我是安卓新手。我遇到的问题是当我运行我的应用程序时它不显示从 mysql 在线服务器获取的数据。虽然我的 php 脚本很好，因为当我在浏览器中打开我的 php 脚本链接时，它显示了这个 JSON 字符串
{"ID":"1","mobileName":"Nokia","mobileModel":"NA-85","mobilePrice":"8500"}。
但是当我从我的 android 应用程序调用这个脚本时，它在我的真实设备或模拟器上运行，它在该行显示错误。
int mobid = json.getInt("ID");
日志:
03-23 22:38:29.151 1918-2302/com.example.abdul.sql E/Buffer Error﹕ Error converting result org.json.JSONException: Value <html><body><script of type java.lang.String cannot be converted to JSONObject
03-23 22:38:29.242 1918-1918/com.example.abdul.sql D/AndroidRuntime﹕ Shutting down VM
--------- beginning of crash
03-23 22:38:29.242 1918-1918/com.example.abdul.sql E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.abdul.sql, PID: 1918
java.lang.NullPointerException: Attempt to invoke virtual method 'int org.json.JSONObject.getInt(java.lang.String)' on a null object reference
at com.example.abdul.sql.MainActivity$Connectingdb.onPostExecute(MainActivity.java:172)
at com.example.abdul.sql.MainActivity$Connectingdb.onPostExecute(MainActivity.java:80)
at android.os.AsyncTask.finish(AsyncTask.java:632)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
主 Activity .java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URLEncodedUtils;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
TextView tv;
String textview = null;
static JSONObject jObj ;
static String json = "";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.textView1);
Button b2 = (Button) findViewById(R.id.button1);
b2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent i2 = new Intent(MainActivity.this,menuList.class);
startActivity(i2);
}
});
Button connectdb = (Button) findViewById(R.id.button1);
connectdb.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
new Connectingdb().execute();
}
});
}
class Connectingdb extends AsyncTask<String, String, JSONObject> {
/**
* Before starting background thread Show Progress Dialog
* */
boolean failure = false;
private ProgressDialog pDialog;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Attempting connect...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected JSONObject doInBackground(String... args) {
InputStream is = null;
// Making HTTP request
try {
// check for request method
{
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("http://codedefault.base.pk/products.php");
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
json = sb.toString();
jObj = new JSONObject(json);
is.close();
return jObj;
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
return null;
}
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(JSONObject json) {
try {
int mobid = json.getInt("ID");
String mobilename = json.getString("mobileName");
String mobileModel = json.getString("mobileModel");
int mobilePrice = json.getInt("mobileprice");
display("mobile Id= "+mobid+"\nmobileName = "+mobilename +"\n mobile model = "+mobileModel +"\n mobile price = "+mobilePrice+"\n>>>>>>>>>>>>>>>\n");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
pDialog.dismiss();
}
}
public void display(String m){
tv.setText(m);
}
}
最佳答案
问题出在您的免费服务器中，这意味着您的在线 Web 服务器将 cookie 发送到未处理的 android。现在您可以使用除 base.pk,byethost.com 以外的其他虚拟主机站点。使用 ueuo.com 摆脱这些问题。
关于java - Android 应用程序不从 MYSQL 获取数据，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/36185467/