subclass

How can “default” values in overridden WinForm controls be prevented?

由 陌路散爱 提交于 2019-12-01 06:18:53
问题 I'm trying to learn and grasp what and how C# does things. I'm historically a Visual Foxpro (VFP) developer, and somewhat spoiled at the years of visual inheritance by creating my own baseline of user controls to be used application wide. In trying to learn the parallels in C#, I am stuck on something. Say I derive my own label control (control is subclass of label) defined with a font "Arial", 10 point. Then, on any form I add it to, the Designer will automatically pre-fill in some property

Subclass Python list to Validate New Items

由 做~自己de王妃 提交于 2019-12-01 05:27:27
问题 I want a python list which represents itself externally as an average of its internal list items, but otherwise behaves as a list. It should raise a TypeError if an item is added that can't be cast to a float. The part I'm stuck on is raising TypeError . It should be raised for invalid items added via any list method, like .append , .extend , += , setting by slice, etc. Is there a way to intercept new items added to the list and validate them? I tried re-validating the whole list in _

Django - Generic View Subclassed - url Parameters

由 空扰寡人 提交于 2019-12-01 04:48:20
问题 I need to display a detail page for a video with some other data. For that I use DetailView that I have overridden to add some variables to the context. Here are the code parts: #urlconf #... (r'viewtube/(?P<pk>\d+)$', VideoFileDetailView.as_view()), #... #view class VideoFileDetailView(DetailView): model = VideoFile def get_context_data(self, **kwargs): context = super(VideoFileDetailView, self).get_context_data(**kwargs) # context['rates'] = VideoRate.objects.filter(video=11, user=1) return

Casting subclasses extending the same original class

由 风格不统一 提交于 2019-12-01 04:45:41
问题 How can I cast two extends class like that in java? class B extends Object{ } class C extends Object{ } B b = new B(); C c = (C)b;//Cannot cast from B to C 回答1: You can't. Consider a slight rename: class Ford extends Car { } class Chevrolet extends Car { } Ford ford = new Ford(); Chevrolet chevrolet = (Chevrolet) ford; Both are, however, a Car so you can say Car car = ford; but not any more than that. 回答2: The closest you can come is to use interfaces class B extends Object implements Thing {

Subclassing a subclassed UIViewController that has a xib

由 ♀尐吖头ヾ 提交于 2019-12-01 04:01:53
I need to have a few UIViewControllers that look very similar yet have different behaviours, so I thought I'd make a general UIViewController subclass with a xib, then subclass it when I need to, for those different UIViewController's that look alike. I'm trying to achieve the following UIViewController subclass (that has a xib file associated) -> and being able to subclass it as many times as i'd like (without additional xib files for the children) what I've done so far : xib file represents a UIViewController with multiple UI Elements. I've set all the connections to file's owner @ xib file.

Where can I change the window my app uses from UIWindow to my own subclass “MyWindow” with storyboard?

由 时光毁灭记忆、已成空白 提交于 2019-12-01 02:40:51
I've got a universal project here with storyboard. I've created a subclass of UIWindow called MyWindow, and I need to load it instead of the default UIWindow. Prior to storyboard, I would simply go to the .XIB file in XCode and change the class for the main window to MyWindow. However, I'm unable to find any section where I can change this in storyboard. Does anyone know where I can do this? I need the main window to load MyWindow, not UIWindow. When using storyboards the application delegate and main window are no longer represented in Interface Builder. Instead, when your app starts, your

C# Make everything following public / private like in C++? [closed]

由 廉价感情. 提交于 2019-12-01 01:47:19
问题 It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 7 years ago . I recently started learning C#, but I have some background in C++. I was wondering how I would do something like class employee { public: .... ... methods ... .... private: .... ... private member variables ....

How can I get NSScrollView to respect a clipping path

由 走远了吗. 提交于 2019-12-01 01:35:25
I am trying to make a NSScrollView with clipped corners, similar to the Twitter app: I have a NSScrollView subclass which I added the following code: - (void)drawRect:(NSRect)dirtyRect { NSBezierPath *pcath = [NSBezierPath bezierPathWithRoundedRect:[self bounds] xRadius:kDefaultCornerRadius yRadius:kDefaultCornerRadius]; [path setClip]; [super drawRect:dirtyRect]; } I expected the content of the NSScrollView to have rounded corners, but it is not respecting the clipped path. How can I do this? UPDATE & CLARIFICATION I know how to make a custom NSScroller , I know how to make it transparent

Django Inheritance and Permalinks

由 為{幸葍}努か 提交于 2019-12-01 01:03:12
I'm creating a simple CMS in django, with multiple "modules" (each as a django app). I've set up the following models: class FooObject(models.Model): id = models.SlugField(primary_key=True) name = models.CharField(max_length=255) creator = models.ForeignKey(auth.models.User, editable=False, related_name="createdby") class FooPage(FooObject): content = models.TextField(blank=True, null=True) @models.permalink def get_absolute_url(self): return ('page', (), {'page_id':self.id} class FooSubitem(FooObject): parent = models.ForeignKey(FooPage, related_name='subitems') In each of the modules, I

No Matching Function Call to Base class

由 大兔子大兔子 提交于 2019-11-30 23:18:18
Here I am trying to make a subclass of the base class, Airplane. In my main code I haven't tried to use either constructor yet as I am just trying to make sure I can make the subclass Fighter to properly work. The exact error its giving me is no matching function for call to 'Airplane:Airplane()' And says it pertains to this line of code in the Fighter.cpp Fighter::Fighter(int engi, int seat, string description) Fighter.cpp #include "Fighter.h" Fighter::Fighter(int engin, int seat, string description) { fNumEngines = engi; fNumSeats = seat; rangeAndSpeedDesc = description; } Fighter.h #include
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