1

タブフラグメントに何も表示されないようです。私のコードには何かが欠けているに違いないことを私は知っています。誰か助けてくれませんか？以下は私の試みです。

UgglyNoodleによる提案後に変更

問題：フラグメントタブに何も表示されません。

MainActivity.java

  public class MainActivity extends SherlockFragmentActivity implements TabListener {
    private Fragment mFragment;

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

        setContentView(R.layout.main);

        ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        actionBar.setDisplayShowTitleEnabled(true);

        //mFragment = new AppleFragment();

        Tab tab = actionBar.newTab()
                .setText("Apple")
                .setTabListener(this)
                .setIcon(R.drawable.apple);

        actionBar.addTab(tab);


    }

    @Override
    public void onTabSelected(Tab tab, FragmentTransaction ft) {
         if (mFragment == null) {
                mFragment = new AppleFragment();
                ft.add(android.R.id.content, mFragment);
            } else {
                ft.attach(mFragment);
            }
    }

    @Override
    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
        ft.detach(mFragment);
    }

    @Override
    public void onTabReselected(Tab tab, FragmentTransaction ft) {
    }
}

AppleFragment.java 

    public class AppleFragment extends SherlockListFragment{


        static final String URL = "http://api.androidhive.info/pizza/?format=xml";
        // XML node keys
        static final String KEY_ITEM = "item"; // parent node
        static final String KEY_ID = "id";
        static final String KEY_NAME = "name";
        static final String KEY_COST = "cost";
        static final String KEY_DESC = "description";



        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){

        return super.onCreateView(inflater, container, savedInstanceState);

        }


        public void onActivityCreated(Bundle savedInstanceState) {

            ArrayList<HashMap<String, String>> menuItems = new ArrayList<HashMap<String, String>>();


            XMLParser parser = new XMLParser();
            String xml = parser.getXmlFromUrl(URL); // getting XML
            Document doc = parser.getDomElement(xml); // getting DOM element

            NodeList nl = doc.getElementsByTagName(KEY_ITEM);
            // looping through all item nodes <item>
            for (int i = 0; i < nl.getLength(); i++) {
                // creating new HashMap
                HashMap<String, String> map = new HashMap<String, String>();
                Element e = (Element) nl.item(i);
                // adding each child node to HashMap key => value
                map.put(KEY_ID, parser.getValue(e, KEY_ID));
                map.put(KEY_NAME, parser.getValue(e, KEY_NAME));
                map.put(KEY_COST, "Rs." + parser.getValue(e, KEY_COST));
                map.put(KEY_DESC, parser.getValue(e, KEY_DESC));

                // adding HashList to ArrayList
                menuItems.add(map);
            }

            ListAdapter adapter = new SimpleAdapter(getActivity(), menuItems,
                    R.layout.list_item,
                    new String[] { KEY_NAME, KEY_DESC, KEY_COST }, new int[] {
                            R.id.name, R.id.desciption, R.id.cost });


            setListAdapter(adapter);    


        }
}

XMLParser.java

public class XMLParser {

    // constructor
    public XMLParser() {

    }

    /**
     * Getting XML from URL making HTTP request
     * @param url string
     * */
    public String getXmlFromUrl(String url) {
        String xml = null;

        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            xml = EntityUtils.toString(httpEntity);

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        // return XML
        return xml;
    }

    /**
     * Getting XML DOM element
     * @param XML string
     * */
    public Document getDomElement(String xml){
        Document doc = null;
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        try {

            DocumentBuilder db = dbf.newDocumentBuilder();

            InputSource is = new InputSource();
                is.setCharacterStream(new StringReader(xml));
                doc = db.parse(is); 

            } catch (ParserConfigurationException e) {
                Log.e("Error: ", e.getMessage());
                return null;
            } catch (SAXException e) {
                Log.e("Error: ", e.getMessage());
                return null;
            } catch (IOException e) {
                Log.e("Error: ", e.getMessage());
                return null;
            }

            return doc;
    }

    /** Getting node value
      * @param elem element
      */
     public final String getElementValue( Node elem ) {
         Node child;
         if( elem != null){
             if (elem.hasChildNodes()){
                 for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
                     if( child.getNodeType() == Node.TEXT_NODE  ){
                         return child.getNodeValue();
                     }
                 }
             }
         }
         return "";
     }

     /**
      * Getting node value
      * @param Element node
      * @param key string
      * */
     public String getValue(Element item, String str) {     
            NodeList n = item.getElementsByTagName(str);        
            return this.getElementValue(n.item(0));
        }
}

Logcat：

10-05 16:24:30.031: E/AndroidRuntime(19244): FATAL EXCEPTION: main
10-05 16:24:30.031: E/AndroidRuntime(19244): java.lang.RuntimeException: Unable to start activity ComponentInfo{in.wptrafficanalyzer.actionbarsherlocknavtab/in.wptrafficanalyzer.actionbarsherlocknavtab.MainActivity}: android.os.NetworkOnMainThreadException
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1970)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1995)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.ActivityThread.access$600(ActivityThread.java:127)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1161)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.os.Handler.dispatchMessage(Handler.java:99)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.os.Looper.loop(Looper.java:137)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.ActivityThread.main(ActivityThread.java:4512)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at java.lang.reflect.Method.invokeNative(Native Method)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at java.lang.reflect.Method.invoke(Method.java:511)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:982)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:749)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at dalvik.system.NativeStart.main(Native Method)
10-05 16:24:30.031: E/AndroidRuntime(19244): Caused by: android.os.NetworkOnMainThreadException
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at java.net.InetAddress.getAllByName(InetAddress.java:220)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at in.wptrafficanalyzer.actionbarsherlocknavtab.XMLParser.getXmlFromUrl(XMLParser.java:45)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at in.wptrafficanalyzer.actionbarsherlocknavtab.AppleFragment.onCreate(AppleFragment.java:50)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:834)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1080)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:622)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1416)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:505)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1136)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.Activity.performStart(Activity.java:4475)
10-05 16:24:30.031: E/AndroidRuntime(19244):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1943)
10-05 16:24:30.031: E/AndroidRuntime(19244):    ... 11 more
4

1 に答える 1

2

あなたのAppleFragmentクラスは必要ありません。代わりに、MainActivity実装する必要がありますTabListener。基本的なアイデアを提供する簡単なコードを次に示しますが、まだテストしていないため、修正が必要です。

public class MainActivity extends SherlockFragmentActivity implements TabListener {
    private Fragment mFragment;

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

        setContentView(R.layout.main);

        ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        actionBar.setDisplayShowTitleEnabled(true);

        Tab tab = actionBar.newTab()
                .setText("Apple")
                .setTabListener(this)
                .setIcon(R.drawable.apple);

        actionBar.addTab(tab);
    }

    @Override
    public void onTabSelected(Tab tab, FragmentTransaction ft) {
    if (mFragment == null) {
        mFragment = new ArrayListFragment();
        ft.add(R.id.content, mFragment, "some_tag");
    } else {
        ft.attach(mFragment);
    }

    @Override
    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
        ft.detach(mFragment);
    }

    @Override
    public void onTabReselected(Tab tab, FragmentTransaction ft) {
    }
}

複数のタブがある場合は、複数のフラグメントを追跡し、選択したタブに応じて適切なフラグメントをアタッチおよびデタッチする必要があります。

最後に、ArrayListFragment拡張する必要がListFragmentあり、引き続き使用できますsetListAdapter()。

このページにはかなり良い例がありますが、私が提案したものより少し複雑です。

于 2012-10-05T04:07:44.673 に答える