java - fragment mDrawer 菜单

Question

我正在构建一个带有 mDrawer 菜单的简单 webview 应用程序，它在 3.0+ android 上工作就像一个魅力，但我希望它能够与 3 以下的版本一起工作。我已经阅读了有关 v4 支持的信息，并将其添加到项目中。应用程序是一个 Activity，然后我更改为 FragmentActivity，因为关闭了支持库。对不起我的英语。

这是代码。

public class MainActivity extends FragmentActivity  {
     private LayoutInflater mInflater;
     private DrawerLayout mDrawerLayout;
     WebView browser;
     // ListView represents Navigation Drawer
     private ListView mDrawerList;

     // ActionBarDrawerToggle indicates the presence of Navigation Drawer in the action bar
     private ActionBarDrawerToggle mDrawerToggle;
     private String mTitle = "";


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        WebView browser = (WebView) findViewById(R.id.webView1);
        browser.loadUrl("");
         browser.setWebViewClient(new WebViewClient());
         WebSettings webSettings = browser.getSettings();
         webSettings.setJavaScriptEnabled(true);

        mInflater = (LayoutInflater) getSystemService(Activity.LAYOUT_INFLATER_SERVICE);


        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);

        mDrawerList = (ListView) findViewById(R.id.drawer_list);

        // Getting reference to the ActionBarDrawerToggle
        mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
                        R.drawable.ic_drawer, R.string.drawer_open,
                        R.string.drawer_close) {

                /** Called when drawer is closed */
                public void onDrawerClosed(View view) {
                        getActionBar().setTitle(mTitle);

                        invalidateOptionsMenu();

                }

                /** Called when a drawer is opened */
                public void onDrawerOpened(View drawerView) {
                    getActionBar().setTitle("Menu");

                        invalidateOptionsMenu();
                }


        };
        browser.setOnKeyListener(new OnKeyListener()
        {
            public boolean onKey(View v, int keyCode, KeyEvent event)
            {
                if(event.getAction() == KeyEvent.ACTION_DOWN)
                {
                    WebView webView = (WebView) v;

                    switch(keyCode)
                    {
                        case KeyEvent.KEYCODE_BACK:
                            if(webView.canGoBack())
                            {
                                webView.goBack();
                                return true;
                            }
                            break;
                    }
                }

                return false;
            }
        });

        // Setting DrawerToggle on DrawerLayout
        mDrawerLayout.setDrawerListener(mDrawerToggle);

        // Creating an ArrayAdapter to add items to the listview mDrawerList
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(getBaseContext(),
                        R.layout.drawer_list_item, getResources().getStringArray(R.array.menus));

        // Setting the adapter on mDrawerList
        mDrawerList.setAdapter(adapter);

        // Enabling Home button
        getActionBar().setHomeButtonEnabled(true);

        // Enabling Up navigation
        getActionBar().setDisplayHomeAsUpEnabled(true);

        // Setting item click listener for the listview mDrawerList
        mDrawerList.setOnItemClickListener(new OnItemClickListener() {

                @Override
                public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {

                        // Getting an array of rivers
                        String[] menuItems = getResources().getStringArray(R.array.menus);

                        // Currently selected river
                        mTitle = menuItems[position];

                        // Creating a fragment object


                        // Passing selected item information to fragment
                        Bundle data = new Bundle();
                        data.putInt("position", position);
                        data.putString("url", getUrl(position));



                        // Getting reference to the FragmentManager
                        FragmentManager fragmentManager = getSupportFragmentManager();

                        fragmentManager.addOnBackStackChangedListener(new OnBackStackChangedListener() {
                            public void onBackStackChanged() {
                                if(getFragmentManager().getBackStackEntryCount() == 0) finish();
                            }
                        });

                        // Creating a fragment transaction
                        FragmentTransaction ft = fragmentManager.beginTransaction();

                        // Adding a fragment to the fragment transaction


                        // Committing the transaction
                        ft.commit();

                        // Closing the drawer
                        mDrawerLayout.closeDrawer(mDrawerList);

                }
        });     


    }

问题出在

fragmentManager.addOnBackStackChangedListener(new OnBackStackChangedListener() {
                            public void onBackStackChanged() {
                                if(getFragmentManager().getBackStackEntryCount() == 0) finish();
                            }
                        });

FragmentManager 类型中的方法 addOnBackStackChangedListener(FragmentManager.OnBackStackChangedListener) 不适用于参数 (new FragmentManager.OnBackStackChangedListener(){})

Answer 1

您导入了错误的FragmentManager.OnBackStackChangedListener。

你拥有什么

import android.app.FragmentManager.OnBackStackChangedListener;

你应该拥有什么

import android.support.v4.app.FragmentManager.OnBackStackChangedListener;