Re: waiting threads until it gets value
On Sun, 27 Dec 2009, focode wrote:
checking gprs data takes some time , in the mean time
"switchDisplayable(null, getMainMenu());" is called , while the process
of checking gprs continues, and when the application founds that gprs is
not subscribed , it takes appropriate action , (and exits the program ).
what is required is .. until and unless the checking of gprs is verified
, the program should not take any further action , and should wait their
itself , i think use of "wait" function should solve my problem , can
any one guied me where to put "wait" to solve this problem, i shall be
highly thankfull.
It's not clear to me what you want. Is it that the application should
first display the main menu, and then if later on the GPRS verification
fails, it should switch to the error message and quit? In that case, you
don't necessarily need a wait - the code above will work, although it
could be even simpler:
public void check_gprs() {
new Thread(this).start();
switchDisplayable(null, getMainMenu());
}
public void run() {
// try to download URL
if (text.equals("error")) switchDisplayable(null, getPacketdatamissing());
}
That's all you need.
If you want the program to display the main menu and then wait until the
verification has finished, then you have a couple of options. The simplest
is actually to use join, not wait - join waits for another thread to
finish:
public void check_gprs() {
Thread t = new Thread(this);
t.start();
switchDisplayable(null, getMainMenu());
t.join();
}
If you want a real wait, it's like this:
private boolean verificationComplete = false;
public void check_gprs() {
new Thread(this).start();
switchDisplayable(null, getMainMenu());
synchronized (this) {
// you need to decide what to do with InterruptedException here
while (!verificationComplete) wait();
}
}
public void run() {
// try to download URL
if (text.equals("error")) switchDisplayable(null, getPacketdatamissing());
synchronized (this) {
verificationComplete = true;
notifyAll();
}
}
tom
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