As we all know, EVT_CHAR is a basic event which don't propagate to wxTopLevelWindow(wxFrame and wxDialog).
But I have a wxDialog without any wxWidgets controls on it, and need to handle user keyboard input (handle EVT_CHAR event).
I saw the wiki about catch key events globally, but it's not work on EVT_CHAR event as EVT_CHAR event need to be translated to get user input
And I have try to have wxDialog a hided children wxWindow which foward EVT_CHAR to its parent wxDialog. It works on Windows platform, and not on OSX which is my target platform.
Is there a way to implement it ?
Why do you need to handle all keyboard entry in the dialog itself? There are two typical cases for this that I know of: either you want to handle the key presses in several different controls in the same way, or you need to handle some particular key press (e.g. WXK_F1) in all controls. The former can be done by binding the same event handler to several controls. The latter -- by using accelerator table with an entry for the key that you want to handle specially.
Finally, I implemented what I want according to this:
http://trac.wxwidgets.org/ticket/15345
In wxWidgets 3.0, wxNSView implementes NSTextInputClient protocol, which makes every widgets can handle EVT_CHAR correctly.
But EVT_CHAR still cannnot be handle by wxDialog or wxFrame, because of some call of IsUserPanel() function. So I commented some call of IsUserPanel to make it work for me.
Related
I try to fill the qlineedits of an external application. It has Qt5WindowIcon class, and I was able to find that it receives messages using WinAPI, it uses PeekMessage, PostMessage and DefWindowProc, but the trick is that it doesn't have any child controls this can be seen in Spy++ and also I tried manually with EnumChildWindos and it always returns false.
Are the Qt controls somewhat different and independent from WinAPI? I heard there are so called alien widgets, are they painted manually in user mode? I also tried setting breakpoints on GetWindowText, SetWindowText, GetDlgItemText, SendMessage+WM_GETTEXT , and I never got any bp hits, seems like Qt doesn't use this API to set/get text from QLineEdit.
Is there any way that I can find control id? Or the only option would be code injection with QLineEdit methods hooking?
I am currently developing a user interface DLL that uses the WIN32 API. The DLL must work for numerous platforms, XP, WIN CE, etc. I have managed to incorporate docking, anchoring and so on but appear to have a problem regarding owner-drawn buttons. I can draw the button's correct state, focus, clicked, default. However, I cannot receive key notifications. I specifically want to perform a click operation on a button that currently has focus, should the user press enter.
Note that I am using a windows message loop rather than a dialog message loop. I use windows hooks to hook into the window creation and set the user data to 'point' to my control instance. If I test for WM_KEYDOWN in the main message loop I can get a handle to my button control instance and could forward the message to the relevant control. Unfortunately, I am dealing with a lot of legacy code and this may not be an ideal solution.
So, my question is what is the best way forward. Is subclassing the button control's window procedure a viable option or is there an easier way?
Many thanks in advance.
The comments above are correct. The button with focus should be getting the key messages. But buttons don't (by themselves) respond to Enter--they respond to Space. It sounds like what you're missing is the typical dialog keyboard navigation, like Tab key moving the focus and Enter activating the "default" button.
If you've got a typical Windows message pump, and you want the keyboard behavior normally associated with dialogs, then you need to use the IsDialogMessage API in your message loop. This means your window is essentially a "modeless dialog".
Looks like standard window proc subclassing should do the trick. See http://msdn.microsoft.com/en-us/library/windows/desktop/ms633591(v=vs.85).aspx for details.
I am developing a Tetris game using C++ in combination with the plain old WinAPI, GDI and GDI+. The applications window contains a few UI controls along with a static control that is used for painting the game state. I am using a keyboard hook so that I can respond to the arrow keys to move the current block and the space bar to drop the block.
However, the keystrokes also affect the UI. Moving the arrow keys may change the radio or combobox selection state and pressing the space bar may trigger a button or checkbox, depending on which control currently has focus.
Is there a way to prevent this from happening? My temporary hack is to force focus on a hidden textbox. I would appreciate a cleaner solution.
If you're using a WH_KEYBOARD_LL or a WH_KEYBOARD keyboard hook, you can return 1 from the hookproc to prevent the key from being passed to the rest of the system.
Do no call the next hookproc in that case.
However, this could play havoc with things that use hooks and come after you in the hook chain.
If you're writing a GDI app, you have a message loop already, is there any reason you're not using the message loop to look for KEY_UP/KEY_DOWN messages?
You can set other controls so they will not take focus...
Is this a real hook (set with SetWindowsHook)? If so, you could return a non zero value from the hookproc when you handle the message, and Windows will not pass the message along to the dialog.
In .Net there is a feature called KeyPreview. How can I do this in WinApi. Maybe I don't necessarily need this but my hWnd has WM_KEYDOWN, but it does not receive it when my Text Box has focus. How can I achieve this?
Thanks
*Using pure Win32API...
is there an alternative, how could I handle the Text Box's WM_KEYDOWN?
You can try subclassing the edit control. Either "instance subclassing", to trap messages for only one window, or "global subclassing" to trap messages for all windows of that class (in your application, not system-wide).
The example here (http://msdn.microsoft.com/en-us/library/ms997565.aspx) shows how to subclass an edit control and trap the WM_GETDLGCODE message -it wouldn't be that difficult to change it to WM_KEYDOWN.
You may have problems previewing the keys used for dialog commands, e.g. TAB or RETURN, as they may be trapped higher up the food chain. You may need to look at changing WM_GETDLGCODE as well.
If you use MFC you can look at PreTranslateMessage (I am not sure regarding to PreTranslateMessage, but you can easily to verify whether to enough to override the function).
You can set keyboard hook.
There is no such a possibility in WinAPI to catch the messages belonging to controls in window procedure of parent window (although some exceptions exist).
What .NET basically does is that it routes all messages of all controls including their parent window to a single window procedure. Then it's easy to catch all the messages in one place.
This is your way to go - to set window procedures of all the controls into single procedure and there to catch all the messages
As window procedure also receives hwnd parameter, it's then also easy to determine the control to which the message belongs.
I'm creating a plugin framework, where my application loads a series of plugin DLL's, then creates a new window and pass this new window's handle to the plugin. The plugin can, then, use this handle to create their own GUI.
Everything seems to be working very well. The only problem is that when I press TAB on a plugin widget (An editbox, for example), it doen't jump to another widget. I figured out that some Windows messages are passed, and some others aren't. The WM_KEYDOWN is passed for other keys, because I can type on the editbox, but this message doesn't handle TAB key.
Hope somebody has a hint.
I'm using Borland VCL with CBuilder, but I think I could use any framework under WIN32 to create these plugins, since they never know how their parent windows were created.
It's very complex matter indeed.
When you hit TAB focus jumps to another control only when these controls belong to a Modal Dialog Box. In fact there are some buttons like ESC, LEFT, RIGHT, DOWN, UP, TAB which modal dialog message function treats in a special way. If you want these keys to behave in similar way with modeless dialog box or any other window you should change you message processing function and use IsDialogMessage inside. You'll find more information about IsDialogMessage function in MSDN also to better understand this stuff you may check as well Dialog Boxes section.
And, as was mentioned before, you should set WS_TABSTOP and WS_GROUP styles when needed.
Good luck!
I believe you'll have to take the following steps:
Subclass your edit controls (and other controls as needed).
Capture the WM_KEYDOWN message in your edit control's WndProc.
Check to see if the shift key is currently held down (using GetKeyState or similar).
Call GetWindow, passing in a handle to your edit control and either GW_HWNDPREV or GW_HWNDNEXT depending on whether shift is held down. This will give you the handle to the window that should receive focus.
Call SetFocus and pass in the window handle you got in step 4.
Make sure you handle the case where your edit controls are multiline, as you might want to have a real tab character appear instead of moving to the next control.
Hope that helps!
I believe you suffer from having a different instance of the VCL in each of your dlls and exes. Classes from the dll are not the same as the ones from your exe, even if they are called the same. Also global variables (Application, Screen) are not shared between them. Neither is the memory since they both have their own memory manager.
The solution is to have the dlls and the exe share the VCL library and the memory manager. I am not a BCB developer, but a Delphi developer. In Delphi we would just use the rtl and the vcl as runtime packages. Maybe you could do the BCB equivalent.
A DLL has its own TApplication object.
to provide uniform key handling. when the DLL Loads.
assign the DLL::TApplication to the EXE::TApplication
Be sure to do the reverse on exit.
--
Michael