Question

以下代码解析来自xml Web服务的数据，并应将所选项目的数据从列表视图传递到下一个活动。

代码运行良好，直到我点击列表项将数据传递到下一个活动，然后应用程序崩溃。

我已经尝试了许多修复来解决问题，比如删除setcontentView但仍然相同。

 public class LastActivity extends ListActivity {
        /** Called when the activity is first created. */
        ListView lv;

    static String UName="name";
    static String UniUrl="description";
    public String val;
    static List<String> links;
    static List<String> names;



    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        lv=(ListView) findViewById(R.id.list1);
        links=new ArrayList<String>();
        names=new ArrayList<String>();
        try{

            URL url=new URL("http://api.androidhive.info/pizza/?format=xml");
            XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
            factory.setNamespaceAware(false);
            XmlPullParser xpp = factory.newPullParser();
            xpp.setInput(getInputStream(url), "UTF_8");
            boolean insideItem = false;


                    // Returns the type of current event: START_TAG, END_TAG, etc..

            int eventType = xpp.getEventType();

            while (eventType != XmlPullParser.END_DOCUMENT) {

                    if (eventType == XmlPullParser.START_TAG) {


                        if (xpp.getName().equalsIgnoreCase("item")) {

                            insideItem = true;

                        } else if (xpp.getName().equalsIgnoreCase(UName)) {

                            if (insideItem)

                                names.add(xpp.nextText()); //extract the headline
                               // val=xpp.nextText();
                        } else if (xpp.getName().equalsIgnoreCase(UniUrl)) {

                            if (insideItem)

                                links.add(xpp.nextText()); //extract the link of article

                        }
                    }else if(eventType==XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")){

                        insideItem=false;

                    }

                    eventType = xpp.next(); //move to next element

                }


        }catch (MalformedURLException e) {

            e.printStackTrace();

        } catch (XmlPullParserException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }catch (Exception e)
        {
            e.printStackTrace();

        }
        /*ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, names);

                setListAdapter(adapter);*/
                 lv = getListView();
                   ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                            android.R.layout.simple_list_item_1, names);
                    setListAdapter(adapter); 



                    lv.setOnItemClickListener(new OnItemClickListener(){
                        public void onItemClick(AdapterView<?> parent, View view,
                        int position, long id)
                        {

                               String bb=parent.getItemAtPosition(position).toString();
                               Intent i = new Intent(getApplicationContext(), Details.class);
                               //  String x=edt.getText().toString();
                                i.putExtra("name",bb);
                                // starting new activity
                                startActivity(i);

                        }
                    });
            }


    private InputStream getInputStream(URL url) {
        // TODO Auto-generated method stub
        try {
             return url.openConnection().getInputStream();
             } catch (IOException e) {
                   return null;
            }

    }

}


//detail activity:

    public class Details extends LastActivity{
        LastActivity last=new LastActivity();
        TextView tv;
        TextView url;
        String read;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            super.onCreate(savedInstanceState);
            setContentView(R.layout.details);

            tv=(TextView) findViewById(R.id.text);
            //url=(TextView) findViewById(R.id.link);
            Intent intent=getIntent();

                // receiving  data
                String name = intent.getStringExtra("name");
               //String path=intent.getStringExtra("url");

                //Log.e("Second Screen", name + ".");
                //tv.setText(name);
               // url.setText(path);
        }
    }

Answer 1

在详细信息活动中扩展Activity而不是LastActivity

public class Details extends Activity{
        //LastActivity last=new LastActivity();
       .....

从listView中的活动之间传递数据

1 个答案: