[android-developers] Re: Activity lifecycle and static variables ....
Statics are statics -- they are global to the process. So their value will last for the lifetime of the process, which is usually much longer than an individual activity instance. On Tue, Jul 14, 2009 at 12:52 PM, Richard Schilling richard.rootwirel...@gmail.com wrote: I just ran into a situation where it looks like a static variable reference is persisted across activity sessions. I didn't expect that because I thought that when an activity exits, it's de-referenced and garbage collected. I am wondering if anyone can shed some (more) light on when the VM eliminates object references for Activities and Services and in particular when static variables get reset to default values? Thanks. Richard Schilling Root Wireless -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: Activity lifecycle and static variables ....
Thanks Dianne. Very helpful indeed. For process lifetime, I don't think you're referring to the entire lifetime of an Activity as defined on the API reference page for Activity (http://developer.android.com/reference/android/app/ Activity.html): The entire lifetime of an activity happens between the first call to onCreate(Bundle) through to a single final call to onDestroy(). Rather, you're referring to a broader lifetime of the process that underlies the Activity correct? This would be the lifetime associated with android.os.Process I assume Richard Schilling Root Wireless On Jul 14, 1:23 pm, Dianne Hackborn hack...@android.com wrote: Statics are statics -- they are global to the process. So their value will last for the lifetime of the process, which is usually much longer than an individual activity instance. On Tue, Jul 14, 2009 at 12:52 PM, Richard Schilling richard.rootwirel...@gmail.com wrote: I just ran into a situation where it looks like a static variable reference is persisted across activity sessions. I didn't expect that because I thought that when an activity exits, it's de-referenced and garbage collected. I am wondering if anyone can shed some (more) light on when the VM eliminates object references for Activities and Services and in particular when static variables get reset to default values? Thanks. Richard Schilling Root Wireless -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: Activity lifecycle and static variables ....
Yeah, the process lifetime, which is outlined here: http://developer.android.com/guide/topics/fundamentals.html#proclife On Tue, Jul 14, 2009 at 1:38 PM, Richard Schilling richard.rootwirel...@gmail.com wrote: Thanks Dianne. Very helpful indeed. For process lifetime, I don't think you're referring to the entire lifetime of an Activity as defined on the API reference page for Activity (http://developer.android.com/reference/android/app/ Activity.htmlhttp://developer.android.com/reference/android/app/%0AActivity.html ): The entire lifetime of an activity happens between the first call to onCreate(Bundle) through to a single final call to onDestroy(). Rather, you're referring to a broader lifetime of the process that underlies the Activity correct? This would be the lifetime associated with android.os.Process I assume Richard Schilling Root Wireless On Jul 14, 1:23 pm, Dianne Hackborn hack...@android.com wrote: Statics are statics -- they are global to the process. So their value will last for the lifetime of the process, which is usually much longer than an individual activity instance. On Tue, Jul 14, 2009 at 12:52 PM, Richard Schilling richard.rootwirel...@gmail.com wrote: I just ran into a situation where it looks like a static variable reference is persisted across activity sessions. I didn't expect that because I thought that when an activity exits, it's de-referenced and garbage collected. I am wondering if anyone can shed some (more) light on when the VM eliminates object references for Activities and Services and in particular when static variables get reset to default values? Thanks. Richard Schilling Root Wireless -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: Activity lifecycle and static variables ....
Yes. I had read that, and I understand that the VM tries to stratify
processes depending on their function and keep my process alive as
long as possible. What I'm really interested in is detecting when the
the VM (re)-instantiated and garbage collects my Activity class, and
how that relates to the process identifier...
So, with this code, would procewssIDChanged ever be true? I know it's
a mundane question, but it tells me a lot about Android process
management
public IfWeirdAlWasAProgrammer extends Activity{
private static boolean newInstance = true;
private static int currentProcessId = -1;
private boolean processIDChanged = false; // non-static on purpose
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (newInstance){
Log.i(WeirdAlWasHere, Like a surgeon, cuttin' for the
very first time.);
newInstance = false;
currentProcessId = android.os.Process.myPid();
}
if (!newInstance (currentProcessId !=
android.os.Process.myPid()){
processIDChanged = true;
Log.i(WeirdAlWasHere, I lost on Jeapordy, baby!
O!);
}
}
}
Thanks again.
On Jul 14, 1:41 pm, Dianne Hackborn hack...@android.com wrote:
Yeah, the process lifetime, which is outlined here:
http://developer.android.com/guide/topics/fundamentals.html#proclife
On Tue, Jul 14, 2009 at 1:38 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
Thanks Dianne. Very helpful indeed.
For process lifetime, I don't think you're referring to the entire
lifetime of an Activity as defined on the API reference page for
Activity (http://developer.android.com/reference/android/app/
Activity.htmlhttp://developer.android.com/reference/android/app/%0AActivity.html
):
The entire lifetime of an activity happens between the first call to
onCreate(Bundle) through to a single final call to onDestroy().
Rather, you're referring to a broader lifetime of the process that
underlies the Activity correct? This would be the lifetime
associated with android.os.Process I assume
Richard Schilling
Root Wireless
On Jul 14, 1:23 pm, Dianne Hackborn hack...@android.com wrote:
Statics are statics -- they are global to the process. So their value
will
last for the lifetime of the process, which is usually much longer than
an
individual activity instance.
On Tue, Jul 14, 2009 at 12:52 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
I just ran into a situation where it looks like a static variable
reference is persisted across activity sessions. I didn't expect that
because I thought that when an activity exits, it's de-referenced and
garbage collected.
I am wondering if anyone can shed some (more) light on when the VM
eliminates object references for Activities and Services and in
particular when static variables get reset to default values?
Thanks.
Richard Schilling
Root Wireless
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time to
provide private support, and so won't reply to such e-mails. All such
questions should be posted on public forums, where I and others can see
and
answer them.
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time to
provide private support, and so won't reply to such e-mails. All such
questions should be posted on public forums, where I and others can see and
answer them.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google
Groups Android Developers group.
To post to this group, send email to android-developers@googlegroups.com
To unsubscribe from this group, send email to
android-developers-unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=en
-~--~~~~--~~--~--~---
[android-developers] Re: Activity lifecycle and static variables ....
No, it will never be true.
The VM doesn't manage processes at all. The system starts a process and
runs a VM inside of it when it needs to run any components of an
application. Unless you specify otherwise, all of your components run in
the same VM, in the same process, sharing all of the same statics.
There is really nothing special about this besides a normal operating
system. There are processes, these are managed by the kernel, and they run
some code. There is Dalvik, which is some code that can run in a process.
It can't hop your code into another process.
On Tue, Jul 14, 2009 at 2:59 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
Yes. I had read that, and I understand that the VM tries to stratify
processes depending on their function and keep my process alive as
long as possible. What I'm really interested in is detecting when the
the VM (re)-instantiated and garbage collects my Activity class, and
how that relates to the process identifier...
So, with this code, would procewssIDChanged ever be true? I know it's
a mundane question, but it tells me a lot about Android process
management
public IfWeirdAlWasAProgrammer extends Activity{
private static boolean newInstance = true;
private static int currentProcessId = -1;
private boolean processIDChanged = false; // non-static on purpose
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (newInstance){
Log.i(WeirdAlWasHere, Like a surgeon, cuttin' for the
very first time.);
newInstance = false;
currentProcessId = android.os.Process.myPid();
}
if (!newInstance (currentProcessId !=
android.os.Process.myPid()){
processIDChanged = true;
Log.i(WeirdAlWasHere, I lost on Jeapordy, baby!
O!);
}
}
}
Thanks again.
On Jul 14, 1:41 pm, Dianne Hackborn hack...@android.com wrote:
Yeah, the process lifetime, which is outlined here:
http://developer.android.com/guide/topics/fundamentals.html#proclife
On Tue, Jul 14, 2009 at 1:38 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
Thanks Dianne. Very helpful indeed.
For process lifetime, I don't think you're referring to the entire
lifetime of an Activity as defined on the API reference page for
Activity (http://developer.android.com/reference/android/app/
Activity.html
http://developer.android.com/reference/android/app/%0AActivity.html
):
The entire lifetime of an activity happens between the first call to
onCreate(Bundle) through to a single final call to onDestroy().
Rather, you're referring to a broader lifetime of the process that
underlies the Activity correct? This would be the lifetime
associated with android.os.Process I assume
Richard Schilling
Root Wireless
On Jul 14, 1:23 pm, Dianne Hackborn hack...@android.com wrote:
Statics are statics -- they are global to the process. So their
value
will
last for the lifetime of the process, which is usually much longer
than
an
individual activity instance.
On Tue, Jul 14, 2009 at 12:52 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
I just ran into a situation where it looks like a static variable
reference is persisted across activity sessions. I didn't expect
that
because I thought that when an activity exits, it's de-referenced
and
garbage collected.
I am wondering if anyone can shed some (more) light on when the VM
eliminates object references for Activities and Services and in
particular when static variables get reset to default values?
Thanks.
Richard Schilling
Root Wireless
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time
to
provide private support, and so won't reply to such e-mails. All
such
questions should be posted on public forums, where I and others can
see
and
answer them.
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time to
provide private support, and so won't reply to such e-mails. All such
questions should be posted on public forums, where I and others can see
and
answer them.
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time to
provide private support, and so won't reply to such e-mails. All such
questions should be posted on public forums, where I and others can see and
answer them.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google
Groups Android Developers group.
To post to this group, send email to
[android-developers] Re: Activity lifecycle and static variables ....
That affirms a lot for me. Thanks!
Richard Schilling
Root Wireless
On Jul 14, 4:35 pm, Dianne Hackborn hack...@android.com wrote:
No, it will never be true.
The VM doesn't manage processes at all. The system starts a process and
runs a VM inside of it when it needs to run any components of an
application. Unless you specify otherwise, all of your components run in
the same VM, in the same process, sharing all of the same statics.
There is really nothing special about this besides a normal operating
system. There are processes, these are managed by the kernel, and they run
some code. There is Dalvik, which is some code that can run in a process.
It can't hop your code into another process.
On Tue, Jul 14, 2009 at 2:59 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
Yes. I had read that, and I understand that the VM tries to stratify
processes depending on their function and keep my process alive as
long as possible. What I'm really interested in is detecting when the
the VM (re)-instantiated and garbage collects my Activity class, and
how that relates to the process identifier...
So, with this code, would procewssIDChanged ever be true? I know it's
a mundane question, but it tells me a lot about Android process
management
public IfWeirdAlWasAProgrammer extends Activity{
private static boolean newInstance = true;
private static int currentProcessId = -1;
private boolean processIDChanged = false; // non-static on purpose
�...@override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (newInstance){
Log.i(WeirdAlWasHere, Like a surgeon, cuttin' for the
very first time.);
newInstance = false;
currentProcessId = android.os.Process.myPid();
}
if (!newInstance (currentProcessId !=
android.os.Process.myPid()){
processIDChanged = true;
Log.i(WeirdAlWasHere, I lost on Jeapordy, baby!
O!);
}
}
}
Thanks again.
On Jul 14, 1:41 pm, Dianne Hackborn hack...@android.com wrote:
Yeah, the process lifetime, which is outlined here:
http://developer.android.com/guide/topics/fundamentals.html#proclife
On Tue, Jul 14, 2009 at 1:38 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
Thanks Dianne. Very helpful indeed.
For process lifetime, I don't think you're referring to the entire
lifetime of an Activity as defined on the API reference page for
Activity (http://developer.android.com/reference/android/app/
Activity.html
http://developer.android.com/reference/android/app/%0AActivity.html
):
The entire lifetime of an activity happens between the first call to
onCreate(Bundle) through to a single final call to onDestroy().
Rather, you're referring to a broader lifetime of the process that
underlies the Activity correct? This would be the lifetime
associated with android.os.Process I assume
Richard Schilling
Root Wireless
On Jul 14, 1:23 pm, Dianne Hackborn hack...@android.com wrote:
Statics are statics -- they are global to the process. So their
value
will
last for the lifetime of the process, which is usually much longer
than
an
individual activity instance.
On Tue, Jul 14, 2009 at 12:52 PM, Richard Schilling
richard.rootwirel...@gmail.com wrote:
I just ran into a situation where it looks like a static variable
reference is persisted across activity sessions. I didn't expect
that
because I thought that when an activity exits, it's de-referenced
and
garbage collected.
I am wondering if anyone can shed some (more) light on when the VM
eliminates object references for Activities and Services and in
particular when static variables get reset to default values?
Thanks.
Richard Schilling
Root Wireless
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time
to
provide private support, and so won't reply to such e-mails. All
such
questions should be posted on public forums, where I and others can
see
and
answer them.
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time to
provide private support, and so won't reply to such e-mails. All such
questions should be posted on public forums, where I and others can see
and
answer them.
--
Dianne Hackborn
Android framework engineer
hack...@android.com
Note: please don't send private questions to me, as I don't have time to
provide private support, and so won't reply to such e-mails. All such
questions should be posted on public forums, where I and others can see and
answer them.
