我是 php
的新手现在尝试从 MySQL
检索数据到安卓。
这是我的work_details 表
在RetrieveTotalHours 函数中,我想从MySQL
中检索min id time-in 和max id time-out通过php
到android最后使用下面的代码获取总小时数。
假设 ID 是 3 ,所以我想得到 timeIn where id=3
, timeOut 其中id=25
.到目前为止,这是我尝试过的。
public void RetrieveTotalHours( final String ID) // ID(twd)=3
{
class GetHours extends AsyncTask<Void,Void,String> {
ProgressDialog loading;
@Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(getActivity(),"Fetching...","Wait...",false,false);
}
@Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
loading.dismiss();
showHours(s);
}
@Override
protected String doInBackground(Void... params) {
RequestHandler rh = new RequestHandler();
String s = rh.sendGetRequestParam(Configs.RETRIEVE_HOURS,ID);
return s;
}
}
GetHours ge = new GetHours();
ge.execute();
}
private void showHours(String json) {
try {
JSONObject jsonObject = new JSONObject(json);
JSONArray result = jsonObject.getJSONArray(Configs.TAG_JSON_ARRAY);
JSONObject c = result.getJSONObject(0);
String MiNtimeIn = c.getString(Configs.TAG_IN);
String MaXtimeOut=c.getString(Configs.TAG_OUT);
long difference = 0;
if (MiNtimeIn > MaXtimeOut) {
difference = (MaXtimeOut + (24 * 60) - MiNtimeIn) - (1 * 60);
minutes = (int) (difference % 60);
hours = (int) ((difference / 60) % (24 * 60));
totalHours.setText(("Total hours : " + hours + ":" + minutes));
} else {
// .....
}
total.setText(hours);
} catch (JSONException e) {
e.printStackTrace();
}
}
Retrieve_hours.php
<?php
define('HOST','127.0.0.1:3307');
define('USER','root');
define('PASS','');
define('DB','androiddb');
$con = mysqli_connect(HOST,USER,PASS,DB) or die('unable to connect');
$twd= $_GET['id'];
$sql = "select timeIn, timeOut from work_details WHERE twd = '".$twd."' AND id IN
(SELECT MIN(id) FROM work_details WHERE twd ='".$twd."' UNION SELECT MAX(id) FROM work_details WHERE twd='".$twd."')";
$res = mysqli_query($con,$sql);
$result=array();
while($row=mysqli_fetch_array($res)){
array_push($result,array('id'=>$row[0],'timeIn'=>$row[1],'timeOut'=>$row[2]));
}
echo json_encode($res);
mysqli_close($con);
?>
配置
public static final String TAG_IN="timeIn";
public static final String TAG_OUT="timeOut";
错误
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ org.json.JSONException: Value <br of type java.lang.String cannot be converted to JSONObject
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at org.json.JSON.typeMismatch(JSON.java:111)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at org.json.JSONObject.<init>(JSONObject.java:159)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at org.json.JSONObject.<init>(JSONObject.java:172)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails.showHours(Edit_WorkDetails.java:248)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails.access$000(Edit_WorkDetails.java:46)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails$1GetHours.onPostExecute(Edit_WorkDetails.java:232)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails$1GetHours.onPostExecute(Edit_WorkDetails.java:220)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.AsyncTask.finish(AsyncTask.java:632)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.AsyncTask.access$600(AsyncTask.java:177)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.Handler.dispatchMessage(Handler.java:102)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.Looper.loop(Looper.java:146)
01-10 19:31:47.355 1298-1298/com.example.project.myapplication W/System.err﹕ at android.app.ActivityThread.main(ActivityThread.java:5602)
01-10 19:31:47.360 1298-1298/com.example.project.myapplication W/System.err﹕ at java.lang.reflect.Method.invokeNative(Native Method)
01-10 19:31:47.360 1298-1298/com.example.project.myapplication W/System.err﹕ at java.lang.reflect.Method.invoke(Method.java:515)
01-10 19:31:47.360 1298-1298/com.example.project.myapplication W/System.err﹕ at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
01-10 19:31:47.360 1298-1298/com.example.project.myapplication W/System.err﹕ at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
01-10 19:31:47.360 1298-1298/com.example.project.myapplication W/System.err﹕ at dalvik.system.NativeStart.main(Native Method)
01-10 19:31:47.380 1298-1298/com.example.project.myapplication D/AbsListView﹕ Get MotionRecognitionManager
已编辑
String MiNtimeIn = c.getString(Configs.TAG_IN);
String MaXtimeOut=c.getString(Configs.TAG_OUT);
假设 ID(twd) 是 8,我应该得到 21:52 的 timeIn 和 1:52 的 timeOut。 MiNtimeIn 应该显示 21:52(id 3),MaXtimeOut 应该显示 1:52(id 4)
最佳答案
替换此部分:
$result=array();
while($row=mysqli_fetch_array($res)){
array_push($result,array('id'=>$row[0],'timeIn'=>$row[1],'timeOut'=>$row[2]));
}
echo (json_encode(array("result"=>$result)));
与:
echo json_encode($res);
您创建了很多数组,当您在 while 循环中进行推送时,您将数组推送到 $result 数组中,然后当您回显时,您将所有结果放入另一个数组中。这更复杂。
关于java - 从 MySQL php 中的特定列获取最大 ID 和最小 ID,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/34704631/