你好，我想使用Httppost将android应用程序中的字符串发布到PHP网站。应用程序布局由一个文本框和一个发送按钮组成。当我单击发送按钮时，应用程序崩溃，并显示一条消息。不幸的是，应用程序停止工作。请任何机构提供如何解决问题。
主活动.java文件
package com.example.test5;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
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 com.example.test5.R;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity {
Button sendButton;
EditText msgTextField;
/** Called when the activity is first created. */
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// make message text field object
msgTextField = (EditText) findViewById(R.id.msgTextField);
// make send button object
sendButton = (Button) findViewById(R.id.sendButton);
}
// this is the function that gets called when you click the button
public void send(View v)
{
// get the message from the message text box
String msg = msgTextField.getText().toString();
// make sure the fields are not empty
if (msg.length()>0)
{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://thawide.com/androidtest.php");
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("id", "12345"));
nameValuePairs.add(new BasicNameValuePair("message", msg));
try {
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
httpclient.execute(httppost);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
msgTextField.setText(""); // clear text box
Toast.makeText(getBaseContext(),"sucess",Toast.LENGTH_SHORT).show();
}
else
{
// display message if text fields are empty
Toast.makeText(getBaseContext(),"All field are required",Toast.LENGTH_SHORT).show();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Menifest文件
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test5"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET">
</uses-permission>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.test5.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
activity_main.XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<EditText
android:id="@+id/msgTextField"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/sendButton"
android:layout_below="@+id/textView2"
android:layout_marginTop="59dp"
android:ems="10" />
<Button
android:id="@+id/sendButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_below="@+id/msgTextField"
android:layout_marginTop="72dp"
android:onClick="send"
android:text="Send" />
<TextView
android:id="@+id/textView2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/msgTextField"
android:layout_below="@+id/textView1"
android:layout_marginTop="60dp"
android:text="Message" />
</RelativeLayout>
服务器端代码
<?php
// get the "message" variable from the post request
// this is the data coming from the Android app
$message=$_POST["message"];
// specify the file where we will save the contents of the variable message
$filename="androidmessages.html";
// write (append) the data to the file
//file_put_contents($filename,$message."<br />",FILE_APPEND);
$fh = fopen("androidmessages.html", "wb");
fwrite($fh, $message."<br />");
fclose($fh);
// load the contents of the file to a variable
$androidmessages=file_get_contents($filename);
// display the contents of the variable (which has the contents of the file)
echo $androidmessages;
?>
您不应该在UI线程上执行网络IO。您需要使用AsyncTask或Thread在后台线程上执行网络事务。
您可以参考本教程以获得更多了解。
用try-catch块包围HttpClient，并将堆栈跟踪放在此处。。您可以在AsyncTask中执行所有Internet请求，该任务使用起来非常简单，不在UI线程中处理。