    public void onDestroy() {
        super.onDestroy();
    }
}

错误

android.view.InflateException: Binary XML file line #7: 
     Error inflating class fragment
   at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
   at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
   at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
   at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
   at com.nfc.demo.MapFragment.onCreateView(MapFragment.java:15)
   at android.app.Fragment.performCreateView(Fragment.java:1695)
   at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885)
   at android.app.FragmentManagerImpl.attachFragment(FragmentManager.java:1255)
   at android.app.BackStackRecord.run(BackStackRecord.java:672)
   at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435)
   at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441)
   at android.os.Handler.handleCallback(Handler.java:725)
   at android.os.Handler.dispatchMessage(Handler.java:92)
   at android.os.Looper.loop(Looper.java:137)
   at android.app.ActivityThread.main(ActivityThread.java:5039)
   at java.lang.reflect.Method.invokeNative(Native Method)
   at java.lang.reflect.Method.invoke(Method.java:511)
   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
   at dalvik.system.NativeStart.main(Native Method)

Caused by: java.lang.IllegalArgumentException: 
     Binary XML file line #7: Duplicate id 0x7f040005, tag null, or 
     parent id 0xffffffff with another fragment for 
     com.google.android.gms.maps.MapFragment
   at android.app.Activity.onCreateView(Activity.java:4722)
   at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:680)
   ... 19 more

当前回答

As mentioned by @Justin Breitfeller, @Vidar Wahlberg solution is a hack which might not work in future version of Android. @Vidar Wahlberg perfer a hack because other solution might "cause the map to be recreated and redrawn, which isn't always desirable". Map redraw could be prevented by maintaining the old map fragment, rather than creating a new instance every time. @Matt solution doesn't work for me (IllegalStateException) As quoted by @Justin Breitfeller, "You cannot inflate a layout into a fragment when that layout includes a . Nested fragments are only supported when added to a fragment dynamically."

我的解决方案:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,                              Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_map_list, container, false);

    // init
    //mapFragment = (SupportMapFragment)getChildFragmentManager().findFragmentById(R.id.map);
    // don't recreate fragment everytime ensure last map location/state are maintain
    if (mapFragment == null) {
        mapFragment = SupportMapFragment.newInstance();
        mapFragment.getMapAsync(this);
    }
    FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
    // R.id.map is a layout
    transaction.replace(R.id.map, mapFragment).commit();

    return view;
}

其他回答

嵌套片段目前不受支持。 试试Support Package,修订版11。

这里需要注意的是,你的应用程序在两种情况下都会严重崩溃:-

1) In order to reuse fragment with Maps again MapView Fragment must be removed when your fragment showing Maps got replaced with other fragment in onDestroyView callback. else when you try to inflate same fragment twice Duplicate ID, tag null, or parent id with another fragment for com.google.android.gms.maps.MapFragment error will happen. 2) Secondly you must not mix app.Fragment operations with android.support.v4.app.Fragment API operations eg.do not use android.app.FragmentTransaction to remove v4.app.Fragment type MapView Fragment. Mixing this will again result into crash from fragment side.

下面是正确使用MapView的示例代码片段

import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnMapClickListener;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.serveroverload.yago.R;

/**
 * @author 663918
 *
 */
public class HomeFragment extends Fragment implements LocationListener {
    // Class to do operations on the Map
    GoogleMap googleMap;
    private LocationManager locationManager;

    public static Fragment newInstance() {
        return new HomeFragment();
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.home_fragment, container, false);
        Bundle bdl = getArguments();

        // setuping locatiomanager to perfrom location related operations
        locationManager = (LocationManager) getActivity().getSystemService(
                Context.LOCATION_SERVICE);

        // Requesting locationmanager for location updates
        locationManager.requestLocationUpdates(
                LocationManager.NETWORK_PROVIDER, 1, 1, this);

        // To get map from MapFragment from layout
        googleMap = ((MapFragment) getActivity().getFragmentManager()
                .findFragmentById(R.id.map)).getMap();

        // To change the map type to Satellite
        // googleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);

        // To show our current location in the map with dot
        // googleMap.setMyLocationEnabled(true);

        // To listen action whenever we click on the map
        googleMap.setOnMapClickListener(new OnMapClickListener() {

            @Override
            public void onMapClick(LatLng latLng) {
                /*
                 * LatLng:Class will give us selected position lattigude and
                 * longitude values
                 */
                Toast.makeText(getActivity(), latLng.toString(),
                        Toast.LENGTH_LONG).show();
            }
        });

        changeMapMode(2);

        // googleMap.setSatellite(true);
        googleMap.setTrafficEnabled(true);
        googleMap.setBuildingsEnabled(true);
        googleMap.setMyLocationEnabled(true);

        return v;
    }

    private void doZoom() {
        if (googleMap != null) {
            googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
                    new LatLng(18.520430, 73.856744), 17));
        }
    }

    private void changeMapMode(int mapMode) {

        if (googleMap != null) {
            switch (mapMode) {
            case 0:
                googleMap.setMapType(GoogleMap.MAP_TYPE_NONE);
                break;

            case 1:
                googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
                break;

            case 2:
                googleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
                break;

            case 3:
                googleMap.setMapType(GoogleMap.MAP_TYPE_TERRAIN);
                break;

            case 4:
                googleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
                break;

            default:
                break;
            }
        }
    }

    private void createMarker(double latitude, double longitude) {
        // double latitude = 17.385044;
        // double longitude = 78.486671;

        // lets place some 10 random markers
        for (int i = 0; i < 10; i++) {
            // random latitude and logitude
            double[] randomLocation = createRandLocation(latitude, longitude);

            // Adding a marker
            MarkerOptions marker = new MarkerOptions().position(
                    new LatLng(randomLocation[0], randomLocation[1])).title(
                    "Hello Maps " + i);

            Log.e("Random", "> " + randomLocation[0] + ", " + randomLocation[1]);

            // changing marker color
            if (i == 0)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_AZURE));
            if (i == 1)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_BLUE));
            if (i == 2)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_CYAN));
            if (i == 3)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
            if (i == 4)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
            if (i == 5)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_ORANGE));
            if (i == 6)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_RED));
            if (i == 7)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_ROSE));
            if (i == 8)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_VIOLET));
            if (i == 9)
                marker.icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_YELLOW));

            googleMap.addMarker(marker);

            // Move the camera to last position with a zoom level
            if (i == 9) {
                CameraPosition cameraPosition = new CameraPosition.Builder()
                        .target(new LatLng(randomLocation[0], randomLocation[1]))
                        .zoom(15).build();

                googleMap.animateCamera(CameraUpdateFactory
                        .newCameraPosition(cameraPosition));
            }
        }

    }

    /*
     * creating random postion around a location for testing purpose only
     */
    private double[] createRandLocation(double latitude, double longitude) {

        return new double[] { latitude + ((Math.random() - 0.5) / 500),
                longitude + ((Math.random() - 0.5) / 500),
                150 + ((Math.random() - 0.5) * 10) };
    }

    @Override
    public void onLocationChanged(Location location) {

        if (null != googleMap) {
            // To get lattitude value from location object
            double latti = location.getLatitude();
            // To get longitude value from location object
            double longi = location.getLongitude();

            // To hold lattitude and longitude values
            LatLng position = new LatLng(latti, longi);

            createMarker(latti, longi);

            // Creating object to pass our current location to the map
            MarkerOptions markerOptions = new MarkerOptions();
            // To store current location in the markeroptions object
            markerOptions.position(position);

            // Zooming to our current location with zoom level 17.0f
            googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(position,
                    17f));

            // adding markeroptions class object to the map to show our current
            // location in the map with help of default marker
            googleMap.addMarker(markerOptions);
        }

    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onProviderEnabled(String provider) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onProviderDisabled(String provider) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onDestroyView() {
        // TODO Auto-generated method stub
        super.onDestroyView();

        locationManager.removeUpdates(this);

        android.app.Fragment fragment = getActivity().getFragmentManager()
                .findFragmentById(R.id.map);
        if (null != fragment) {
            android.app.FragmentTransaction ft = getActivity()
                    .getFragmentManager().beginTransaction();
            ft.remove(fragment);
            ft.commit();
        }
    }

}

XML

 <fragment
        android:id="@+id/map"
        android:name="com.google.android.gms.maps.MapFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
       />

结果如下所示:-

希望它能帮助到某人。

问题是你试图做的事情不应该被做。你不应该让碎片在其他碎片中膨胀。来自Android的文档:

注意:不能在布局时将布局膨胀为片段 包含<fragment>。只有在添加时才支持嵌套片段 动态地连接到一个片段。

虽然您可以使用这里提供的技巧来完成任务,但我强烈建议您不要这样做。当你试图为包含另一个片段的片段膨胀布局时,不可能确定这些黑客将处理每个新的Android操作系统。

android支持的将一个片段添加到另一个片段的唯一方法是通过来自子片段管理器的事务。

简单地将XML布局更改为空容器(如果需要添加ID):

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/mapFragmentContainer"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
</LinearLayout>

然后在Fragment onViewCreated(View View, @Nullable Bundle savedInstanceState)方法中:

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    FragmentManager fm = getChildFragmentManager();
    SupportMapFragment mapFragment = (SupportMapFragment) fm.findFragmentByTag("mapFragment");
    if (mapFragment == null) {
        mapFragment = new SupportMapFragment();
        FragmentTransaction ft = fm.beginTransaction();
        ft.add(R.id.mapFragmentContainer, mapFragment, "mapFragment");
        ft.commit();
        fm.executePendingTransactions();
    }
    mapFragment.getMapAsync(callback);
}

我建议替换()而不是attach()/detach()在你的标签处理。

或者,切换到ViewPager。下面是一个示例项目,展示了一个ViewPager,带有选项卡,托管10个地图。

我尊重所有的答案,但我发现了一个简单的解决方案: 如果n是标签的数量,则:

 mViewPager.setOffscreenPageLimit(n);

例子: 如有提及:

 mViewPager.setOffscreenPageLimit(2);

viewpager实现了一个队列,所以你不必让它删除那个片段。onCreateView只被调用一次。