在实现滑动选项卡时执行doInBackground()时出错

时间:2014-04-22 17:01:05

标签: android android-asynctask google-places-api swipeview

我从here下载了用于实施Google Places API的源代码(可以从here下载),但它只有一个基本的ListView,但我想将swipable标签与它集成,所以我尝试了一切,最后,尝试将每个文件的每一行复制到一个新项目中,当以某种方式,在删除大量错误后,LogCat显示了这一点:

04-22 22:17:49.398: E/AndroidRuntime(12254): FATAL EXCEPTION: AsyncTask #1
04-22 22:17:49.398: E/AndroidRuntime(12254): java.lang.RuntimeException: An error occured while executing doInBackground()

MainActivty.java:

package project.mad.travelmate;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Locale;

import project.mad.travelmate.Place;

import project.mad.travelmate.MainActivity;
import project.mad.travelmate.PlacesMapActivity;
import project.mad.travelmate.R;
import project.mad.travelmate.SinglePlaceActivity;
import project.mad.travelmate.MainActivity.LoadPlaces;
import project.mad.travelmate.AlertDialogManager;
import project.mad.travelmate.ConnectionDetector;
import project.mad.travelmate.GPSTracker;
import project.mad.travelmate.GooglePlaces;
import project.mad.travelmate.PlacesList;
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.support.v4.app.FragmentTransaction;
import android.support.v4.app.FragmentPagerAdapter;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.text.Html;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;

public class MainActivity extends ActionBarActivity implements
        ActionBar.TabListener {

    SectionsPagerAdapter mSectionsPagerAdapter;

    ViewPager mViewPager;
    // flag for Internet connection status
        Boolean isInternetPresent = false;

        // Connection detector class
        ConnectionDetector cd;

        // Alert Dialog Manager
        AlertDialogManager alert = new AlertDialogManager();

        // Google Places
        GooglePlaces googlePlaces;

        // Places List
        PlacesList nearPlaces;

        // GPS Location
        GPSTracker gps;

        // Button
        Button btnShowOnMap;

        // Progress dialog
        ProgressDialog pDialog;

        // Places Listview
        ListView lv;

        // ListItems data
        ArrayList<HashMap<String, String>> placesListItems = new ArrayList<HashMap<String,String>>();


        // KEY Strings
        public static String KEY_REFERENCE = "reference"; // id of the place
        public static String KEY_NAME = "name"; // name of the place
        public static String KEY_VICINITY = "vicinity"; // Place area name

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

        // Set up the action bar.
        final ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        // Create the adapter that will return a fragment for each of the three
        // primary sections of the activity.
        mSectionsPagerAdapter = new SectionsPagerAdapter(
                getSupportFragmentManager());

        // Set up the ViewPager with the sections adapter.
        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        // When swiping between different sections, select the corresponding
        // tab. We can also use ActionBar.Tab#select() to do this if we have
        // a reference to the Tab.
        mViewPager
                .setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
                    @Override
                    public void onPageSelected(int position) {
                        actionBar.setSelectedNavigationItem(position);
                    }
                });

        // For each of the sections in the app, add a tab to the action bar.
        for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
            // Create a tab with text corresponding to the page title defined by
            // the adapter. Also specify this Activity object, which implements
            // the TabListener interface, as the callback (listener) for when
            // this tab is selected.
            actionBar.addTab(actionBar.newTab()
                    .setText(mSectionsPagerAdapter.getPageTitle(i))
                    .setTabListener(this));
        }

        cd = new ConnectionDetector(getApplicationContext());

        // Check if Internet present
        isInternetPresent = cd.isConnectingToInternet();
        if (!isInternetPresent) {
            // Internet Connection is not present
            alert.showAlertDialog(MainActivity.this, "Internet Connection Error",
                    "Please connect to working Internet connection", false);
            // stop executing code by return
            return;
        }

        // creating GPS Class object
        gps = new GPSTracker(this);

        // check if GPS location can get
        if (gps.canGetLocation()) {
            Log.d("Your Location", "latitude:" + gps.getLatitude() + ", longitude: " + gps.getLongitude());
        } else {
            // Can't get user's current location
            alert.showAlertDialog(MainActivity.this, "GPS Status",
                    "Couldn't get location information. Please enable GPS",
                    false);
            // stop executing code by return
            return;
        }

        // Getting listview
        lv = (ListView) findViewById(R.id.list);

        // button show on map
        //btnShowOnMap = (Button) findViewById(R.id.btn_show_map);

        // calling background Async task to load Google Places
        // After getting places from Google all the data is shown in listview

        new LoadPlaces().execute();

        /** Button click event for shown on map 
        btnShowOnMap.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                Intent i = new Intent(getApplicationContext(),
                        PlacesMapActivity.class);
                // Sending user current geo location
                i.putExtra("user_latitude", Double.toString(gps.getLatitude()));
                i.putExtra("user_longitude", Double.toString(gps.getLongitude()));

                // passing near places to map activity
                i.putExtra("near_places", nearPlaces);
                // staring activity
                startActivity(i);
            }
        });
        */

        /**
         * ListItem click event
         * On selecting a listitem SinglePlaceActivity is launched
         * */
        lv.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                // getting values from selected ListItem
                String reference = ((TextView) view.findViewById(R.id.reference)).getText().toString();

                // Starting new intent
                Intent in = new Intent(getApplicationContext(),
                        SinglePlaceActivity.class);

                // Sending place refrence id to single place activity
                // place refrence id used to get "Place full details"
                in.putExtra(KEY_REFERENCE, reference);
                startActivity(in);
            }
        });
    }

    /**
     * Background Async Task to Load Google places
     * */


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @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);
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab,
            FragmentTransaction fragmentTransaction) {
        // When the given tab is selected, switch to the corresponding page in
        // the ViewPager.
        mViewPager.setCurrentItem(tab.getPosition());
    }

    @Override
    public void onTabUnselected(ActionBar.Tab tab,
            FragmentTransaction fragmentTransaction) {
    }

    @Override
    public void onTabReselected(ActionBar.Tab tab,
            FragmentTransaction fragmentTransaction) {
    }

    /**
     * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
     * one of the sections/tabs/pages.
     */
    public class SectionsPagerAdapter extends FragmentPagerAdapter {

        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a PlaceholderFragment (defined as a static inner class
            // below).
            return PlaceholderFragment.newInstance(position + 1);
        }

        @Override
        public int getCount() {
            // Show 3 total pages.
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
            case 0:
                return getString(R.string.police).toUpperCase(l);
            case 1:
                return getString(R.string.hospital).toUpperCase(l);
            case 2:
                return getString(R.string.restaurant).toUpperCase(l);
            }
            return null;
        }
    }

    /**
     * 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_main, container,
                    false);
            TextView textView = (TextView) rootView
                    .findViewById(R.id.section_label);
            textView.setText(Integer.toString(getArguments().getInt(
                    ARG_SECTION_NUMBER)));

            return rootView;
        }
    }

    class LoadPlaces extends AsyncTask<String, String, String> {


        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(MainActivity.this);
            pDialog.setMessage(Html.fromHtml("<b>Search</b><br/>Loading Places..."));
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(false);
            pDialog.show();
        }

        /**
         * getting Places JSON
         * */
        protected String doInBackground(String... args) {
            // creating Places class object
            googlePlaces = new GooglePlaces();

            try {
                String types = null;
                //String types = "police|hospital|train_station"; // Listing places only cafes, restaurants

                // Radius in meters - increase this value if you don't find any places
                double radius = 10000; // 1000 meters 

                // get nearest places
                nearPlaces = googlePlaces.search(gps.getLatitude(),
                        gps.getLongitude(), radius, types);


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

        protected void onPostExecute(String file_url) {
            // dismiss the dialog after getting all products
            pDialog.dismiss();
            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    /**
                     * Updating parsed Places into LISTVIEW
                     * */
                    // Get json response status
                    String status = nearPlaces.status;

                    // Check for all possible status
                    if(status.equals("OK")){
                        // Successfully got places details
                        if (nearPlaces.results != null) {
                            // loop through each place
                            for (Place p : nearPlaces.results) {
                                HashMap<String, String> map = new HashMap<String, String>();

                                // Place reference won't display in listview - it will be hidden
                                // Place reference is used to get "place full details"
                                map.put(KEY_REFERENCE, p.reference);

                                // Place name
                                map.put(KEY_NAME, p.name);


                                // adding HashMap to ArrayList
                                placesListItems.add(map);
                            }
                            // list adapter
                            ListAdapter adapter = new SimpleAdapter(MainActivity.this, placesListItems,
                                    R.layout.list_item,
                                    new String[] { KEY_REFERENCE, KEY_NAME}, new int[] {
                                            R.id.reference, R.id.name });

                            // Adding data into listview
                            lv.setAdapter(adapter);
                        }
                    }
                    else if(status.equals("ZERO_RESULTS")){
                        // Zero results found
                        alert.showAlertDialog(MainActivity.this, "Near Places",
                                "Sorry no places found. Try to change the types of places",
                                false);
                    }
                    else if(status.equals("UNKNOWN_ERROR"))
                    {
                        alert.showAlertDialog(MainActivity.this, "Places Error",
                                "Sorry unknown error occured.",
                                false);
                    }
                    else if(status.equals("OVER_QUERY_LIMIT"))
                    {
                        alert.showAlertDialog(MainActivity.this, "Places Error",
                                "Sorry query limit to google places is reached",
                                false);
                    }
                    else if(status.equals("REQUEST_DENIED"))
                    {
                        alert.showAlertDialog(MainActivity.this, "Places Error",
                                "Sorry error occured. Request is denied",
                                false);
                    }
                    else if(status.equals("INVALID_REQUEST"))
                    {
                        alert.showAlertDialog(MainActivity.this, "Places Error",
                                "Sorry error occured. Invalid Request",
                                false);
                    }
                    else
                    {
                        alert.showAlertDialog(MainActivity.this, "Places Error",
                                "Sorry error occured.",
                                false);
                    }
                }
            });

        }

    }

}

整个源代码是here。请有人帮我这个,或者告诉我一种在这个应用程序中集成可转换标签或导航抽屉的方法。

提前致谢

0 个答案:

没有答案