如何使用 onItemClick in listview 从 mysql 获取数据?

Question

我有一个自定义列表视图，其中包含从mysql获取数据的文本视图。我想在单击项目时从文本视图中获取内容。 我试过这个，

mList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String value = mList.getItemAtPosition(position).toString();
Toast.makeText(getBaseContext(), value, Toast.LENGTH_LONG).show();
}
});

但它返回com.wanto.sispaktriwanto.init.Penyakit@c05cb5c.

谁能帮我解决这个问题？ 谢谢。

这是模型代码：

package com.wanto.sispaktriwanto.init;    
public class Penyakit {
private String penyakit_nama;
public String getpenyakit_nama() {
return penyakit_nama;
}
public void setpenyakit_nama(String penyakit_nama) {
this.penyakit_nama = penyakit_nama;
}
} 

这是从 mysql 获取数据的代码：

package com.wanto.sispaktriwanto.server;    
import com.wanto.sispaktriwanto.init.HasilKonsul;
import com.wanto.sispaktriwanto.init.Penyakit;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONObject;
import java.util.ArrayList;
public class GetDetailPenyakit {
public static ArrayList<Penyakit> getDetail(String postvariable) {
String detail = "";
ArrayList<Penyakit> MyArraylist = new ArrayList<>();
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("http://10.0.2.2/android_sispak/getDetailPenyakit.php");
try {
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("detail", postvariable));
httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse httpResponse = httpClient.execute(httpPost);
detail = EntityUtils.toString(httpResponse.getEntity());
JSONArray jsonArray = new JSONArray(detail);
for (int i = 0; i < jsonArray.length(); i++) {
Penyakit genres = new Penyakit();
JSONObject MyJsonObject = jsonArray.getJSONObject(i);
genres.setpenyakit_nama(MyJsonObject.getString("nama"));
MyArraylist.add(genres);
}

} catch (Exception e) {
e.printStackTrace();
}
return MyArraylist;
}
}

这是适配器代码：

package com.wanto.sispaktriwanto.adapter;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;
import com.wanto.sispaktriwanto.R;
import com.wanto.sispaktriwanto.init.Penyakit;
import java.util.List;
public class PenyakitAdapter extends ArrayAdapter<Penyakit> {
private final List<Penyakit> list;
public PenyakitAdapter(Context context, int resource, List<Penyakit> list) {
super(context, resource, list);
this.list = list;
}
static class ViewHolder {
protected TextView penyakitNama;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder = null;
if (convertView == null) {
LayoutInflater inflator = LayoutInflater.from(getContext());
convertView = inflator.inflate(R.layout.row_penyakit, null);
viewHolder = new ViewHolder();
viewHolder.penyakitNama = (TextView) convertView.findViewById(R.id.row_namap);
convertView.setTag(viewHolder);
convertView.setTag(R.id.row_namap, viewHolder.penyakitNama);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.penyakitNama.setText(list.get(position).getpenyakit_nama());
return convertView;
}
}

这是活动代码：

package com.wanto.sispaktriwanto;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.Toast;

import com.wanto.sispaktriwanto.adapter.PenyakitAdapter;
import com.wanto.sispaktriwanto.init.Penyakit;
import com.wanto.sispaktriwanto.server.GetDetailPenyakit;
import com.wanto.sispaktriwanto.server.PenyakitJsonParser;
import java.util.ArrayList;
public class DetailPenyakit extends AppCompatActivity {

Context context;
ArrayList<Penyakit> array_list;
GetDetailPenyakit JsonGetDetail;
ListView mList;
String konsultasiS;
static String detailresponse;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detail_penyakit);

Intent intent = getIntent();
detailresponse = intent.getExtras().getString("detail");
context = this;
new asyncTask_getPenyakit().execute();
}
public class asyncTask_getPenyakit extends AsyncTask<Void, Void, Void> {
ProgressDialog dialog = new ProgressDialog(context);
@Override
protected void onPreExecute() {
dialog.setTitle("Please wait...");
dialog.setMessage("Loading Info Penyakit!");
dialog.show();
array_list = new ArrayList<>();
JsonGetDetail = new GetDetailPenyakit();
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
array_list = JsonGetDetail.getDetail(detailresponse);
return null;
}
protected void onPostExecute(Void s) {

mList = (ListView) findViewById(R.id.detail_listView);
final PenyakitAdapter detailAdapter = new PenyakitAdapter(context, R.layout.row_penyakit, array_list);
mList.setAdapter(detailAdapter);
mList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
String value = mList.getItemAtPosition(position).toString();
Toast.makeText(getBaseContext(), value, Toast.LENGTH_LONG).show();
}
});
super.onPostExecute(s);
dialog.dismiss();
}
}
}

这是活动 xml：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.wanto.sispaktriwanto.DetailPenyakit">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="100">
<ListView
android:id="@+id/detail_listView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:divider="@drawable/divider"
android:dividerHeight="1sp"
android:layout_weight="80"/>
</LinearLayout>
</android.support.constraint.ConstraintLayout>

和行 XML：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:background="#ffffff"
android:orientation="vertical">
<TextView
android:id="@+id/row_namap"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_marginLeft="20dp"
android:maxLines="1"
android:text="sss"
android:gravity="center"
android:textAppearance="?android:attr/textAppearanceMedium"/>    
</LinearLayout>

Answer 1

通过使用此代码，您可以获取文本视图的当前值。

mList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
String contactId = ((TextView) view.findViewById(R.id.row_namap)).getText().toString();
Toast.makeText(getBaseContext(), value, Toast.LENGTH_LONG).show();
}
});

Answer 2

有一个错误， 您的活动中已经有 arraylist，所以试试这个，

mList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
String value =  array_list.get(position).getpenyakit_nama();
Toast.makeText(getBaseContext(), value, Toast.LENGTH_LONG).show();
}
});

请让我知道这是否有效

Answer 3

String value = mList.getItemAtPosition(position).toString();

它将得到Penyakit对象。 如果要获取penyakit_nama值，请使用以下代码。

String value = ((Penyakit)mList.getItemAtPosition(position)).getpenyakit_nama();

因为 ArrayAdapter 的泛型类型是<Penyakit>，getItemAtPosition()将返回Penyakit对象