listview隐藏方向更改android

Question

I am using custom list view inside fragment(From Api). on orientation change data is still in array list and also list view get notified but it hides when screen rotates. here is the code:

public class FragNotice extends Fragment implements View.OnClickListener {

    ListAdapter listAdapter;
    ListView listView;
    EditText editTextNotice;
    private Button btnSearch;
    private Button btnClear;
    private int incre = 1;
    private boolean boolScroll = true;

    public FragNotice() {
        // Required empty public constructor
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Thread.setDefaultUncaughtExceptionHandler(new ExceptionHandler(getActivity()));
        setRetainInstance(true);
        search(true);
    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return init(inflater.inflate(R.layout.notice_activity, container, false));
    }

    private View init(View view) {
        editTextNotice = (EditText) view.findViewById(R.id.editTextNotice);
        btnSearch = (Button) view.findViewById(R.id.btnSearch);
        btnSearch.setOnClickListener(this);
        btnClear = (Button) view.findViewById(R.id.btnClear);
        btnClear.setOnClickListener(this);
        listView = (ListView) view.findViewById(R.id.listViewNotice);
        listView.setOnScrollListener(onScrollListener());
        return view;
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        if (listAdapter==null) {
            listAdapter=new ListAdapter(getActivity(), new ArrayList<ListRowItem>());
            listView.setAdapter(listAdapter);
            listAdapter.notifyDataSetChanged();
        }
    }

    AsyncRequest.OnAsyncRequestComplete onAsyncRequestComplete = new AsyncRequest
            .OnAsyncRequestComplete() {


        @Override
        public void asyncResponse(String response, int apiKey) {
                switch (apiKey) {
                    case 1:
                        listView(response);
                        break;
                }
        }
    };

    @Override
    public void onClick(View v) {
        if (v.getId() == R.id.btnClear) {
            incre = 1;
            boolScroll = true;
            editTextNotice.setText(null);
            if (listAdapter != null)
                listAdapter.clear();
            search(true);
        } else if (v.getId() == R.id.btnSearch) {
            String std = editTextNotice.getText().toString();

            if (std.trim().length() > 1) {
                incre = 1;
                boolScroll = true;
                if (listAdapter != null)
                    listAdapter.clear();
                try {
                    InputMethodManager imm = (InputMethodManager) getActivity().getSystemService
                            (Context.INPUT_METHOD_SERVICE);
                    imm.hideSoftInputFromWindow(new View(getActivity()).getWindowToken(),
                            InputMethodManager.HIDE_NOT_ALWAYS);
                } catch (Exception e) {
                    // TODO: handle exception
                }
                search(false);
            } else
                Toast.makeText(getActivity(),
                        "Please enter atleast two character.", Toast.LENGTH_LONG)
                        .show();
        }
    }


    class ListAdapter extends ArrayAdapter<ListRowItem> {
        private final Context context;


        public ListAdapter(Context asyncTask, java.util.List<ListRowItem> items) {
            super(asyncTask, R.layout.notice_listitem, items);
            this.context = asyncTask;
        }

        public View getView(int position, View convertView, ViewGroup parent) {
            final ViewHolder holder;
            final ListRowItem rowItem = getItem(position);

            LayoutInflater mInflater = (LayoutInflater) context
                    .getSystemService(context.LAYOUT_INFLATER_SERVICE);
            if (convertView == null) {
                convertView = mInflater.inflate(R.layout.notice_listitem, parent, false);
                holder = new ViewHolder();
                holder.txtSno = (TextView) convertView.findViewById(R.id.txtSno);
                holder.txtNoticePublishDate = (TextView) convertView.findViewById(R.id
                        .txtNoticePublishDate);
                holder.btnView = (Button) convertView.findViewById(R.id.btnView);
                holder.txtNoticeDescription = (TextView) convertView.findViewById(R.id
                        .txtNoticeDescription);
                holder.txtNoticeName = (TextView) convertView.findViewById(R.id.txtNoticeName);


                convertView.setTag(holder);
            } else
                holder = (ViewHolder) convertView.getTag();
            holder.txtSno.setText(String.valueOf(position + 1));
            holder.txtNoticeDescription.setText(new AppUtility().TitleCase(rowItem.getDescription
                    ()));
            holder.txtNoticeName.setText(new AppUtility().TitleCase(rowItem.getFileTitle()));

            try {
                holder.txtNoticePublishDate.setText(String.valueOf((new SimpleDateFormat("dd MMM " +
                        "yyyy HH:mm:ss", Locale.US)).format((new SimpleDateFormat
                        ("yyyy-MM-dd'T'HH:mm:ss", Locale.US)).parse(rowItem.getUpdateDate()))));
            } catch (ParseException e) {
                holder.txtNoticePublishDate.setText(new AppUtility().TitleCase(rowItem
                        .getUpdateDate()));
            }
            holder.btnView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                }
            });
            return convertView;
        }

        /*private view holder class*/
        private class ViewHolder {
            TextView txtSno;
            TextView txtNoticeName;
            TextView txtNoticeDescription;
            TextView txtNoticePublishDate;
            Button btnView;

        }
    }

    class ListRowItem {
        private final String FileTitle;
        private final String Description;
        private final String ContentType;
        private final int DocumentUploadID;
        private final String UpdateDate;

        ListRowItem() {
            this.FileTitle = "";
            this.Description = "";
            this.ContentType = "";
            this.DocumentUploadID = 0;
            this.UpdateDate = "";
        }

        ListRowItem(String fileTitle, String description, String contentType, int
                documentUploadID, String updateDate) {
            this.FileTitle = fileTitle;
            this.Description = description;
            this.ContentType = contentType;
            this.DocumentUploadID = documentUploadID;
            this.UpdateDate = updateDate;
        }

        public String getFileTitle() {
            return FileTitle;
        }

        public int getDocumentUploadID() {

            return DocumentUploadID;
        }

        public String getUpdateDate() {

            return UpdateDate;
        }

        public String getDescription() {
            return Description;
        }

        public String getContentType() {

            return ContentType;
        }
    }

    private void listView(String response) {
        try {
            ArrayList<ListRowItem> lstItem;
            if(listAdapter==null){
                Type listType = new TypeToken<ArrayList<ListRowItem>>() {
                }.getType();
                lstItem = new Gson().fromJson(response, listType);
                listAdapter = new ListAdapter(getActivity(), lstItem);
            } else {
                Type listType = new TypeToken<ArrayList<ListRowItem>>() {
                }.getType();
                lstItem = new Gson().fromJson(response, listType);
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                    listAdapter.addAll(lstItem);
                } else {
                    for (ListRowItem items : lstItem) {
                        listAdapter.add(items);
                    }
                }
            }
            if (listAdapter != null)
                listAdapter.notifyDataSetChanged();
        } catch (Exception e) {

        }
    }


    private AbsListView.OnScrollListener onScrollListener() {
        return new AbsListView.OnScrollListener() {


            @Override
            public void onScrollStateChanged(AbsListView view, int scrollState) {
                int threshold = 5;
                int count = listView.getCount();

                if (scrollState == SCROLL_STATE_IDLE) {
                    if (listView.getLastVisiblePosition() >= count - threshold) {

                        if (boolScroll) {
                            if (editTextNotice.getText().toString().trim().length() > 0)
                                search(false);
                            else
                                search(true);

                        }
                    }
                }
            }

            @Override
            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
                                 int totalItemCount) {
            }
        };
    }

    private void search(boolean bool) {
        String URL;
        if (bool) {
            URL = new SqLite(getActivity()).returnDefaultURI() + "notice/0/" + incre;
            incre = incre + 1;
        } else {
            URL = new SqLite(getActivity()).returnDefaultURI() + "notice/" +
                    editTextNotice.getText().toString().trim() + "/" + incre;
            incre = incre + 1;
        }

        AsyncRequest asyncRequest;
        if (incre > 2)
            asyncRequest = new AsyncRequest(onAsyncRequestComplete, getActivity(), "GET", null,
                    null, 1);
        else
            asyncRequest = new AsyncRequest(onAsyncRequestComplete, getActivity(), "GET", null,
                    "Fetching data", 1);

        asyncRequest.execute(URL);
    }

}

Answer 1

You need to load the data into the ListView again. You are binding the ListView to an adapter, you need to do it in onConfigurationChanged() method.

Answer 2

When orientation changes the activity reloads again.So you have to override onConfigurationChanged method.

@Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {

            //Your Code Here
        }
        if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
            //Your Code Here
        }
    }

Answer 3

在资源中创建目录布局-将您的.xml文件复制到Edittext并根据横向布局对齐并设置Edittext和Button。如果listview没有足够的空间来显示横向布局，则可能解决了您的问题

Answer 4

In onViewCreated(View view, Bundle savedInstanceState) method above you are setting new empty arraylist every time. So the previous items which are loaded are removed from adapter even though it is retained by setRetainInstance(true)

So you should have a Field that holds the arraylist and pass that field to adapter

private ArrayList<ListRowItem> listItems = new ArrayList<>()

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    if (listAdapter==null) {
        listAdapter=new ListAdapter(getActivity(), listItems);//pass the Arraylist here
        listView.setAdapter(listAdapter);
        listAdapter.notifyDataSetChanged();
    }
}

Then in private void listView(String response) method, add items to that listview created above as

   listItems = new Gson().fromJson(response, listType);
   listAdapter.notifyDataSetChanged();