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Android: Background Image Size (in Pixel) which Support All Devices
... ldpi (low) ~120dpi
mdpi (medium) ~160dpi
hdpi (high) ~240dpi
xhdpi (extra-high) ~320dpi
xxhdpi (extra-extra-high) ~480dpi
xxxhdpi (extra-extra-extra-high) ~640dpi
This corresponds to an xxhdpi screen. From here I could scale these 1080 x 1920 down by the (3:4:6:8:12) ratios above.
I ...
Android equivalent to NSNotificationCenter
...context, Intent intent) {
// Get extra data included in the Intent
String message = intent.getStringExtra("message");
Log.d("receiver", "Got message: " + message);
}
};
@Override
protected void onDestroy() {
// Unregister since the activity is about to be closed.
// This is somewh...
How to limit the maximum value of a numeric field in a Django model?
...
Here is the best solution if you want some extra flexibility and don't want to change your model field. Just add this custom validator:
#Imports
from django.core.exceptions import ValidationError
class validate_range_or_null(object):
compare = lambda self,...
Why does SIGPIPE exist?
...d.h>
# include <stdio.h>
# include <signal.h>
# include <string.h>
int writeCount = 0;
void sighandler(int sig) {
char buf1[30] ;
sprintf(buf1,"signal %d writeCount %d\n", sig, writeCount);
ssize_t leng = strlen(buf1);
write(2, buf1, leng);
_exit(1);
}
...
How to remove from a map while iterating it?
...r this pattern which is slightly clearer and simpler, at the expense of an extra variable:
for (auto it = m.cbegin(), next_it = it; it != m.cend(); it = next_it)
{
++next_it;
if (must_delete)
{
m.erase(it);
}
}
Advantages of this approach:
the for loop incrementor makes sense as an ...
Java - Convert integer to string [duplicate]
...
There are multiple ways:
String.valueOf(number) (my preference)
"" + number (I don't know how the compiler handles it, perhaps it is as efficient as the above)
Integer.toString(number)
...
Prevent contenteditable adding on ENTER - Chrome
... Doesn't work on Chrome. First time when you press enter at the end of the string, it adds a space. The second time it works though.
– user670839
Apr 15 at 19:24
add a comment...
Catch a thread's exception in the caller thread in Python
...rns to the main thread immediately when an exception is called
requires no extra user defined classes because it does not need:
an explicit Queue
to add an except else around your work thread
Source:
#!/usr/bin/env python3
import concurrent.futures
import time
def func_that_raises(do_raise)...
Design Patterns web based applications [closed]
... try {
Action action = ActionFactory.getAction(request);
String view = action.execute(request, response);
if (view.equals(request.getPathInfo().substring(1)) {
request.getRequestDispatcher("/WEB-INF/" + view + ".jsp").forward(request, response);
}
...
Maven Install on Mac OS X
...
Download Maven from its homepage
Follow the installation instructions:
Extract the distribution archive, i.e.apache-maven-3.3.9-bin.tar.gz to the directory you wish to install Maven 3.3.9. The subdirectory apache-maven-3.3.9 will be created from the archive.
Optional: Add the MAVEN_OPTS environm...