java - 调用 objadapter.removeItem(po);仅当列表被删除时

Question

我想知道如何实现这一目标。

我在 Activity A 中有一个 listView 。当检测到长按时，它将转到 checkMaxID(ID,iD); 。如果iD为最大，则会显示成功，删除列表，最后刷新列表。否则会显示list无法删除并且不会经过objadapter.removeItem(po);。

Now what I want to achieve is call objadapter.removeItem(po); only when the list get deleted. If not,
objadapter.removeItem(po); will not be called.

    listViewUpdate.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
                public boolean onItemLongClick(final AdapterView<?> p, View v, final int po, long id) {

                    iD = details1.get(po).getID();
                    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
                    builder.setTitle("Delete");
                    builder.setMessage("Are you sure you want to delete?");
                    builder.setIcon(android.R.drawable.ic_dialog_alert);
                    builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int ii) {
                            checkMaxID(ID,iD);
                            objadapter.removeItem(po); // only call when list get deleted
                            RetrieveTotalHours(ID);

                        }
                    });

                    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener()

                            {
                                public void onClick(DialogInterface dialog, int ii) {
                                    dialog.dismiss();
                                }
                            }

                    );
                    builder.show();
                    return true;
                }
            });


   public void checkMaxID(final int foreignKey,final String iD)
    {
        class check extends AsyncTask<Void,Void,String>{
            // ProgressDialog loading;
            @Override
            protected void onPreExecute() {
                super.onPreExecute();
                // loading = ProgressDialog.show(Edit_Staff.this,"Updating...","Wait...",false,false);
            }

            @Override
            protected void onPostExecute(String s) {
                super.onPostExecute(s);
                // loading.dismiss();
                Toast.makeText(getActivity(), s, Toast.LENGTH_LONG).show();
            }

            @Override
            protected String doInBackground(Void... params) {
                HashMap<String,String> hashMap = new HashMap<>();
                hashMap.put(Configs.KEY_ID, iD);
                hashMap.put(Configs.KEY_TWD, String.valueOf(foreignKey));
                RequestHandler rh = new RequestHandler();
                String s = rh.sendPostRequest(Configs.URL_CHECK_ID, hashMap);
                return s;
            }
        }

      check ue = new check();
        ue.execute();
        }

checkID.php

<?php
if(isset($_POST['id'], $_POST['twd'])){
    /*Importing our db connection script*/
    require_once('dbConnect.php');
    /* check connection */
    if (mysqli_connect_errno()) {
        printf("Connect failed: %s\n", mysqli_connect_error());
        exit();
    }
    $id = mysqli_real_escape_string($con, $_POST['id']);
    $twd = mysqli_real_escape_string($con, $_POST['twd']);

    $sql ="SELECT MAX(id) as MaxId FROM work_details WHERE twd = '$twd'";

    if ($result = mysqli_query($con, $sql)) {
        /* fetch associative array */
        if ($row = mysqli_fetch_row($result)) {
            if($row[0] === $id){
                $sql ="DELETE FROM work_details WHERE id='$id';";
                if ($result = mysqli_query($con, $sql)) {
                    echo 'success';
                }else{
                    echo 'failed';
                }
            }
            else{
            echo 'list cannot be deleted ';
        }

        }

        /* free result set */

    }
    /* close connection */
    mysqli_close($con);
}
?>

Answer 1

您需要在 PHP 脚本中添加一些 json:

<?php
$json = array();
if(isset($_POST['id'], $_POST['twd'])){
    /*Importing our db connection script*/
    require_once('dbConnect.php');
    /* check connection */
    if (mysqli_connect_errno()) {
        printf("Connect failed: %s\n", mysqli_connect_error());
        exit();
    }
    $id = mysqli_real_escape_string($con, $_POST['id']);
    $twd = mysqli_real_escape_string($con, $_POST['twd']);

    $sql ="SELECT MAX(id) as MaxId FROM work_details WHERE twd = '$twd'";

    if ($result = mysqli_query($con, $sql)) {
        /* fetch associative array */
        if ($row = mysqli_fetch_row($result)) {
            if($row[0] === $id){
                $sql ="DELETE FROM work_details WHERE id='$id';";
                if ($result = mysqli_query($con, $sql)) {
                    echo 'success';
                    $json['success'] = true;
                    $json['message'] = 'delete is successful';
                }else{
                    $json['success'] = false;
                    $json['message'] = 'list cannot be deleted';
                }
            }else{
                $json['success'] = false;
                $json['message'] = '($row[0] !== $id)';         
            }
        } else{
            $json['success'] = false;
            $json['message'] = 'select is unsuccessful';            
        }
    /* close connection */
    mysqli_close($con);
    }
}
?>

并在你的java中解析它:

@Override
protected void onPostExecute(String s) {
    super.onPostExecute(s);
    Toast.makeText(getActivity(), s, Toast.LENGTH_LONG).show();
    try{
        JSONObject json = new JSONObject(s);
        if(json.getBoolean("success")){
            objadapter.removeItem(po)
        }else{
            Toast.makeText(getActivity(), 
            json.getString("message"), 
            Toast.LENGTH_LONG).show();
        }       
    }catch(JSONException ex){

    }
}