Java Android 4.2上的HttpClient.execute(HttpPost)错误
我跟随这个网站尝试使用android应用程序连接PHP服务器来获取消息 GetServerMessage.javaJava Android 4.2上的HttpClient.execute(HttpPost)错误,java,android,Java,Android,我跟随这个网站尝试使用android应用程序连接PHP服务器来获取消息 GetServerMessage.java import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.cl
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
public class GetServerMessage {
public String stringQuery(String url){
try
{
HttpClient httpclient = new DefaultHttpClient();
HttpPost method = new HttpPost(url);
HttpResponse response = httpclient.execute(method);
HttpEntity entity = response.getEntity();
if(entity != null){
return EntityUtils.toString(entity);
}
else{
return "No string.";
}
}
catch(Exception e){
return "Network problem";
}
}
}
GetPhpServerMessageDemoActivity.java
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class GetPhpServerMessageDemoActivity extends Activity {
/** Called when the activity is first created. */
private TextView textView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textView = (TextView)findViewById(R.id.text_view);
GetServerMessage message = new GetServerMessage();
String msg = message.stringQuery("http://192.168.1.88/androidtesting.php");
textView.setText("Server message is "+msg);
}
}
我试着从那个网站下载Android应用程序项目并在我的手机上运行,这是成功的。
但是当我启动一个新项目(Minimuim-required-SDK:API8,Target-SDK:API17,Compile-with:API17)并复制这两个java代码时。我已经添加了权限
android.permission.INTERNET
,所以我不知道问题出在哪里,我只知道当运行HttpResponse response=httpclient.execute(方法)时
出现错误并返回字符串“Network problem”。正如Sotirios Delimanolis所说,您需要在一个单独的线程上运行长时间运行的任务,如网络调用。可能就是这样。您正在ui线程上运行与网络相关的操作。您将获得networkonmainthreadeception
post蜂巢
使用线程
或异步任务
调用异步任务
new TheTask().execute("http://192.168.1.88/androidtesting.php");
异步任务
是不是NetworkOnMain
?
class TheTask extends AsyncTask<String,String,String>
{
@Override
protected String onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
// update textview here
textView.setText("Server message is "+result);
}
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
}
@Override
protected String doInBackground(String... params) {
try
{
HttpClient httpclient = new DefaultHttpClient();
HttpPost method = new HttpPost(params[0]);
HttpResponse response = httpclient.execute(method);
HttpEntity entity = response.getEntity();
if(entity != null){
return EntityUtils.toString(entity);
}
else{
return "No string.";
}
}
catch(Exception e){
return "Network problem";
}
}
}