let's say I have hwnd handle and would like to add some GUI controls in memory. I also receive all user input via events.
So, is it possible to use wxwidgets to add a user interface to an image which will be drawn onto the a Window ( using such hwnd handle ). If so, does wxwidget have some facilities to keep track of state of the GUI?
I'm new to wxwidgets and so please excuse my general questions.
Many thanks,
Christian
The only way to add GUI controls to an image, is to draw them yourself. The only way to do that, would be to create an image GUI element, and position the other GUI elements relative to the image element. However, this will not do double-buffering of the UI like you want to do, it doesn't actually draw the UI elements in the image, just places them on top of the image.
Related
I am trying to place some overlay text over a wxPanel.
I have several panels with completely different Content but I want to place this overlay text over all of these panels in the top right Corner of the panel.
I am restricted to wxWidgets 2.8.12..
Do you see any way to achieve this behaviour?
Edit:
Here a bit more detailed Version of what I am trying to do:
I have a Layout that consists of e.g. 5 containers and each container can contain a module. A module can be either wxPanels that contain Plain text or Input controls or for example a OpenGL canvas or an Image or something else.
Because I have much content and it does not fit on a single page I want to make the modules inside a Container exchangeable. It would be also nice if the user is able to perform this action only by using its keyboard. E.g. if he presses the key "3" the content of the third container has to be switched.
To handle these shortcuts isn't a problem. However I need to signalize to the user the identifier / hotkey of the containers.
I could do this by placing a additional headline above each container, but I want to waste as little space as possible on the gui.
I also could draw directly to the modules content, but I would have to do this for every module and every module is designed in a different way (images, multi column, opengl, ...) and maybe even by different persons.
So I am looking for a simple solution to indicate the number of these containers that does not consume that much space.
Thanks for your help
You can use a wxWindowDC to draw anywhere on the window, even on child windows. However anything you draw will be painted over whenever the windows or controls repaint themselves. You can draw your overlay in an UpdateUI event handler to minimize this. I have used this approach with success on Windows with wxWidgets 2.8.12. Not sure if it works with OpenGL though.
I've been looking around for awhile about how to produce buttons using Direct2D and DirectWrite with no luck. I'm comfortable with shapes, text and that jazz. However, it suddenly occurred to me I might be looking about it in the wrong way.
Take the sentence:
you draw your controls and content for your app using the Direct2D and
DirectWrite APIs, handling all the input events directly.
I'm now thinking this means that instead of being able to quickly produce a fully functional button as I would using XAML. I would draw the button, manually check the location of the mouse on click, whether it's within the button boundaries and then handle the event? Similar method for hovering without the click.
Is this the kind of method required when using Direct2D and DirectWrite?
I haven't any experience with DirectX, but in OpenGL I build my buttons from scratch. Assuming you have animated sprites implemented, your buttons are essentially sprites that play certain animations in response to being clicked, hovered over, etc., and which you can register callbacks with. In my 2D engine, I have a class called UiButton, which inherits Sprite, and listens for various UI events. It gets more complicated when you want to handle keyboard navigation (arrow keys + enter to select) as you have to think about how the buttons are connected and which of them has focus at any given moment.
Here is my implementation for reference:
Headers: https://github.com/RobJinman/dodge/tree/master/Dodge/include/dodge/ui
Source: https://github.com/RobJinman/dodge/tree/master/Dodge/src/ui
If you're not prepared to roll your own, Googling "direct2d gui framework" seems to bring up some promising results.
Sorry I can't be of more help.
Yes, to draw a UI Button with Direct2D, you need to handle everything yourself, why? Direct2D is a 2D graphics API, not controls library. you need to draw the layout of your button, and handle the message of your button(such as click, mouse hover...), you lost lots of convenient and that's time-consuming, but the most important thing is: you can control it by yourself!
Direct2D is a graphics library. UI controls like, Text-selection, Textbox, and Buttons is not a part of it. However the benefits of using Direct2D and DirectWrite is we can implement our own UI controls, and having a full control of it.
Please also see: ID2D1Geometry::FillsContainsPoint() for hit-testing task.
I'm wondering if there is a way to make Qt widgets within a QMainWindow widget stretch and scale as the size of the main window is stretched and shrunk. Basically, I'd like the entire window and it's contents to have the same appearance except for size:
At the only way I can think to accomplish this is to get the size of the main window, do the math for every single widget, and reset their sizes any time the main window size is changed, but I'm thinking there's an easier way.
I like this video tutorial on youtube. I'll help you create a layout using QLayout classes. If you use QtCreator/Designer, you can also take a look at the auto-generated ui_MainWindow.XXX file that will clue you in on how it uses some of the UI classes.
As always, QtCreator/Designer has a bunch of hints and tips so you should be able to dig up from the documentation that's embedded in the application.
I have a general question on how to develop an image viewer plugin with Firebreath. For that, I would like to incorporate a GUI framework, like wxwidget or Qt. The GUI would be used to to fire up some dialogs, adding a toolbar on top, or to open context menus with right clicking an image.
As far as I understand I have a hwnd handle and so I can draw onto a window. I also understand that I have various events I can react on, like mouse button clicks or keyboard strokes. But it fails me how I would add graphical menus, buttons, etc. I know I could use html around the window but that's not the route I like to take.
For instance, does it makes sense to render an user interface offline (in memory) onto an image and then keep somehow track of the state internally?
Has anyone done such thing? Or can anyone give me some insight on how to accomplish adding a user interface.
Assuming you only care about windows and assuming that you don't mind using a windowed plugin, which is the easiest (but no HTML elements can float over the plugin), it should be no different than creating a GUI in any other windows application.
You are given a window that shows up with the AttachedEvent; when DetachedEvent is fired you need to stop using the window. Many people create a child window inside that parent window and use that for all their actual real code which makes it a little easier to use one of those other abstractions, but that's basically all there is to it. I don't know specifically how you'd do it with QT or wxwidget but you'd create a child window of that HWND that you are given and have the abstraction do your thing for you.
As to whether or not it would be rendering things offscreen, etc, I have no idea; that would totally depend on the window system. There is no reason that I know of that you would need to do that, and most things just draw directly to the HWND, but there are a zillion different ways you could do it. It looks to me like what you really need is to understand how drawing in Windows actually works.
I hope that helps
How Would I go about placing text on the windows desktop? I've been told that GetDesktopWindow() is what I need but I need an example.
I'm assuming your ultimate goal is displaying some sort of status information on the desktop.
You will have to do either:
Inject a DLL into Explorer's process and subclass the desktop window (the SysListView32 at the bottom of the Progman window's hierarchy) to paint your text directly onto it.
Create a nonactivatable window whose background is painted using PaintDesktop and paint your text on it.
First solution is the most intrusive, and quite hard to code, so I would not recommend it.
Second solution allows the most flexibility. No "undocumented" or reliance on a specific implementation of Explorer, or even of just having Explorer as a shell.
In order to prevent a window from being brought to the top when clicked, you can use the extended window style WS_EX_NOACTIVATE on Windows 2000 and up. On downlevel systems, you can handle the WM_MOUSEACTIVATE message and return MA_NOACTIVATE.
You can get away with the PaintDesktop call if you need true transparency by using layered windows, but the concept stays the same. I wrote another answer detailing how to properly do layered windows with alpha using GDI+.
Why not just draw the text in the desktop wallpaper image file?
This solution would be feasible if you don't have to update the information too often and if you have a wallpaper image.
One can easily use CImage class to load the wallpaper image, CImage::GetDC() to obtain a device context to draw into, then save the new image, and finally update the desktop wallpaper to the new image.
i haven't tried but i assume you could do the following:
use GetDesktopWindow to retrieve the handle of the desktop window
use SetWindowLong to point the windows message handler to your own procedure
in your proc, process the WM_PAINT message (or whatever) and draw what you need.
in your proc, call the original message handler (as returned by SetWindowLong).
not 100% sure it will work, but seems like it should as this is the normal way to subclass a window.
-don
If your intent is to produce something like the Sidebar, you probably just want to create one or more layered windows. That will also allow you to process mouse clicks and other normal sources of input, and if you supply the alpha channel information, Windows will make sure that your window is drawn properly at all times. If you don't want the window to be interactive, use appropriate styles (such as WS_EX_NOACTIVATE) like Koro suggests.