Hallo Android-Developer-Community,
ich habe folgendes Problem, und zwar möchte ich per button klick einen xml-file aus dem internet downloaden. dazu habe ich ein codebeispiel aus dem stackoverflow-forum gefunden. habe davor schon andere methoden verscuht. jedoch bekomme ich immer eine NetworkOnMainThreadException-Fehlermeldung. Ich weiß leider nicht mehr weiter bzw. was ich falsch mache und bitte um Hilfe und ratschläge.
Hier ist mein jetztiger Code:
MainActivity:
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import org.apache.http.util.ByteArrayBuffer;
import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity {
static final String URL = "http://www.overpass-api.de/api/xapi?*[bbox=7.1,51.2,7.2,51.3]";
TextView parameter;
Button start;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
parameter = (TextView)findViewById(R.id.textView_httpResult);
start = (Button)findViewById(R.id.btn_start);
}
public void getparam(View v) {
String fileName = "test";
String DownloadUrl = "http://www.overpass-api.de/api/xapi?*" +
"[key=value][bbox=11.58594,52.17035,11.63298,52.18888]";
try {
File root = android.os.Environment.getExternalStorageDirectory();
File dir = new File (root.getAbsolutePath() + "/xmls");
if(dir.exists()==false) {
dir.mkdirs();
}
URL url = new URL(DownloadUrl); //you can write here any link
File file = new File(dir, fileName);
long startTime = System.currentTimeMillis();
Log.d("DownloadManager", "download begining");
Log.d("DownloadManager", "download url:" + url);
Log.d("DownloadManager", "downloaded file name:" + fileName);
/* Open a connection to that URL. */
URLConnection ucon = url.openConnection();
/*
* Define InputStreams to read from the URLConnection.
*/
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
/*
* Read bytes to the Buffer until there is nothing more to read(-1).
*/
ByteArrayBuffer baf = new ByteArrayBuffer(5000);
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte) current);
}
/* Convert the Bytes read to a String. */
FileOutputStream fos = new FileOutputStream(file);
fos.write(baf.toByteArray());
fos.flush();
fos.close();
Log.d("DownloadManager", "download ready in" +
((System.currentTimeMillis() - startTime) / 1000) + " sec");
} catch (IOException e) {
Log.d("DownloadManager", "Error: " + e);
}
}
@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;
}
}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"
tools:context=".MainActivity" >
<Button
android:id="@+id/btn_start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:onClick="getparam"
android:text="GetOSMParameter" />
<TextView
android:id="@+id/textView_httpResult"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/btn_start"
android:layout_marginTop="48dp"
android:text=" "
android:textAppearance="?android:attr/textAppearanceSmall" />
</RelativeLayout>folgende persmissions sind festgelegt:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
Weiß jmd. einen rat? wäre für jede hilfe sehr dankbar. 
viele grüße
Es wird hier wohl niemand sein, der dir den kompletten Code vorkaut. Es gehört als Entwickler schon eigeninitiative dazu.
)