Question

我一直收到以下错误：＆＃34;无法从Fragment转换为MapFragment＆＃34;

我已经在网上阅读了所有可能的帮助，而且我已经在这里工作了几个小时。

这是我的fragment_main.xml文件

<RelativeLayout 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.company.app.MainActivity$PlaceholderFragment">

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

</RelativeLayout>

这是我的MainActivity.java

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.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;

import android.app.Activity;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.*;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.DrawerLayout;
import android.widget.TextView;

public class MainActivity extends ActionBarActivity implements
        NavigationDrawerFragment.NavigationDrawerCallbacks {

    /**
     * Fragment managing the behaviors, interactions and presentation of the
     * navigation drawer.
     */
    private NavigationDrawerFragment mNavigationDrawerFragment;

    /**
     * Used to store the last screen title. For use in
     * {@link #restoreActionBar()}.
     */
    private CharSequence mTitle;

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

        mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager()
                .findFragmentById(R.id.navigation_drawer);
        mTitle = getTitle();

        // Set up the drawer.
        mNavigationDrawerFragment.setUp(R.id.navigation_drawer,
                (DrawerLayout) findViewById(R.id.drawer_layout));
    }

    @Override
    public void onNavigationDrawerItemSelected(int position) {
        // update the main content by replacing fragments
        FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentManager
                .beginTransaction()
                .replace(R.id.container,
                        PlaceholderFragment.newInstance(position + 1)).commit();
    }

    public void onSectionAttached(int number) {
        switch (number) {
        case 1:
            mTitle = getString(R.string.title_section1);
            break;
        case 2:
            mTitle = getString(R.string.title_section2);
            break;
        case 3:
            mTitle = getString(R.string.title_section3);
            break;
        case 4:
            mTitle = getString(R.string.title_section4);
            break;
        case 5:
            mTitle = getString(R.string.title_section5);
            break;
        }
    }

    public void restoreActionBar() {
        ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
        actionBar.setDisplayShowTitleEnabled(true);
        actionBar.setTitle(mTitle);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        if (!mNavigationDrawerFragment.isDrawerOpen()) {
            // Only show items in the action bar relevant to this screen
            // if the drawer is not showing. Otherwise, let the drawer
            // decide what to show in the action bar.
            getMenuInflater().inflate(R.menu.main, menu);
            restoreActionBar();
            return true;
        }
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment implements OnMapClickListener {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";
        GoogleMap map;

        /**
         * Returns a new instance of this fragment for the given section number.
         */
        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        public PlaceholderFragment() {
        }

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

            return rootView;
        }

        @Override
        public void onAttach(Activity activity) {
            super.onAttach(activity);
            ((MainActivity) activity).onSectionAttached(getArguments().getInt(
                    ARG_SECTION_NUMBER));
        }

        @Override
        public void onMapClick(LatLng arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onResume() {
            super.onResume();
            map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
        }

        @Override
        public void onStart() {
            super.onStart();
            map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
        }
    }
}

Answer 1

你们俩都有：

import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.SupportMapFragment;

尝试仅导入SupportMapFragment

Answer 2

如果您使用Activity将其更改为FragmentActivity

Answer 3

此答案最初包含在问题中。我已经将其移至此处，以符合站点标准，尽管我没有写答案。

我修复了我更改的问题

map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();

到

map = ((SupportMapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();

我实在不知所措，以至于我忘了更换演员表！

android map api无法从Fragment转换为MapFragment

3 个答案:

此答案最初包含在问题中。我已经将其移至此处，以符合站点标准，尽管我没有写答案。