Android Json 和 AsyncTask 错误
Android Json and AsyncTask Error
我编写了一个代码，使用 JSON 表单将数据从 android 应用程序发送到数据库，但是我在发送时遇到了一些错误。
这是class注册：
package com.subhi.tabhost;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.Patterns;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.regex.Pattern;
import AddUser.AllUsersLoadSpinner;
import ConnectionDetector.ConnectionDetector;
import SpinnerFirstLoad.MultiSelectionSpinner;
import SpinnerFirstLoad.PlayersLoadSpinner;
import SpinnerFirstLoad.TeamsLoadSpinner;
public class Registeration extends AppCompatActivity {
ConnectionDetector connectionDetector;
private MultiSelectionSpinner multiSelectionSpinner;
private MultiSelectionSpinner PlayersSelectSpinier;
Button save;
TextView name, email, userexists;
ArrayList<String> TeamsList = new ArrayList<String>();
ArrayList<String> UsersList = new ArrayList<String>();
ArrayList<String> PlayersList = new ArrayList<String>();
public static final String MyPREFERENCES = "MyPrefs";
public static final String Name = "nameKey";
public static final String EMAIL = "emailKey";
SharedPreferences sharedpreferences;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_registeration);
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
String restoredText = sharedpreferences.getString(Name, null);
/* if (restoredText != null) {
// Intent intent = new Intent(getApplicationContext(), MainMenu.class);
//startActivity(intent);
// finish();
}*/
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
// if (connectionDetector.isConnectingToInternet()) {
name = (TextView) findViewById(R.id.name);
email = (TextView) findViewById(R.id.email);
userexists = (TextView) findViewById(R.id.btnLinkToLoginScreen);
save = (Button) findViewById(R.id.btnRegister);
multiSelectionSpinner = (MultiSelectionSpinner) findViewById(R.id.mySpinner);
PlayersSelectSpinier = (MultiSelectionSpinner) findViewById(R.id.mySpinner2);
TeamsLoadSpinner x1 = new TeamsLoadSpinner(this);
x1.execute("http://192.168.1.106/add/index.php");
AllUsersLoadSpinner allUsersLoadSpinner = new AllUsersLoadSpinner(this);
allUsersLoadSpinner.execute("http://192.168.1.106/add/allusers.php");
PlayersLoadSpinner x2 = new PlayersLoadSpinner(this);
x2.execute("http://192.168.1.106/add/print.php");
save.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
InsertData adduser = new InsertData();
String txtname = name.getText().toString();
String txtemail = email.getText().toString();
if (txtname.equals(""))
Toast.makeText(getApplicationContext(), "UserName Cannot Be Empty", Toast.LENGTH_LONG).show();
else {
if (txtemail.equals(""))
Toast.makeText(getApplicationContext(), "Email Cannot Be Empty ", Toast.LENGTH_LONG).show();
else {
if (isValidEmail(txtemail)) {
boolean x = false;
for (int i = 0; i < UsersList.size(); i++) {
if (UsersList.get(i).equals(txtname)) {
x = true;
}
}
if (x == false) {
SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putString(Name, txtname);
editor.putString(EMAIL, txtemail);
editor.commit();
adduser.execute("192.168.1.106/add/add.php", txtname, txtemail, multiSelectionSpinner.getSelectedItemsAsString(), PlayersSelectSpinier.getSelectedItemsAsString());
} else {
//Toast.makeText(getApplicationContext(),"USER EXISTS",Toast.LENGTH_LONG).show();
userexists.setText("User Alerady Exists, Please Choose Differnent User name ");
}
} else
Toast.makeText(getApplicationContext(), "Please Enter A valid Email", Toast.LENGTH_LONG).show();
}
}
}
});
// }else {
// Internet connection is not present
// Ask user to connect to Internet
// showAlertDialog(Registeration.this, "No Internet Connection",
// "You don't have internet connection.", false);
// }
}
public void showAlertDialog(final Context context, String title, String message, Boolean status) {
AlertDialog alertDialog = new AlertDialog.Builder(context).create();
// Setting Dialog Title
alertDialog.setTitle(title);
// Setting Dialog Message
alertDialog.setMessage(message);
// Setting alert dialog icon
alertDialog.setIcon((status) ? R.drawable.success : R.drawable.fail);
// Setting OK Button
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
// Showing Alert Message
alertDialog.show();
}
private boolean isValidEmail(String email) {
Pattern pattern = Patterns.EMAIL_ADDRESS;
return pattern.matcher(email).matches();
}
public void SetTeams(ArrayList<String> list) {
TeamsList = list;
String[] stockArr = new String[TeamsList.size()];
stockArr = TeamsList.toArray(stockArr);
multiSelectionSpinner.setItems(stockArr);
}
public void SetUsers(ArrayList<String> list) {
UsersList = list;
}
public void SetPlayers(ArrayList<String> players) {
PlayersList = players;
String[] stockArr = new String[PlayersList.size()];
stockArr = PlayersList.toArray(stockArr);
PlayersSelectSpinier.setItems(stockArr);
}
private class InsertData extends AsyncTask<String,Void,Boolean>
{
@Override
protected Boolean doInBackground(String... urls) {
OutputStream os=null;
InputStream is=null;
HttpURLConnection conn=null;
try {
URL url =new URL(urls[0]);
JSONObject jsonObject=new JSONObject();
jsonObject.put("UserName", urls[1]);
jsonObject.put("Email", urls[2]);
jsonObject.put("Teams", urls[3]);
jsonObject.put("Players", urls[4]);
String message=jsonObject.toString();
Log.d(message, "Test");
conn=(HttpURLConnection)url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setFixedLengthStreamingMode(message.getBytes().length);
conn.setRequestProperty("Content-Type", "application/json; charset=utf-8");
conn.setRequestProperty("X-Requested-With", "XMLHttpRequest");
conn.connect();
os=new BufferedOutputStream(conn.getOutputStream());
os.write(message.getBytes());
os.flush();
is=conn.getInputStream();
} catch (MalformedURLException e) {
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_LONG).show();;
e.printStackTrace();
return false;
} catch (IOException e) {
Toast.makeText(getApplicationContext(),e.toString(),Toast.LENGTH_LONG).show();;
e.printStackTrace();
return false;
} catch (JSONException e) {
e.printStackTrace();
}
finally {
try {
assert os != null;
os.close();
assert is != null;
is.close();
} catch (IOException e) {
e.printStackTrace();
}
conn.disconnect();
}
return true;
}
@Override
protected void onPostExecute(Boolean result) {
if(result)
{
Toast.makeText(getApplicationContext(),"Insert Success",Toast.LENGTH_LONG).show();;
}
else {
Toast.makeText(getApplicationContext(),"Insert Fail",Toast.LENGTH_LONG).show();;
}
}
}
}
这是 php 代码脚本：
<?php
require ('config.php');
$con=mysqli_connect($servername,$username,$password,$db);
$json = file_get_contents('php://input');
$obj = json_decode($json,true);
$txtname=$obj['UserName'];//$_POST['txtname'];
$txtemail=$obj['Email'];//$_POST['txtemail'];
$txtteam=$obj['Teams'];//$_POST['txtemail'];
$txtplayer=$obj['Players'];//$_POST['txtemail'];
mysqli_query($con,"insert into user (UserName,Email,TeamsInterested,PlayersIterested) values('$txtname','$txtemail','$txtteam','$txtplayer') ");
echo "Inserted";
?>
这是日志猫：
02-11 12:06:15.197 2301-2319/? E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #3
Process: com.subhi.tabhost, PID: 2301
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
Caused by: java.lang.NullPointerException
at com.subhi.tabhost.Registeration$InsertData.doInBackground(Registeration.java:287)
at com.subhi.tabhost.Registeration$InsertData.doInBackground(Registeration.java:221)
at android.os.AsyncTask.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
02-11 12:06:15.201 530-843/? W/ActivityManager: Force finishing activity com.subhi.tabhost/.Registeration
02-11 12:06:15.265 153-502/? W/genymotion_audio: out_write() limiting sleep time 42152 to 39909
02-11 12:06:15.469 530-843/? D/dalvikvm: GC_FOR_ALLOC freed 621K, 27% free 9319K/12628K, paused 6ms, total 7ms
02-11 12:06:15.481 530-843/? D/dalvikvm: GC_FOR_ALLOC freed 376K, 27% free 9315K/12628K, paused 12ms, total 12ms
02-11 12:06:15.497 530-545/? D/dalvikvm: GC_FOR_ALLOC freed 13K, 23% free 9791K/12628K, paused 12ms, total 12ms
02-11 12:06:15.501 530-545/? I/dalvikvm-heap: Grow heap (frag case) to 10.747MB for 1127532-byte allocation
02-11 12:06:15.509 530-539/? D/dalvikvm: GC_FOR_ALLOC freed 15K, 21% free 10876K/13732K, paused 11ms, total 11ms
并且日志 cat 错误显示在代码中的两个位置：
1- `os.close();`
2- private class InsertData extends AsyncTask<String,Void,Boolean>
所以如果有人可以帮助我吗？！
我决定使用 Volley 库，它比 HttpUrlConnection 简单多了。
遵循本教程并快乐编码
我编写了一个代码，使用 JSON 表单将数据从 android 应用程序发送到数据库，但是我在发送时遇到了一些错误。
这是class注册：
package com.subhi.tabhost;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.Patterns;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.regex.Pattern;
import AddUser.AllUsersLoadSpinner;
import ConnectionDetector.ConnectionDetector;
import SpinnerFirstLoad.MultiSelectionSpinner;
import SpinnerFirstLoad.PlayersLoadSpinner;
import SpinnerFirstLoad.TeamsLoadSpinner;
public class Registeration extends AppCompatActivity {
ConnectionDetector connectionDetector;
private MultiSelectionSpinner multiSelectionSpinner;
private MultiSelectionSpinner PlayersSelectSpinier;
Button save;
TextView name, email, userexists;
ArrayList<String> TeamsList = new ArrayList<String>();
ArrayList<String> UsersList = new ArrayList<String>();
ArrayList<String> PlayersList = new ArrayList<String>();
public static final String MyPREFERENCES = "MyPrefs";
public static final String Name = "nameKey";
public static final String EMAIL = "emailKey";
SharedPreferences sharedpreferences;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_registeration);
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
String restoredText = sharedpreferences.getString(Name, null);
/* if (restoredText != null) {
// Intent intent = new Intent(getApplicationContext(), MainMenu.class);
//startActivity(intent);
// finish();
}*/
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
// if (connectionDetector.isConnectingToInternet()) {
name = (TextView) findViewById(R.id.name);
email = (TextView) findViewById(R.id.email);
userexists = (TextView) findViewById(R.id.btnLinkToLoginScreen);
save = (Button) findViewById(R.id.btnRegister);
multiSelectionSpinner = (MultiSelectionSpinner) findViewById(R.id.mySpinner);
PlayersSelectSpinier = (MultiSelectionSpinner) findViewById(R.id.mySpinner2);
TeamsLoadSpinner x1 = new TeamsLoadSpinner(this);
x1.execute("http://192.168.1.106/add/index.php");
AllUsersLoadSpinner allUsersLoadSpinner = new AllUsersLoadSpinner(this);
allUsersLoadSpinner.execute("http://192.168.1.106/add/allusers.php");
PlayersLoadSpinner x2 = new PlayersLoadSpinner(this);
x2.execute("http://192.168.1.106/add/print.php");
save.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
InsertData adduser = new InsertData();
String txtname = name.getText().toString();
String txtemail = email.getText().toString();
if (txtname.equals(""))
Toast.makeText(getApplicationContext(), "UserName Cannot Be Empty", Toast.LENGTH_LONG).show();
else {
if (txtemail.equals(""))
Toast.makeText(getApplicationContext(), "Email Cannot Be Empty ", Toast.LENGTH_LONG).show();
else {
if (isValidEmail(txtemail)) {
boolean x = false;
for (int i = 0; i < UsersList.size(); i++) {
if (UsersList.get(i).equals(txtname)) {
x = true;
}
}
if (x == false) {
SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putString(Name, txtname);
editor.putString(EMAIL, txtemail);
editor.commit();
adduser.execute("192.168.1.106/add/add.php", txtname, txtemail, multiSelectionSpinner.getSelectedItemsAsString(), PlayersSelectSpinier.getSelectedItemsAsString());
} else {
//Toast.makeText(getApplicationContext(),"USER EXISTS",Toast.LENGTH_LONG).show();
userexists.setText("User Alerady Exists, Please Choose Differnent User name ");
}
} else
Toast.makeText(getApplicationContext(), "Please Enter A valid Email", Toast.LENGTH_LONG).show();
}
}
}
});
// }else {
// Internet connection is not present
// Ask user to connect to Internet
// showAlertDialog(Registeration.this, "No Internet Connection",
// "You don't have internet connection.", false);
// }
}
public void showAlertDialog(final Context context, String title, String message, Boolean status) {
AlertDialog alertDialog = new AlertDialog.Builder(context).create();
// Setting Dialog Title
alertDialog.setTitle(title);
// Setting Dialog Message
alertDialog.setMessage(message);
// Setting alert dialog icon
alertDialog.setIcon((status) ? R.drawable.success : R.drawable.fail);
// Setting OK Button
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
// Showing Alert Message
alertDialog.show();
}
private boolean isValidEmail(String email) {
Pattern pattern = Patterns.EMAIL_ADDRESS;
return pattern.matcher(email).matches();
}
public void SetTeams(ArrayList<String> list) {
TeamsList = list;
String[] stockArr = new String[TeamsList.size()];
stockArr = TeamsList.toArray(stockArr);
multiSelectionSpinner.setItems(stockArr);
}
public void SetUsers(ArrayList<String> list) {
UsersList = list;
}
public void SetPlayers(ArrayList<String> players) {
PlayersList = players;
String[] stockArr = new String[PlayersList.size()];
stockArr = PlayersList.toArray(stockArr);
PlayersSelectSpinier.setItems(stockArr);
}
private class InsertData extends AsyncTask<String,Void,Boolean>
{
@Override
protected Boolean doInBackground(String... urls) {
OutputStream os=null;
InputStream is=null;
HttpURLConnection conn=null;
try {
URL url =new URL(urls[0]);
JSONObject jsonObject=new JSONObject();
jsonObject.put("UserName", urls[1]);
jsonObject.put("Email", urls[2]);
jsonObject.put("Teams", urls[3]);
jsonObject.put("Players", urls[4]);
String message=jsonObject.toString();
Log.d(message, "Test");
conn=(HttpURLConnection)url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setFixedLengthStreamingMode(message.getBytes().length);
conn.setRequestProperty("Content-Type", "application/json; charset=utf-8");
conn.setRequestProperty("X-Requested-With", "XMLHttpRequest");
conn.connect();
os=new BufferedOutputStream(conn.getOutputStream());
os.write(message.getBytes());
os.flush();
is=conn.getInputStream();
} catch (MalformedURLException e) {
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_LONG).show();;
e.printStackTrace();
return false;
} catch (IOException e) {
Toast.makeText(getApplicationContext(),e.toString(),Toast.LENGTH_LONG).show();;
e.printStackTrace();
return false;
} catch (JSONException e) {
e.printStackTrace();
}
finally {
try {
assert os != null;
os.close();
assert is != null;
is.close();
} catch (IOException e) {
e.printStackTrace();
}
conn.disconnect();
}
return true;
}
@Override
protected void onPostExecute(Boolean result) {
if(result)
{
Toast.makeText(getApplicationContext(),"Insert Success",Toast.LENGTH_LONG).show();;
}
else {
Toast.makeText(getApplicationContext(),"Insert Fail",Toast.LENGTH_LONG).show();;
}
}
}
}
这是 php 代码脚本：
<?php
require ('config.php');
$con=mysqli_connect($servername,$username,$password,$db);
$json = file_get_contents('php://input');
$obj = json_decode($json,true);
$txtname=$obj['UserName'];//$_POST['txtname'];
$txtemail=$obj['Email'];//$_POST['txtemail'];
$txtteam=$obj['Teams'];//$_POST['txtemail'];
$txtplayer=$obj['Players'];//$_POST['txtemail'];
mysqli_query($con,"insert into user (UserName,Email,TeamsInterested,PlayersIterested) values('$txtname','$txtemail','$txtteam','$txtplayer') ");
echo "Inserted";
?>
这是日志猫：
02-11 12:06:15.197 2301-2319/? E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #3
Process: com.subhi.tabhost, PID: 2301
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
Caused by: java.lang.NullPointerException
at com.subhi.tabhost.Registeration$InsertData.doInBackground(Registeration.java:287)
at com.subhi.tabhost.Registeration$InsertData.doInBackground(Registeration.java:221)
at android.os.AsyncTask.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
02-11 12:06:15.201 530-843/? W/ActivityManager: Force finishing activity com.subhi.tabhost/.Registeration
02-11 12:06:15.265 153-502/? W/genymotion_audio: out_write() limiting sleep time 42152 to 39909
02-11 12:06:15.469 530-843/? D/dalvikvm: GC_FOR_ALLOC freed 621K, 27% free 9319K/12628K, paused 6ms, total 7ms
02-11 12:06:15.481 530-843/? D/dalvikvm: GC_FOR_ALLOC freed 376K, 27% free 9315K/12628K, paused 12ms, total 12ms
02-11 12:06:15.497 530-545/? D/dalvikvm: GC_FOR_ALLOC freed 13K, 23% free 9791K/12628K, paused 12ms, total 12ms
02-11 12:06:15.501 530-545/? I/dalvikvm-heap: Grow heap (frag case) to 10.747MB for 1127532-byte allocation
02-11 12:06:15.509 530-539/? D/dalvikvm: GC_FOR_ALLOC freed 15K, 21% free 10876K/13732K, paused 11ms, total 11ms
并且日志 cat 错误显示在代码中的两个位置：
1- `os.close();`
2- private class InsertData extends AsyncTask<String,Void,Boolean>
所以如果有人可以帮助我吗？！
我决定使用 Volley 库，它比 HttpUrlConnection 简单多了。
遵循本教程并快乐编码