不兼容的类型：片段不能转换为NavigationDrawerFragment [英] Incompatible types: Fragment cannot be converted to NavigationDrawerFragment

问题描述

我已经在一个应用程序使用工作14 API，但我不得不降级到10 API应用程序有碎片和活性的片段，我已导入库和使用了 getFragmentSupportManager ，因为它是V4。不过，我有以下错误：

I've been working on an app using API 14, but I had to downgrade to API 10. the app has fragments and activity fragments, I have imported the libraries and used the getFragmentSupportManager because it is v4. However, I have following error:

我创建了抽屉布局，从一开始就API 10个片段一个虚拟应用程序，它在 MyActivity 文件的同一行，这是不是一个错误。这里是我的code：

I created a dummy app with Drawer layout and fragments with API 10 from the beginning, it had the same line in MyActivity file and it was not an error. Here is my code:

package az.test2;

import android.app.Activity;
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.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.view.Gravity;


public class MyActivity 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_my);

        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
        android.support.v4.app.FragmentManager lolo;

        FragmentManager FM = getSupportFragmentManager();
        FragAV fav = new FragAV();
        FragW fw = new FragW();

        switch (position){
            case 0:
                FM.beginTransaction()
                    .replace(R.id.container, fav).commit();
                break;
            case 1:
                FM.beginTransaction()
                    .replace(R.id.container, fw).commit();
                break;
            case 2: break;
        }


        //FM.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;
        }
    }

    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.my, 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 {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";

        /**
         * 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_my, container, false);
            return rootView;
        }

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

我做的一切我可以，但这个错误似乎是非常罕见的。任何帮助将是非常美联社preciated。

I did everything I could but this error seems to be very rare. any help would be much appreciated.

推荐答案

在使用支持包，您的片段应该扩展 android.support.v4.app.Fragment 和不是正规片段类。

When using the support pack, your fragments should extend android.support.v4.app.Fragment and not the regular Fragment class.

这篇关于不兼容的类型：片段不能转换为NavigationDrawerFragment的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！