android - 从搜索结果中复制来自自定义数组适配器的 View

Question

我有一个填充 listView 的自定义 arrayAdapter。当我第一次加载 listActivity 时，从 AsyncTask 加载的信息正确加载，没有任何重复。

在同一个 Activity 中，我使用 ActionBar 中的搜索字段，但出于某种原因，当我使用相同的 arrayAdapter 显示结果时，结果总是重复，有时甚至是三倍。

我已经对本网站和其他网站上的答案进行了双重和三次检查，但似乎无法提出有效的解决方案。如果您没有完整的解决方案，也许您可​​以将我推向正确的方向。这是我的 arrayAdapter:

public class JobsAdapter extends ArrayAdapter<String> {

     public static LayoutInflater inflater = null;
     public ArrayList<HashMap<String, String>> jobList;
     public String jobId;
     public Context context;
     public int layoutResourceId;


    public static class ViewHolder {

        TextView jid;
        TextView jid2;
        TextView jcn;
        TextView jd;
        TextView js;

      }

    public JobsAdapter(Context context, int layoutResourceId){

        super(context, layoutResourceId);
        this.context = context;
    }

    public JobsAdapter(Context context, int layoutResourceId, ArrayList<HashMap<String, String>> jobList){

        super(context, layoutResourceId);
        this.context = context;
        this.jobList = jobList;
    }

    @Override
    public int getCount() {
        return jobList.size();
    }

    public Item getItem(Item position) {
        return position;
    }

    @Override
    public long getItemId(int position) {
        return position; 
    }

    @Override
    public boolean hasStableIds() {
        return true;
    }


    public View getView(int position, View convertView, ViewGroup parent) {     
        ViewHolder holder;
        View v = convertView;

        if(v == null)
        {
            LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v = inflater.inflate(R.layout.list_edit_job_item, parent, false);
            holder = new ViewHolder();
            holder.jid = (TextView) v.findViewById(R.id.jobid);
            holder.jid2 = (TextView) v.findViewById(R.id.jobID);
            holder.jcn = (TextView) v.findViewById(R.id.jobClientName);
            holder.jd = (TextView) v.findViewById(R.id.jobDescription);
            holder.js = (TextView) v.findViewById(R.id.jobStatus);

            v.setTag(holder);
        }
        else
        {
            holder = (ViewHolder) v.getTag();
        }

        HashMap<String, String> i = jobList.get(position);

        String sjid = i.get("jobID");
        String sjid2 = i.get("jobID");
        String sjcn = i.get("clientName");
        String sjd = i.get("description");
        String sjs = i.get("status");

        if(holder.jid != null)
            {
                holder.jid.setText(sjid);
            }
        if(holder.jid2 != null)
            {
                holder.jid2.setText(sjid2);
            }
        if(holder.jcn != null)
            {
                holder.jcn.setText(sjcn);
            }
        if(holder.jd != null)
            {
                holder.jd.setText(sjd);
            }
        if(holder.js != null)
            {
                holder.js.setText(sjs);
            }

        return v;


    }

    public void updateList(ArrayList<HashMap<String, String>> newJobList) {
        jobList.addAll(newJobList);
        this.notifyDataSetChanged();
    }

    public void addAllItems(ArrayList<HashMap<String, String>> newJobList) {
        jobList.clear();
        jobList.addAll(newJobList);
        this.notifyDataSetChanged();
    }


    @Override

    public int getViewTypeCount() {                 

        return getCount();
    }

    @Override
    public int getItemViewType(int position) {

        return position;
    }

}

这是我的主要 Activity :

public class DisplayEditJobs extends ListActivity implements OnScrollListener, OnQueryTextListener {


    private static final String TAG_JOB_JOBID = "jobID";
    private static final String TAG_JOB_CLIENTID = "clientID"; 
    private static final String TAG_JOB_CLIENT_NAME = "clientName";
    private static final String TAG_JOB_TITLE = "clientID";
    private static final String TAG_JOB_STATUS = "status";
    private static final String TAG_JOB_DATE_CREATED = "date_created";
    private static final String TAG_JOB_NOTES = "notes";   
    private static final String TAG_JOB_DESCRIPTION = "description";
    private static final String TAG_SUCCESS = "success";   
    private static final String TAG_JOBS = "jobs";

    Aleph0 adapter = new Aleph0();


    private ProgressDialog pDialog;
    public String jobID, userPermissions;
    public EditText notes, description, createdDate;
    public Spinner status, client;
    public Button AddJobButton, pickCreatedDateButton; 

    ArrayList<User> clientList;
    ArrayList<String> technicianIDList;
    List<String> labels;
    ActionBar actionBar;
    ListView lv;
    int success = 0 ;
    int page = 1;
    int currentPage = 1;
    int threshold = 3;

    private SearchView searchView;
    private static final String display_jobs_url = "http://com.tradeport.on.ca/view_all_jobs.php";
    String query = "";

    JSONParser jsonParser = new JSONParser();

    JSONArray user_session = null;
    int pagedefault = 1;
    JSONArray jobs = null;

    Button btnLoadMore;

    TextView pageid;
    int newpageid;
    public JobsAdapter myAdapter;
    ArrayList<HashMap<String, String>> jobsList;




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

        ActionBar actionBar = getActionBar();
        actionBar.setTitle("Choose a Job to Edit");
        actionBar.setDisplayHomeAsUpEnabled(true); 

        jobsList = new ArrayList<HashMap<String, String>>();
        myAdapter = new JobsAdapter(DisplayEditJobs.this, R.layout.list_edit_job_item, jobsList);
        getListView().setOnScrollListener(this); 
        new LoadAllJobs().execute();

        lv = getListView();

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

                String jobid = ((TextView) view.findViewById(R.id.jobid)).getText().toString();
                Intent in = new Intent(getApplicationContext(),Jobs.class);
                in.putExtra(TAG_JOB_JOBID, jobid);
                startActivityForResult(in, 100);
            }


        });



    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (resultCode == 100) {

            Intent intent = getIntent();
            finish();
            startActivity(intent);
        }

    }

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

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(DisplayEditJobs.this);
            pDialog.setMessage("Loading Jobs. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(false);
            pDialog.show();
        }

        protected String doInBackground(String... args) {

            SharedPreferences pref = getApplicationContext().getSharedPreferences("USER_SESSION", 0);
            String session_username = pref.getString("username", null);
            String session_key = pref.getString("key", null);



            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair("tag", "view_all_jobs"));
            params.add(new BasicNameValuePair("username", session_username));
            params.add(new BasicNameValuePair("key", session_key ));
            params.add(new BasicNameValuePair("page", String.valueOf(page)));

            JSONObject json = jsonParser.makeHttpRequest(display_jobs_url, "POST", params);

            Log.d("All Instruments: ", json.toString());

            try {

                success = json.getInt(TAG_SUCCESS);

                if (success == 1) {

                    jobs = json.getJSONArray(TAG_JOBS);

                    for (int i = 0; i < jobs.length(); i++) {
                        JSONObject c = jobs.getJSONObject(i);

                        String jobid = c.getString(TAG_JOB_JOBID);
                        String clientName = c.getString(TAG_JOB_CLIENT_NAME);
                        String status = c.getString(TAG_JOB_STATUS);
                        String description = c.getString(TAG_JOB_DESCRIPTION);

                        HashMap<String, String> map = new HashMap<String, String>();

                        map.put(TAG_JOB_JOBID, jobid);
                        map.put(TAG_JOB_CLIENT_NAME, "Client : "+clientName);
                        map.put(TAG_JOB_STATUS, status);
                        map.put(TAG_JOB_DESCRIPTION, description);

                        jobsList.add(map);
                    }

                } else {

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

            return null;
        }

        protected void onPostExecute(String file_url) {


            pDialog.dismiss();
            Context context = getBaseContext();
            myAdapter = new JobsAdapter(context, R.layout.list_edit_job_item, jobsList);
            lv.setAdapter(myAdapter); 



        }

    }

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

        @Override
        protected void onPreExecute() {
            super.onPreExecute();

        }

        protected String doInBackground(String... args) {

            jobs = null;
            success = 0;
            SharedPreferences pref = getApplicationContext().getSharedPreferences("USER_SESSION", 0);
            String session_username = pref.getString("username", null);
            String session_key = pref.getString("key", null);



            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair("tag", "view_all_jobs"));
            params.add(new BasicNameValuePair("username", session_username));
            params.add(new BasicNameValuePair("key", session_key ));
            params.add(new BasicNameValuePair("page", String.valueOf(page)));

            JSONObject json = jsonParser.makeHttpRequest(display_jobs_url, "POST", params);

            Log.d("All Instruments: ", json.toString());

            try {

                if (success == 1) {
                    jobsList.clear();

                    jobs = json.getJSONArray(TAG_JOBS);

                    for (int i = 0; i < jobs.length(); i++) {
                        JSONObject c = jobs.getJSONObject(i);

                        String jobid = c.getString(TAG_JOB_JOBID);
                        String clientName = c.getString(TAG_JOB_CLIENT_NAME);
                        String status = c.getString(TAG_JOB_STATUS);
                        String description = c.getString(TAG_JOB_DESCRIPTION);

                        HashMap<String, String> map = new HashMap<String, String>();

                        map.put(TAG_JOB_JOBID, jobid);
                        map.put(TAG_JOB_CLIENT_NAME, "Client : "+clientName);
                        map.put(TAG_JOB_STATUS, status);
                        map.put(TAG_JOB_DESCRIPTION, description);

                        jobsList.add(map);
                    }

                } else {

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

            return null;
        }



        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) 
        {
            if(success == 1)
                { 
                    myAdapter.updateList(jobsList); 
                }
        }

    }


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

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();


        }

        /**
         * getting All products from url
         * */
        protected String doInBackground(String... args) {
            jobsList.clear();
            myAdapter.clear();
            jobs = null;
            success = 0;
            SharedPreferences pref = getApplicationContext().getSharedPreferences("USER_SESSION", 0);
            String session_username = pref.getString("username", null);
            String session_key = pref.getString("key", null);


            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair("tag", "view_all_jobs"));
            params.add(new BasicNameValuePair("username", session_username));
            params.add(new BasicNameValuePair("key", session_key ));
            params.add(new BasicNameValuePair("keyword", query ));
            params.add(new BasicNameValuePair("page", String.valueOf(page)));

            JSONObject json = jsonParser.makeHttpRequest(display_jobs_url, "POST", params);


            try {

                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {

                    jobs = json.getJSONArray(TAG_JOBS);

                    for (int i = 0; i < jobs.length(); i++) {
                        JSONObject c = jobs.getJSONObject(i);

                        String jobid = c.getString(TAG_JOB_JOBID);
                        String clientName = c.getString(TAG_JOB_CLIENT_NAME);
                        String status = c.getString(TAG_JOB_STATUS);
                        String description = c.getString(TAG_JOB_DESCRIPTION);

                        HashMap<String, String> map = new HashMap<String, String>();

                        map.put(TAG_JOB_JOBID, jobid);
                        map.put(TAG_JOB_CLIENT_NAME, "Client : "+clientName);
                        map.put(TAG_JOB_STATUS, status);
                        map.put(TAG_JOB_DESCRIPTION, description);

                        jobsList.add(map);

                    }


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

            return null;
        }



        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {

            myAdapter.updateList(jobsList);   
        }

    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        getMenuInflater().inflate(R.menu.display_edit_instruments, menu);
        searchView = (SearchView) menu.findItem(R.id.action_search).getActionView();        
        searchView.setOnQueryTextListener(this);
        searchView.setSubmitButtonEnabled(true);

        int id = searchView.getContext().getResources().getIdentifier("android:id/search_src_text", null, null);

        TextView textView = (TextView) searchView.findViewById(id);
        textView.setTextColor(Color.WHITE);

        return true;
    }


    @Override
    public void onScroll(AbsListView view, int firstVisible,
            int visibleCount, int totalCount) {


    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {

         if ((scrollState == SCROLL_STATE_IDLE) && (query.equals(""))) {
                if (lv.getLastVisiblePosition() >= lv.getCount() - 1 - threshold) {

                    final int index = lv.getFirstVisiblePosition();
                    View v = lv.getChildAt(0);
                    final int top = (v == null) ? 0 : v.getTop();

                    currentPage++;
                    page++;
                    new updateJobs().execute();
                    lv.setSelectionFromTop(index, top);



                }
            }

    }


    class Aleph0 extends BaseAdapter {
        int count = 10; 
        public int getCount() { return count; }
        public Object getItem(int pos) { return pos; }
        public long getItemId(int pos) { return pos; }

        public View getView(int pos, View v, ViewGroup p) {
            if(pos!=count-1)
            {
                TextView view = new TextView(DisplayEditJobs.this);
                view.setText("entry " + pos);
                return view;
            }
            TextView view = new TextView(DisplayEditJobs.this);
            view.setText("Loading.. " + pos);
            return view;

        }
    }

    @Override
    public boolean onQueryTextChange(String newText) {
        if (!TextUtils.isEmpty(newText))
        {
          query = newText.toString();
          new searchUpdateJobs().execute();

         }

        return false;
    }

    @Override
    public boolean onQueryTextSubmit(String query) {
        return false;
    }


}

Answer 1

在进行更多挖掘和测试后，我找到了一个快速解决方法。这可能不是最好的解决方案，因为每次像这样调用类时我都会重置适配器

protected void onPostExecute(String file_url) {
        HashSet<HashMap<String, String>> unique = new HashSet<HashMap<String, String>>();
        unique.addAll(jobsList);
        jobsList.clear();
        jobsList.addAll(unique);   

        //this resets the adapter   

        myAdapter = new JobsAdapter(DisplayEditJobs.this, R.layout.list_edit_job_item, jobsList);
        lv.setAdapter(myAdapter); 
    }

我确信这比实际的更新方法更消耗资源。如果有人有任何想法，我愿意接受任何建议。