android - 将列表从 Activity 发送到 fragment android

Question

我遇到了以下问题。将 Assets 文件夹中的本地 xml 文件解析为列表后，我想将此解析后的列表发送到 fragment ，该 fragment 应在 ListView 中显示此列表中的特定条目。

解析有效， ListView 有效，但我不确定如何通过 intent bundle extra 将列表发送到 fragment 以及如何在 fragment 中获得此 Intent 。

在这个例子中，我想发送 List<RowItem> pois到 static fragment class RouteItemFragment .错误在

pois = getActivity().getIntent().getParcelableArrayListExtra("pois"); 

留言:

inferred type for type parameter T is not within its bound. should implement android.os.parcelable

有人给我提示吗？

public class RouteView extends ActionBarActivity implements ActionBar.TabListener {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide
     * fragments for each of the sections. We use a
     * {@link FragmentPagerAdapter} derivative, which will keep every
     * loaded fragment in memory. If this becomes too memory intensive, it
     * may be best to switch to a
     * {@link android.support.v4.app.FragmentStatePagerAdapter}.
     *
     */

    Integer citySave;
    Integer routeSave;
    String routeTitel;
    private static int NUM_ITEMS = 2;
    SectionsPagerAdapter mSectionsPagerAdapter;
    ListView listView;
    List<RowItem> pois;

    /**
     * The {@link ViewPager} that will host the section contents.
     */
    ViewPager mViewPager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_route_view);
        Bundle b = getIntent().getExtras();
        citySave = b.getInt("stadt");
        routeSave = b.getInt("route");
        routeTitel = b.getString("titel_route");
        b.putString("titel_route",routeTitel);
        b.putInt("route", routeSave);
        RouteItemFragment fragobj = new RouteItemFragment();
        fragobj.setArguments(b);

        try {
            PoiParser parser = new PoiParser();
            pois = parser.parse(getAssets().open("poi_passau1.xml"));
            b.putParcelableArrayList("pois", (java.util.ArrayList<? extends android.os.Parcelable>) pois);
        } catch (IOException e) {
            e.printStackTrace();
        }




        // 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));
        }
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.route_view, menu);
        return true;
    }

    @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).
            switch (position){
                case 0:
                    return RouteItemFragment.newInstance(position);
                case 1:
                    return MapFragment.newInstance(position);
                default:
                    return PlaceholderFragment.newInstance(position);
            }
        }

        @Override
        public int getCount() {
            // Show 2 total pages.
            return NUM_ITEMS;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
                case 0:
                    return getString(R.string.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
            }
            return null;
        }
    }

    public static class RouteItemFragment extends ListFragment implements AdapterView.OnItemClickListener {
        private static final String ARG_SECTION_NUMBER = "section_number";

        ListView listView;
        List<RowItem> pois;

        public static RouteItemFragment newInstance(int sectionNumber) {
            RouteItemFragment fragment = new RouteItemFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        public RouteItemFragment() {

        }

        @Override
        public void onActivityCreated(Bundle savedInstanceState) {

            super.onActivityCreated(savedInstanceState);

            pois  = getActivity().getIntent().getParcelableArrayListExtra("pois");
            CityListViewAdapter adapter = new CityListViewAdapter(getActivity(), R.layout.row_items, pois);
                /**Collections.sort(pois, new Comparator<RowItem>() {
                    public int compare(RowItem s1, RowItem s2) {
                        return s1.getID().compareTo(s2.getID());
                    }
                });*/
                listView.setAdapter(adapter);
                listView.setOnItemClickListener(this);

        }

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

            View rootView = inflater.inflate(R.layout.fragment_route_item, container, false);
            TextView textView = (TextView) rootView.findViewById(R.id.textRouteitem);
            listView = (ListView) rootView.findViewById(android.R.id.list);
            textView.setText(String.format(getResources().getString(R.string.routeViewfragment)) + " "
                    + getActivity().getIntent().getStringExtra("titel_route"));
            return rootView;
        }

        @Override
        public void onItemClick(AdapterView<?> adapterView, View parent, int position, long l) {
            Intent intent = new Intent();
            intent.setClass(getActivity(), PoiView.class);
            RowItem pois = (RowItem) getListView().getItemAtPosition(position);
            Bundle b = new Bundle();
            //b.putInt("stadt", cities.getID());
            b.putParcelableArrayList("titel_stadt", pois);
            intent.putExtras(b);
            startActivity(intent);
        }

    }

    public static class MapFragment extends Fragment implements
            GooglePlayServicesClient.ConnectionCallbacks,
            GooglePlayServicesClient.OnConnectionFailedListener {

        private static final String ARG_SECTION_NUMBER = "section_number";
        private GoogleMap mMap;

        /**
         * Returns a new instance of this fragment for the given section
         * number.
         */
        public static MapFragment newInstance(int sectionNumber) {
            MapFragment fragment = new MapFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

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

        }
        public void onResume() {
            super.onResume();
            setUpMapIfNeeded();
        }

        private void setUpMap() {
            mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker"));
        }

        private void setUpMapIfNeeded() {
            // Do a null check to confirm that we have not already instantiated the map.
            if (mMap == null) {
                // Try to obtain the map from the SupportMapFragment.
                mMap = ((SupportMapFragment) getFragmentManager().findFragmentById(R.id.map))
                        .getMap();
                // Check if we were successful in obtaining the map.
                if (mMap != null) {
                    setUpMap();
                }
            }
        }

        public MapFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_map, container, false);
            setUpMapIfNeeded();
            return rootView;
        }

        @Override
        public void onConnected(Bundle bundle) {

        }

        @Override
        public void onDisconnected() {

        }

        @Override
        public void onConnectionFailed(ConnectionResult connectionResult) {

        }
    }

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

    public void onBackPressed() {
        super.onBackPressed();
        Intent intent = new Intent();
        intent.setClass(RouteView.this, RouteChooseActivity.class);
        Bundle b = new Bundle();
        b.putInt("stadt", citySave);
        intent.putExtras(b);
        startActivity(intent);
        finish();
    }

    public void onPause() {
        super.onPause();
        Bundle b = new Bundle();
        b.putInt("stadt", citySave);
        b.putInt("route", routeSave);
        b.putString("route_titel",routeTitel);
        finish();
    }

    public void onResume() {
        super.onResume();

        Bundle b = getIntent().getExtras();
        citySave = b.getInt("stadt");
        routeSave = b.getInt("route");
        routeTitel = b.getString("route_titel");

    }

    public void onStop() {
        super.onStop();
        finish();
    }

    @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.
        switch (item.getItemId()) {
            case R.id.action_stadt:
                setContentView(R.layout.activity_stadt);
                Intent stadt = new Intent(RouteView.this, StadtActivity.class);
                startActivity(stadt);
                return true;
            case R.id.action_route:
                setContentView(R.layout.activity_route_choose);
                Intent route = new Intent(RouteView.this, RouteChooseActivity.class);
                startActivity(route);
                return true;
            case R.id.action_help:
                setContentView(R.layout.activity_help);
                Intent help = new Intent(RouteView.this, Help.class);
                startActivity(help);
                return true;
            case R.id.action_exit:
                moveTaskToBack(true);
                System.exit(0);
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }

}

Poi解析器:

public class PoiParser {
    List<RowItem> pois;
    private RowItem poi;
    private String text;

    public PoiParser() {
        pois = new ArrayList<RowItem>();
    }

    public List<RowItem> getPois() {
        return pois;
    }

    public List<RowItem> parse(InputStream is) {
        XmlPullParserFactory factory = null;
        XmlPullParser parser = null;
        try {
            factory = XmlPullParserFactory.newInstance();
            factory.setNamespaceAware(true);
            parser = factory.newPullParser();

            parser.setInput(is, null);

            int eventType = parser.getEventType();
            while (eventType != XmlPullParser.END_DOCUMENT) {
                String tagname = parser.getName();
                switch (eventType) {
                    case XmlPullParser.START_TAG:
                        if (tagname.equalsIgnoreCase("poi")) {
                            poi = new RowItem();
                        }
                        break;

                    case XmlPullParser.TEXT:
                        text = parser.getText();
                        break;

                    case XmlPullParser.END_TAG:
                        if (tagname.equalsIgnoreCase("poi")) {
                            pois.add(poi);
                        } else if (tagname.equalsIgnoreCase("image")) {
                            poi.setImage(text);
                        } else if (tagname.equalsIgnoreCase("id")) {
                            poi.setID(Integer.parseInt(text));
                        } else if (tagname.equalsIgnoreCase("name")) {
                            poi.setTitle(text);
                        } else if (tagname.equalsIgnoreCase("desc")) {
                            poi.setDesc(text);
                        } else if (tagname.equalsIgnoreCase("imagedesc")) {
                            poi.setImageDesc(text);
                        } else if (tagname.equalsIgnoreCase("infotext")) {
                            poi.setInfoText(text);
                        } else if (tagname.equalsIgnoreCase("audio")) {
                            poi.setAudioPoi(text);
                        } else if (tagname.equalsIgnoreCase("latitude")) {
                            poi.setLatitudePoi(Double.parseDouble(text));
                        } else if (tagname.equalsIgnoreCase("longitude")) {
                            poi.setLongitudePoi(Double.parseDouble(text));
                        }
                        break;

                    default:
                        break;
                }
                eventType = parser.next();
            }

        } catch (XmlPullParserException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return pois;
    }
}

行项

public class RowItem extends ArrayList<Parcelable> {
    private String Bild;
    private String Titel;
    private String Desc;
    private String imageDesc;
    private String infoText;
    private String audioPoi;
    private int ID;
    private double latitudePoi;
    private double longitudePoi;

    public RowItem() {
        this.Bild = Bild;
        this.Titel = Titel;
        this.Desc = Desc;
        this.imageDesc = imageDesc;
        this.infoText = infoText;
        this.audioPoi = audioPoi;
        this.ID = ID;
        this.latitudePoi = latitudePoi;
        this.longitudePoi = longitudePoi;
    }


    public int getID() {return ID;}
    public void setID(int ID) {this.ID = ID;}
    public double getLatitudePoi() {return latitudePoi;}
    public void setLatitudePoi(double latitudePoi) {this.latitudePoi = latitudePoi;}
    public double getLongitudePoi() {return longitudePoi;}
    public void setLongitudePoi(double longitudePoi) {this.longitudePoi = longitudePoi;}
    public String getImage() {
        return Bild;
    }
    public void setImage(String imageId) {
        this.Bild = imageId;
    }
    public String getDesc() {
        return Desc;
    }
    public void setDesc(String desc) {
        this.Desc = desc;
    }
    public String getTitle() {
        return Titel;
    }
    public void setTitle(String title) {
        this.Titel = title;
    }
    public String getImageDesc() {return imageDesc;}
    public void setImageDesc(String imageDesc){this.imageDesc = imageDesc;}
    public String getInfoText() {return infoText;}
    public void setInfoText(String infoText) {this.infoText = infoText;}
    public String getAudioPoi() {return audioPoi;}
    public void setAudioPoi(String audioPoi) {this.audioPoi = audioPoi;}

    @Override
    public String toString() {
        return Titel + "\n" + Desc;
    }

}

Answer 1

您应该为 RowItem 实现 Parcelable 接口(interface)。 并更改您的代码

 b.putParcelableArrayList("pois", pois);

---

public class RowItem implements Parcelable {

private String Bild;
private String Titel;
private String Desc;
private String imageDesc;
private String infoText;
private String audioPoi;
private int ID;
private double latitudePoi;
private double longitudePoi;

public RowItem() {
}

public RowItem(Parcel in) {
    Bild = in.readString();
    Titel = in.readString();
    Desc = in.readString();
    imageDesc = in.readString();
    infoText = in.readString();
    audioPoi = in.readString();
    ID = in.readInt();
    latitudePoi = in.readDouble();
    longitudePoi = in.readDouble();
}

public int getID() {return ID;}
public void setID(int ID) {this.ID = ID;}
public double getLatitudePoi() {return latitudePoi;}
public void setLatitudePoi(double latitudePoi) {this.latitudePoi = latitudePoi;}
public double getLongitudePoi() {return longitudePoi;}
public void setLongitudePoi(double longitudePoi) {this.longitudePoi = longitudePoi;}
public String getImage() {
    return Bild;
}
public void setImage(String imageId) {
    this.Bild = imageId;
}
public String getDesc() {
    return Desc;
}
public void setDesc(String desc) {
    this.Desc = desc;
}
public String getTitle() {
    return Titel;
}
public void setTitle(String title) {
    this.Titel = title;
}
public String getImageDesc() {return imageDesc;}
public void setImageDesc(String imageDesc){this.imageDesc = imageDesc;}
public String getInfoText() {return infoText;}
public void setInfoText(String infoText) {this.infoText = infoText;}
public String getAudioPoi() {return audioPoi;}
public void setAudioPoi(String audioPoi) {this.audioPoi = audioPoi;}

@Override
public String toString() {
    return Titel + "\n" + Desc;
}


@Override
public int describeContents() {
    return 0;
}


@Override
public void writeToParcel(Parcel dest, int flags) {
    dest.writeString(Bild);
    dest.writeString(Titel);
    dest.writeString(Desc);
    dest.writeString(imageDesc);
    dest.writeString(infoText);
    dest.writeString(audioPoi);
    dest.writeInt(ID);
    dest.writeDouble(latitudePoi);
    dest.writeDouble(longitudePoi);
}


@SuppressWarnings("rawtypes")
public static final Parcelable.Creator CREATOR = new Parcelable.Creator() {
    public RowItem createFromParcel(Parcel in) {
        return new RowItem(in);
    }

    public RowItem[] newArray(int size) {
        return new RowItem[size];
    }
};