The page I am working on has a javascript function executed to print parts of the page. For some reason, printing in Safari, causes the window to somehow update. I say somehow, because it does not really refresh as in reload the page, but rather it starts the "rendering" of the page from start, i.e. scroll to top, flash animations start from 0, and so forth. The effect is reproduced by this fiddle: http://jsfiddle.net/fYmnB/ Clicking the print button and finishing or cancelling a print in Safari causes the screen to "go white" for a sec, which in my real website manifests itself as something "like" a reload. While running print button with, let's say, Firefox, just opens and closes the print dialogue without affecting the fiddle page in any way. Is there something with my way of calling the browsers print method that causes this, or how can it be explained - and preferably, avoided? P.S.: On my real site the same occurs with Chrome. In the ex
Afaik, sending ICMP ECHO requests needs root (i.e. the app that does it needs to be setuid) - and that's not currently possible in "stock" Android (hell, even the InetAddress#isReachable() method in Android is a joke that doesn't work according to spec).
ReplyDeleteA very basic example using /usr/bin/ping & Process - reading the ping results, using an AsyncTask:
public class PingActivity extends Activity {
PingTask mTask;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
@Override
protected void onResume() {
super.onResume();
mTask = new PingTask();
// Ping the host "android.com"
mTask.execute("android.com");
}
@Override
protected void onPause() {
super.onPause();
mTask.stop();
}
class PingTask extends AsyncTask<String, Void, Void> {
PipedOutputStream mPOut;
PipedInputStream mPIn;
LineNumberReader mReader;
Process mProcess;
TextView mText = (TextView) findViewById(R.id.text);
@Override
protected void onPreExecute() {
mPOut = new PipedOutputStream();
try {
mPIn = new PipedInputStream(mPOut);
mReader = new LineNumberReader(new InputStreamReader(mPIn));
} catch (IOException e) {
cancel(true);
}
}
public void stop() {
Process p = mProcess;
if (p != null) {
p.destroy();
}
cancel(true);
}
@Override
protected Void doInBackground(String... params) {
try {
mProcess = new ProcessBuilder()
.command("/system/bin/ping", params[0])
.redirectErrorStream(true)
.start();
try {
InputStream in = mProcess.getInputStream();
OutputStream out = mProcess.getOutputStream();
byte[] buffer = new byte[1024];
int count;
// in -> buffer -> mPOut -> mReader -> 1 line of ping information to parse
while ((count = in.read(buffer)) != -1) {
mPOut.write(buffer, 0, count);
publishProgress();
}
out.close();
in.close();
mPOut.close();
mPIn.close();
} finally {
mProcess.destroy();
mProcess = null;
}
} catch (IOException e) {
}
return null;
}
@Override
protected void onProgressUpdate(Void... values) {
try {
// Is a line ready to read from the "ping" command?
while (mReader.ready()) {
// This just displays the output, you should typically parse it I guess.
mText.setText(mReader.readLine());
}
} catch (IOException t) {
}
}
}
}