I have a Window object which contains only a grid. I want to use Gtk::Builder to get a pointer to the grid, and then use some Gtk::Box's Gtk::Box->pack_end() to add the grid to it many times (with manipulated contents each time).
Though each time that pack_end() is called I get:
gtk_box_pack: assertion 'gtk_widget_get_parent (child) == NULL' failed in my terminal and nothing gets added to the box.
What should I do?
Thanks
* EDIT:
Goal:
I want entries of a DB table to be put into a fancy widget for each record, though all the records being shown vertically one after the other. I thought I can create the fancy widget as a window in Glade and use Gtk::Builder to get a pointer to it. So in the fancy's Glade file I have a window containing a grid that has my custom appearance. I get the above error when I try to add the pointer to the fancy *grid*, to the visible window's Box. I hope I'm clear.
Here's the solution to gtk_box_pack: assertion 'gtk_widget_get_parent (child) == NULL' failed:
All that needs to be done at the first place is that you should draw the widgets WITHOUT a window, so when loaded with builder, it won't have a parent and thus the assersion succeeds.
Though here's another point: When I add the first instance of the grid to the Box, the second one results in the same error again. After a couple of trials and errors I realized that in each interation you should use Gtk::Builder::create_from_file() to create a new parent-less instance of the grid to be able to use, and this way it works.
There has to be a great difference in performance, in case number of records is gonna be big, but Gtk::Widget's copy constructor is private and direct copying is not possible, and since it wasn't my main obsession I didn't insist on resolving this "performance" issue.
Related
I searched on the forum and I don't find a solution for my issue. So I hope you can help me :)
I work on a personal project for SFC designing (Sequential functional chart) and I'm working with visual studio in SDI(I'm using MFC library). If you see the "design" of an SFC you can see the different elements needed to compose this. So you can find Step, Transition, and more. If I take a step for explaining my issue, after double click on the step a popup dialog is opened with the elements to define this step (actions on this step, and more). The issue is here, I can't see two or more step elements at the same time. I want to reuse the existing concept on other software, see this.
Step close
Step open
Dialog to add
My question is, how I can implement a dialog with my graphic element in mainframe (In this case, a step)? I don't know how I can insert a dialog with my element, I think I need to use CFormView, but I don't know.
This dialog needs to be resizable and reduce directly by the step graphic.
any idea?
Thank you in advance! Sorry for my English ..
Sorry, I think my request is not clear .. (Thank you for your answer)
The context, it's an SDI application with the Document/View architecture. Actually the view is derived from CScrollView.
So, in the document class, you have the different lists of components for make SFC (Steps, transitions and symbols ..). I'm working today on Step element.
The user inserts a new step, the step is draw on the view like this :
enter image description here
And now the user want change the events on this Step, for this after double click on the step the events editor is opened at right of step draw, like this :
enter image description here
For this, I've created a new dialog resource and create the class by wizard in CForwView derived class. In step attribute, you can find one instance of this derived class (The derived class of dialog).
But this doesn't work correctly, I think my method is bad. At the first try, I have sent the pointer of the current document to the "CFormView::Create" function for having the "Save" button active with the focus on the FormView. But after destroying the step, the instance of FormView is destroyed and the document with the instance of formview ...
No problem, you can use "Create" within CCreateContext a null pointer. But with the document or without I have a lot of problems (graphic design not correct in FormView, regularly (not systematic I have assert fail on Proc exchange (for differents reason)). But the "concept" is good, the editor follows the draw if I scroll, I can open or close the editor at any time and on any elements.
For the old capture, it's my SFC designer "model". My application is a complement to this application, so I want a similar design. I don't know how work my model application ..
On my application all is draw by MFC GDI, I don't use ActiveX or other tools.
So what is the correct way to implement one instance of editor by instance of step ?
For the implementation on this FormView I have :
- Make new dialog in ressource
- Create a derived class of CFormView with the created dialog
- Add one instance in attributes of Step element
- "OnDbClickOnStep" -> Call "Create" with the good position / size, pointer of mainview (in my case the CSrollView derived class)
- Done, FormView inserted in a mainview, I can edit my step events.
? Not done, I lost save button and other function linked to the document with the focus on a control in FormView. The app want a document with this view, how to override this ?
? Error in Proc exchange, for different reason...
You have an idea ?
You normally don't draw anything in the "main frame" (or the "MDI clild frames", in the case of a MDI application), this is done by the library, and imo sufficiently so. You display your data in a CView-derived class.
CView is the base class of all other MFC view classes. It's a simple graphical class - you need to paint it yourself in the OnDraw() member.
CScrollView is a descendant of CView, adding scrolling functionality (scroll-bars are automatically displayed if the scrollable area is bigger than the visible window area).
CFormView is a descendant of CScrollView, displaying a dialog resource-script, containing "controls" (edit-boxes, check-boxes, images, ActiveX etc).
As in your case the "controls" won't be initially known (except maybe for some few special cases) and rather programatically created, the resource script will most likely be empty, so using either CFormView or CScrollView will basically be the same. I would suggest starting with CFormView, and "downgrade" it to CScrollView if CFormView is not necessary or causes you troubles.
What are those "Step" items shown in the pics? ActiveX controls, child dialogs maybe? These work best as child controls on a dialog window. Are they already implemented, or they are just pics of some other software? Btw ActiveX is a way to define controls that can be used in other projects too, without having to include them in the project source.
I'm currently starting to learn how to use C++ Builder. However, I'm stuck on doing something basic, which is to open a window when I click on an element of the menu. I'm ok with the event management, but when I try to display it with the method Show(), it's written when compiling that "the method is not reachable" (I have it in french so I'm not sure about the exact translation). I've tried it different ways, also with the popup element, but I always get this message. Here is the short code that I use to display the window :
TFrame1 * NewPageFormer = new TFrame1(this);
NewPageFormer->Show();
delete NewPageFormer;
NewPageFormer = NULL;
Do you have any idea where the problem comes from?
Thank you
Try with:
TForm1 * NewPageFormer = new TForm1(this);
NewPageFormer->Show();
What you should Show() is a TForm (e.g. take a look at How do I open a new form with a button, using C++ Builder?).
Frames are combinations of components placed on a form-like object, which are considered a cohesive whole.
A frame (TFrame), like a form, is a container for other components. It uses the same ownership mechanism as forms for automatic instantiation and destruction of the components on it, and the same parent-child relationships for synchronization of component properties.
However a frame is more like a customized component than a form, so you cannot directly call the Show() method of a frame.
I would like to update the ribbon from the CDocument derived class because the information relevant for ribbon's status is stored there. The was created by the Wizard and edited in resource manager
Some elements (Buttons, checkboxes) can be updated with ON_UPDATE_COMMAND_UI macro.
But I have a headache with update other things like CMFCRibbonComboBox or CMFCRibbonProgressBar because CCmdUI doesn't provide suitable functions to deal with them (ie AddItem)
Other option using GetDlgItem doesn't work, because neither CDocument nor RibbonBar elements are derived from CWnd.
So what is the way to update CMFCRibbonComboBox and others?
I faced a similar problem with combo boxes on a toolbar. The combo box was used to display the current mouse coordinates of a point in "world coordinate" space while the mouse was moved. I derived my own class for the combo and exposed some methods that would update its contents. I then picked the most appropriate point in the code to make the appropriate calls to those methods. That may be during the paint cycle (eg. OnDraw), or, during idle time. A similar approach of deriving and exposing methods should work for you. The only caveat is to pick the correct location to inject your calls to perform the update.
I first tried RogerRowland's solution, but it soon became annoying to add a function to MainFrame for every trifle , then to call AfxGetMainWnd() from document and apply static_cast on it.
Instead I now store pointers to the ProgressBar and the combobox inside the document. I added the methods to CMainFrame to get them and removed the rest.
The only dificulty with it is the fact that the document is constructed before the main window. So I have to delay the initialisation of the mentioned pointers. I solved it by adding setRibbonBarPointers() to the document and calling it from OnInitialUpdate() of the view
I've used glutdisplayFun(void(*func)) in several of my program to sets the callback display to the current window.And by the use of it, i've rendered different things on the screen. By looking at the documentation of glut, passing null to it is illegal and we can't deregister it also.
The problem is that as we can't deregister it and i write a set of code to display the mainmenu(i.e as shown in the game). And i like to change to next window on the keypress(i.e play the game by clicking on the option play present in the mainmenu).
How to make the glutdisplayfunc call to the mainmenu inactive and and to set the glutdisplayfunc() for calling the next window.
std::%something%<std::function<void(void)>> displayFns;
void myDisplayFunc() {
for (auto& displayFn : displayFns)
displayFn();
}
Now register myDisplayFunc to GLUT and change the displayFns collection.
As for something, map<int, function<...>> would be a good start. Unordered map if you can guarantee your code doesn't need to be called in order. It starts to resemble good old BASIC times with line numbers, but I said upfront it will be a simple answer.
That's not how I would do it, but should do the trick for a quick'n'easy solution.
Funny thing with this is that you can create sets of those to have one element appear in more than one choice rather easily. So maybe it's not that bad after all.
I'm new to wxWidgets and DialogBlocks. I have a form that is created using DialogBlocks and saved as an XRC file. Part of the form has a vertical wxStaticBoxSizer into which are placed two wxScrolledWindow elements. I want to only show one at a time based on what data is to be shown to the user, so I have one marked hidden and left the other one visible. When I try to switch the display and show the widget that was hidden in the XRC and hide the one that was not, the one that I hide goes away fine, but the one that I want to show is not visible. If I resize the window however, it appears. Once it has appeared then I can switch back and forth with no issues. I tried many combinations of showing, enabling, invalidating, getting the sizer and calling RecalcSizes, refresh, layout, and some others. I tried them in different combinations too. Simply calling Show will allow me to toggle between the two, but only after I switch to the one that does not show initially and resize the window. From what I see in the docs. the issue is that wxSizer doesn't allocate space for hidden windows, but there is a flag that can be set to override that behavor. My problem is that DialogBlocks does not expose that feature, so if I manually edit the XRC file the modification will be lost when I, or one of the other developers, save, some changes. Is there a sequence of calls that I can make to tell the sizer to allocate space? The default OnResize handler does something to cause the sizer to allocate space, but I don't know what that is, or how to do it.
This is the flag I found in the docs:
wxRESERVE_SPACE_EVEN_IF_HIDDEN Normally wxSizers don't allocate space
for hidden windows or other items. This flag overrides this behavior
so that sufficient space is allocated for the window even if it isn't
visible. This makes it possible to dynamically show and hide controls
without resizing parent dialog, for example. This function is new
since wxWidgets version 2.8.8
Unfortunately DialogBlocks indeed doesn't allow you to specify this flag. Without it you need to call Layout() after showing a previously hidden control. This will work, provided you call it on the parent with sufficient space to accommodate the children which now need more space (e.g. calling it on the top level parent will always work), but will result in controls visibly shifting which may be not what you want.