ListView仅显示arraylist中的第一项

Question

列表视图仅显示数据中的第一项。如何使其显示数组列表中的所有数据。我认为它是因为我在地图中使用相同的键，如何更改它并使其显示。任何帮助表示赞赏。

public class MainActivity extends AppCompatActivity implements ActionBar.TabListener{


    SectionsPagerAdapter mSectionsPagerAdapter;

    ViewPager mViewPager;

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

        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

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

        final ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                actionBar.setSelectedNavigationItem(position);
            }
        });

        for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
            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.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        int id = item.getItemId();

        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab, FragmentTransaction ft) {
        mViewPager.setCurrentItem(tab.getPosition());
    }

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

    }

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

    }


    public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {

            switch (position) {
                case 0:
                    return PlaceholderFragment.newInstance(position + 1);
                case 1:
                    return PlaceholderFragment.newInstance(position + 1);
                case 2:
                    return MapTabFragment.newInstance(position + 1);
            }

            return null;
        }

        @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.title_section1).toUpperCase(l);
                case 1:
                    return getString(R.string.title_section2).toUpperCase(l);
                case 2:
                    return getString(R.string.title_section3).toUpperCase(l);
            }
            return null;
        }
    }


    public static class PlaceholderFragment extends Fragment {

        private static final String ARG_SECTION_NUMBER = "section_number";

        TextView text;

        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);

            text = (TextView) rootView.findViewById(R.id.section_label);
            text.setText("placeholder");

            return rootView;
        }
    }

    public static class MapTabFragment extends SupportMapFragment implements
            OnMapReadyCallback {

        private static final String ARG_SECTION_NUMBER = "section_number";

        private GoogleMap mMap;
        private Marker marker;


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

        public MapTabFragment() {
        }

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

            Log.d("MyMap", "onResume");
            setUpMapIfNeeded();
        }

        private void setUpMapIfNeeded() {

            if (mMap == null) {

                Log.d("MyMap", "setUpMapIfNeeded");

                getMapAsync(this);
            }
        }

        @Override
        public void onMapReady(GoogleMap googleMap) {
            Log.d("MyMap", "onMapReady");
            mMap = googleMap;
            setUpMap();
        }

        private void setUpMap() {

            mMap.setMyLocationEnabled(true);
            mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
            mMap.getUiSettings().setMapToolbarEnabled(false);


            mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {

                @Override
                public void onMapClick(LatLng point) {

                    Log.d("MyMap", "MapClick");

                    //remove previously placed Marker
                    if (marker != null) {
                        marker.remove();
                    }

                    //place marker where user just clicked
                    marker = mMap.addMarker(new MarkerOptions().position(point).title("Marker")
                            .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA)));

                    Log.d("MyMap", "MapClick After Add Marker");

                }
            });

        }
    }
}

Answer 1

那是因为您实际上只向HashMap添加了一个ArrayList。

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

for(menuDescription x:data){
    //prepare new HashMap
    HashMap<String, String> map = new HashMap<String, String>();
    map.put("Title", x.getTitle());
    map.put("Description", x.getDescription());
    //add HashMap to ArrayList
    albumsList.add(map);
}