How to replace ClutterTexture with key action? - c

I want to change the background texture of a Gobject clutter actor whenever it is highlighted. Is there any way i can replace the texture during runtime ?

you can use the clutter_texture_set_* family of functions, like:
clutter_texture_set_from_file
clutter_texture_set_from_rgb_data
clutter_texture_set_area_from_rgb_data
all documented here: http://developer.gnome.org/clutter/stable/ClutterTexture.html

Related

SDL_CreateRenderer() vs SDL_CreateSoftwareRenderer()

Does a renderer created with SDL_CreateSoftwareRenderer() behave any differently than one created with SDL_CreateRenderer() using the SDL_RENDERER_SOFTWARE flag?
There are differences on how these two operate, or even their intended use. SDL_CreateSoftwareRenderer creates software renderer drawing to given surface. There is no requirement for this surface to be window surface, you can draw to backbuffer, convert it to texture and feed the result to d3d or opengl renderer.
SDL_CreateRenderer creates renderer for a given window, meaning it is supposed to draw to that window - with some checks, like opengl or vulkan requires window to be created with specific flags. It goes through list of available rendering backends and tries to find the one that matches your flags the best. Eventually if it decides to use software renderer (either nothing else is supported or software is explicitly requested, although there is more than one way to do so - see the last paragraph) it calls more-or-less SDL_CreateSoftwareRenderer(SDL_GetWindowSurface(window)) (not exactly so, but if you'll trace the code it is the same).
flags in SDL_CreateRenderer are not absolute; if a hint says to use direct3d or opengl, your SDL_RENDERER_SOFTWARE will be ignored. SDL_CreateSoftwareRenderer is always software.
Nope! They should behave the same.
SDL2 has quite a list of convenience functions which are equivalent to simply calling another function with a specific set of arguments. For instance, looking at the API listing by name, you'll find that the SDL_LogMessage () function is matched with a variety of other functions that implicitly specify the priority field, like SDL_LogVerbose () or SDL_LogError ().
To some extent, in addition to providing ease-of-use, these combined convenience functions help provide brevity to code while still maintaining clarity. As such, I would advise and advocate for their use when possible!

Track C variable doxygen

New to Doxygen and wondering can it be used to draw a graph showing what functions use a given global variable. I have been able to get call/caller graphs working for functions and want to do something similar for a hand full of variables.
REFERENCED_BY_RELATION = YES: In a Variable description it documents all functions which have used the variable and generates a hyperlink to these functions in the code. In the function documentation, this documents all functions being used in that particular function and also generates a hyperlink to the actual code.
REFERENCES_RELATION = YES: In a function documentation, this documents all functions that have called the function being described and also generates a hyperlink tot he code.
Although this is not a graphical solution (which would be way better), this is something one can definitely work with.

Creating a GroupBox with _createChildControlImpl()

I tryed to create a group box with the _createChildControlImpl()-Methode but the layout looks like crap as you can see her http://tinyurl.com/odzgy3v
But when I implement it without _createChildControlImpl() it works fine: http://tinyurl.com/kwzvdm2
Could anybody please tell me what's the reason for this? Thanks in advance!
Have a look at your browser console - there is already a hint.
When you introduce child controls qooxdoo can't reuse the former default appearance of widgets because the appearance id changed (from "groupbox" to "widget/groupBox"). So you have to add your own appearance theme (which can simply forward by using an alias):
qx.Theme.define("test.myAwesomeTheme", {
extend : playground.theme.Appearance,
appearances :
{
"widget/groupBox" : "groupbox",
}
});
qx.theme.manager.Appearance.getInstance().setTheme(test.myAwesomeTheme);
I'm extending playground.theme.Appearance here which extends qx.theme.indigo.Appearance which again extends qx.theme.simple.Appearance. And their you have the groubox definition we are forwarding to.
Here is the complete playground sample.
You are supposed to implement _createChildControl, but not call it directly. Instead call getChildControl in your constructor and let it call _createChildControl, if needed, since it is also caching the result.
GroupBox seems to be a bad fit for what you want - it seems to assume identically sized and shaped elements inside its frame sub-widget, when filled from within the implementation of _createChildControl().
Use another Composite() inside the main container instead, add "Registration" as yet another child control of type label as the first child of the custom widget, and things will look much better (although not identical).
Quick and sloppy proof of concept: http://tinyurl.com/m7ykhta

How to declare, same webelement with different ids using Findby?

For instance, is it possible to define:
#FindBy(By.id("id1") OR By.id("form1:id1"))
public WebElement button
So that button having either "id1" or "form1:id1" should work fine?
You can use the #FindBys annotation, the syntax is:
#FindBys({#FindBy(id = "foo"),
#FindBy(className = "bar")})
The JavaDoc describes it here:
http://selenium.googlecode.com/git/docs/api/java/org/openqa/selenium/support/FindBys.html
Well,
use whathever you want, as long as it works
Personally I would use #FindBy(By.id("id1")) but it is just point of choice.
Also, there is no value added in referring same element twice with two different methods. It will only cause mess in your code
EDIT
As I understood your comment, there is element on the page which constantly changes its ID. If you need to refer to such elements, try using xPath See for example this xpath tutorial
The idea is that you will point to some place in the DOM rather than to specific ID
Use Xpath or CSS selector to do that. Or Java to store the ID name in String and then you can fill it to your Id.

UICollectionViewLayout Examples

Can anybody point me in the right direction to how I could use UICollectionViewLayout to create an interface similar to the Pinterest column layout?
I tried searching online, but it looks like there are not many examples out there yet.
The 1000memories "Quilt" view is pinterest-like and open source: http://blog.1000memories.com/168-opensourcing-quilt, and you can dig through that to see how it works.
If you're looking for a more conceptual overview, here's the basic idea of what you're going to want to do. The easiest thing by far, if you just need a Pinterest-style layout, is to subclass UICollectionViewFlowLayout. You get a lot of layout help from this class, and Pinterest style is within its capabilities. You only need to override one method.
Set up a normal UICollectionView using UICollectionViewFlow layout. A quick way to do this is:
Drag a UIViewController onto a storyboard, drop a UICollectionView on that. Set the classes to match your custom classes, etc. You can use a delegate and create a delegate class here but strictly speaking that is not necessary to achieve JUST the Pinterest flow layout (you will almost definitely want to break the selection responsibility stuff into a delegate class in reality though).
Stub out a data source. Implementing the data source protocol for UICollectionView (http://developer.apple.com/library/ios/#documentation/uikit/reference/UICollectionViewDataSource_protocol/Reference/Reference.html) is trivially simple. Make sure you set a reuse identifier on your UICollectionViewCell. You need:
(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
just return 1 for now;
(NSInteteger)collectionView:numberOfItemsInSection:
hardcode a number for now, make it 20.
– (UICollectionViewCell *)collectionView:cellForItemAtIndexPath:
This is one of the places where subclassing the flow layout's gonna do you a favor. All you really need to do here is call dequeueReusableCellWithReuseIdentifier:forIndexPath: with the index path. If you added a UIImageView or some labels to the cell, this would be a great place to actually assign the image, text, etc.
In the viewController's viewDidLoad instantiate a UICollectionViewFlowLayout and set the UICollectionView's datasource to yours and layout to flowlayout. Remember, this class is a subclass of UICollectionViewViewController.
self.collectionView.dataSource = [[YourDataSource alloc] init];
self.collectionView.collectionViewLayout = [[UICollectionViewFlowLayout alloc] init];
Ok. At this point you should be able to run your app and see some stuff on the screen. This is a whirlwind overview. If you need more details about how to set up ViewControllers and so on there's tons of stuff available about that.
Now comes the important part, Pinterest-izing the flow layout.
First, add a new class that is a subclass of UIViewControllerFlowLayout. Change your ViewController's viewDidLoad to instantiate this class and assign as the UICollectionView's collectionViewLayout.
The method you are going to need to implement is - (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect.
Here's the thing: The superclass is going to do almost all the work for you. Your code is going to look something like this:
- (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect
{
NSArray *attributes = [super layoutAttributesForElementsInRect:rect];
[attributes enumerateObjectsUsingBlock:^(id attr, NSUInteger idx, BOOL *stop) {
float newYCoord = [calculationMethodYouHaveToWriteFor:attr.frame];
attr.frame = CGRectMake(attr.frame.origin.x, newYCoord, attr.size.width, attr.size.height];
}];
}
Pinterest uses fixed-width columns, all you need to do in your calculation method is figure out what column you are in (`attr.origin.x / _columnWidth), and look up the total height in that column from the ivar you've been saving it in. Don't forget to add it to the new object's height and save it back for the next pass.
The flow layout superclass handles: making cells, determining which cells are visible, figuring out the contents size, figuring out the arrangement of the rows in the x direction, assigning index paths to cells. Lots of junk. And overriding that one method lets you fiddle with the y-pos to your heart's desire.
Heres two from github
https://github.com/jayslu/JSPintDemo
https://github.com/chiahsien/UICollectionViewWaterfallLayout
I've used a modified version of Waterfall in a project now, and I'm investigating JSPint now.
I have created a custom uicollectionviewlayout which is used in my personal project. Here is the link. Hope it helps.
https://github.com/johnny0614/YJZAlbumCollectionViewLayout
You can get anything you want from here:
https://github.com/ParsifalC/CPCollectionViewKit
For example(Both these two layouts are custom UICollectionViewLayout):

Resources