大约有 40,000 项符合查询结果（耗时：0.0872秒） [XML]
What is Lazy Loading?
...:
...
@property
def total(self):
if not hasattr(self, "_total"):
self._total = self.quantity \
+ sum(bi.quantity for bi in self.borroweditem_set.all())
return self._total
Basically, I have an Item class which represents an item in our inven...
Django migration strategy for renaming a model and relationship fields
...ration(migrations.Migration):
dependencies = [
('myapp', '0001_initial'),
]
operations = [
migrations.RenameModel('Foo', 'Bar'),
migrations.RenameField('AnotherModel', 'foo', 'bar'),
migrations.RenameField('YetAnotherModel', 'foo', 'bar')
]
You ma...
Scala: write string to file in one statement
....write(Paths.get("file.txt"), "file contents".getBytes(StandardCharsets.UTF_8))
I think this is by far the simplest and easiest and most idiomatic way, and it does not need any dependencies sans Java itself.
share
...
`Apache` `localhost/~username/` not working
...
Looks like you need to uncomment the following:
#LoadModule userdir_module libexec/apache2/mod_userdir.so
and
#Include /private/etc/apache2/extra/httpd-userdir.conf
Then in httpd-userdir.conf you may need to uncomment:
#Include /private/etc/apache2/users/*.conf
Lastly you would need ...
Splitting templated C++ classes into .hpp/.cpp files--is it possible?
...
You can do it in this way
// xyz.h
#ifndef _XYZ_
#define _XYZ_
template <typename XYZTYPE>
class XYZ {
//Class members declaration
};
#include "xyz.cpp"
#endif
//xyz.cpp
#ifdef _XYZ_
//Class definition goes here
#endif
This has been discussed in Daniweb
...
How to set HttpResponse timeout for Android in Java
...t(httpParameters, timeoutConnection);
// Set the default socket timeout (SO_TIMEOUT)
// in milliseconds which is the timeout for waiting for data.
int timeoutSocket = 5000;
HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
DefaultHttpClient httpClient = new DefaultHttpClient(httpPa...
Is there a way to programmatically scroll a scroll view to a specific edit text?
...
private final void focusOnView(){
your_scrollview.post(new Runnable() {
@Override
public void run() {
your_scrollview.scrollTo(0, your_EditBox.getBottom());
}
});
}
...
How to add a button to UINavigationBar?
...= CGRectMake(0, 0, 32, 32);
[button setImage:[UIImage imageNamed:@"settings_b.png"] forState:UIControlStateNormal];
[button addTarget:self action:@selector(openView) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *barButton=[[UIBarButtonItem alloc] init];
[barButton setCustomView:bu...
Cleaner way to do a null check in C#? [duplicate]
...n(string[] args)
{
Person nullPerson = null;
var isNull_0 = nullPerson.IsNull(p => p.contact.address.city);
var isNull_1 = new Person().IsNull(p => p.contact.address.city);
var isNull_2 = new Person { contact = new Contact() }.IsNull(p => p.contact.addres...
Is it possible to change only the alpha of a rgba background colour on hover?
...solute on the <div> tag
Option 1: ::before psuedo-element:
.before_method{
position:relative;
}
.before_method:before{
display:block;
content:" ";
position:absolute;
z-index:-1;
background:rgb(18, 176, 41);
top:0;
left:0;
right:0;
bottom:0;
opacity:0.5;
}
.before_metho...