This is my first android app. I am posting the code I am using for HTTP connection(not mine, this is from one tutorial site). Problem is when I push the button for downloading text, it shows the progress dialog and the app force closes. I am posting the code.
package com.example.httpconnectsample;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import android.app.Activity;
import android.app.ProgressDialog;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
public class Httpconnectionsample extends Activity {
private Button getImageButton;
private Button getTextButton;
private ProgressDialog progressDialog;
private Bitmap bitmap = null;
private String text = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_httpconnectionsample);
getImageButton = (Button)findViewById(R.id.Button01);
getTextButton = (Button)findViewById(R.id.Button02);
getImageButton.setOnClickListener( new OnClickListener() {
@Override
public void onClick(View v) {
downloadImage("http://www.android.com/media/wallpaper /gif/android_logo.gif");
}
});
getTextButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
downloadText("http://xyz.com")
}
});
}
private void downloadImage(String urlStr) {
progressDialog = ProgressDialog.show(this, "", "Fetching Image...");
final String url = urlStr;
new Thread() {
public void run() {
InputStream in = null;
Message msg = Message.obtain();
msg.what = 1;
try {
in = openHttpConnection(url);
bitmap = BitmapFactory.decodeStream(in);
Bundle b = new Bundle();
b.putParcelable("bitmap", bitmap);
msg.setData(b);
in.close();
} catch (IOException e1) {
e1.printStackTrace();
}
messageHandler.sendMessage(msg);
}
}.start();
}
private void downloadText(String urlStr) {
progressDialog = ProgressDialog.show(this, "", "Fetching Text...");
final String url = urlStr;
new Thread () {
public void run() {
int BUFFER_SIZE = 2000;
InputStream in = null;
Message msg = Message.obtain();
msg.what=2;
try {
in = openHttpConnection(url);
InputStreamReader isr = new InputStreamReader(in);
int charRead;
text = "";
char[] inputBuffer = new char[BUFFER_SIZE];
while ((charRead = isr.read(inputBuffer))>0)
{
//---convert the chars to a String---
String readString =
String.copyValueOf(inputBuffer, 0, charRead);
text += readString;
inputBuffer = new char[BUFFER_SIZE];
}
Bundle b = new Bundle();
b.putString("text", text);
msg.setData(b);
in.close();
}catch (IOException e) {
e.printStackTrace();
}
messageHandler.sendMessage(msg);
}
}.start();
}
private InputStream openHttpConnection(String urlStr) {
InputStream in = null;
int resCode = -1;
try {
URL url = new URL(urlStr);
URLConnection urlConn = url.openConnection();
if (!(urlConn instanceof HttpURLConnection)) {
throw new IOException ("URL is not an Http URL");
}
HttpURLConnection httpConn = (HttpURLConnection)urlConn;
httpConn.setAllowUserInteraction(false);
httpConn.setInstanceFollowRedirects(true);
httpConn.setRequestMethod("GET");
httpConn.connect();
resCode = httpConn.getResponseCode();
if (resCode == HttpURLConnection.HTTP_OK) {
in = httpConn.getInputStream();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return in;
}
private Handler messageHandler = new Handler() {
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what) {
/*case 1:
ImageView img = (ImageView) findViewById(R.id.imageview01);
img.setImageBitmap((Bitmap)(msg.getData().getParcelable("bitmap")));
break; */
case 2:
TextView text = (TextView) findViewById(R.id.textview01);
text.setText(msg.getData().getString("text"));
break;
}
progressDialog.dismiss();
}
};
}
following is my XML
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/scrollView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<Button
android:id="@+id/Button02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="24dp"
android:text="Button" />
<Button
android:id="@+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="56dp"
android:text="Button" />
<TextView
android:id="@+id/textview01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="@+id/Button02"
android:layout_marginTop="39dp"
tools:context=".Httpconnectionsample" />
</RelativeLayout>
</ScrollView>
following is the Log:-
10-26 15:22:43.660: D/ddm-heap(23866): Got feature list request
10-26 15:22:48.930: W/System.err(23866): java.net.SocketException: Permission denied (maybe missing INTERNET permission)
10-26 15:22:48.940: W/System.err(23866): at org.apache.harmony.luni.platform.OSNetworkSystem.createStreamSocketImpl(Native Method)
10-26 15:22:48.945: W/System.err(23866): at org.apache.harmony.luni.platform.OSNetworkSystem.createStreamSocket(OSNetworkSystem.java:187)
10-26 15:22:48.945: W/System.err(23866): at org.apache.harmony.luni.net.PlainSocketImpl.create(PlainSocketImpl.java:266)
10-26 15:22:48.950: W/System.err(23866): at java.net.Socket.checkClosedAndCreate(Socket.java:889)
10-26 15:22:48.950: W/System.err(23866): at java.net.Socket.connect(Socket.java:1036)
10-26 15:22:48.950: W/System.err(23866): at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init> (HttpConnection.java:62)
10-26 15:22:48.950: W/System.err(23866): at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnectionManager$ConnectionPool.getHttpConnection(HttpConnectionManager.java:145)
10-26 15:22:48.950: W/System.err(23866): at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnectionManager.getConnection(HttpConnectionManager.java:67)
10-26 15:22:48.960: W/System.err(23866): at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnection.getHTTPConnection(HttpURLConnection.java:821)
10-26 15:22:48.960: W/System.err(23866): at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:807)
10-26 15:22:48.965: W/System.err(23866): at com.example.httpconnectsample.Httpconnectionsample.openHttpConnection(Httpconnectionsample.java:142)
10-26 15:22:48.965: W/System.err(23866): at com.example.httpconnectsample.Httpconnectionsample.access$3(Httpconnectionsample.java:126)
10-26 15:22:48.965: W/System.err(23866): at com.example.httpconnectsample.Httpconnectionsample$5.run(Httpconnectionsample.java:97)
10-26 15:22:48.965: W/dalvikvm(23866): threadid=15: thread exiting with uncaught exception (group=0x4001b180)
10-26 15:22:48.995: E/AndroidRuntime(23866): Uncaught handler: thread Thread-8 exiting due to uncaught exception
10-26 15:22:49.090: E/AndroidRuntime(23866): java.lang.NullPointerException
10-26 15:22:49.090: E/AndroidRuntime(23866): at java.io.Reader.<init>(Reader.java:65)
10-26 15:22:49.090: E/AndroidRuntime(23866): at java.io.InputStreamReader.<init>(InputStreamReader.java:65)
10-26 15:22:49.090: E/AndroidRuntime(23866): at com.example.httpconnectsample.Httpconnectionsample$5.run(Httpconnectionsample.java:99)
10-26 15:22:49.100: I/dalvikvm(23866): threadid=7: reacting to signal 3
10-26 15:22:49.115: I/dalvikvm(23866): Wrote stack trace to '/data/anr/traces.txt'
I tried searching for a fix but could not understand why this is happening. I just need to download text so at present I am ignoring download image part of this code. Also, I added
uses-permission android:name=”android.permission.INTERNET”
just above in manifest but still it is showing permission denied.
I’d be grateful for any help.
Add the INTERNET permission to your manifest file.
You have to add this line:
outside the application tag in your AndroidManifest.xml as shown below