In my application there are a lots of dialogs being opened and closed all the time. The dialogs are non-modal.
In order to save some performace, we are "recycling" some of the more complicated controls. When one dialog is closed, the controls are not destroyed, but their pointers are stored in an array so that they can be reused when another dialog is opened.
The problem is that after the control is positioned in the new dialog, it does not receive all the messages. For instance the message WM_DRAWITEM (the control is derived from CListCtrl) is not being sent anymore. The WM_LBUTTONDOWN on the other hand is still arriving. It is as if the control does not know its class anymore. The NC area (border and list header) is being painted correctly.
Did anyone have similar problems? What could be wrong? Can the controls be "detached" and "reattached" in this way at all?
For CListCtrl to respond to WM_DRAWITEM image it is needed it has the LVS_OWNERDRAWFIXED style. Are you sure you have it set?
And from http://msdn.microsoft.com/en-us/library/windows/desktop/bb774739(v=vs.85).aspx , it seems it only occurs if it is in Report view (Seems strange to me!).
Related
In the simple Dialog below:
// choice of layout has no impact:
Container cont=new Container(new TextModeLayout(3, 1));
//Container cont=new Container(new BoxLayout(BoxLayout.Y_AXIS));
TextComponent firstName=new TextComponent().label("First Name").text(person.firstname);
TextComponent lastName=new TextComponent().label("Last Name").text(person.lastname);
TextComponent cost=new TextComponent().label("Cost per Session").text(person.getCostString());
cost.getField().setConstraint(TextArea.DECIMAL);
// NOTE HERE
// doesn't work: // works:
cont.add(firstName); // cont.add(firstName.getField());
cont.add(lastName); // cont.add(lastName.getField());
cont.add(cost); // cont.add(cost.getField());
Dialog.show("Edit Client", cont, new Command(CANCEL), new Command(OK));
Nothing appears in the Dialog unless I add the TextField instead of the TextComponent to my container at the NOTE HERE comment. This means I lose the nice appearance of the labelled input fields (yes I know I could label them myself, but they wouldn't look as good on different devices). My choice of layout manager at the top does not affect this issue (I've tried several). I can't find evidence online to conclude there's an incompatibility here, adding TextComponents and other InputComponents works fine on a Form, just not in a Dialog.
I'm having the same problem in another Dialog that uses PickerComponents. The PickerComponent doesn't appear unless I add the Picker itself, and then the Picker spawned from a Dialog looks all wrong. I'm hoping the simpler code question above will answer this quandary as well.
It's worth noting I've made no theme changes and this problem is noted in both the Android and Apple skins as well as on an actual Android phone. Thanks in advance for any help!
You shouldn't do input in a Dialog as it creates a very problematic user experience. If you would like things to look like they are in a dialog you can use styles and layouts to make a Form feel like a Dialog but you shouldn't use a Dialog.
The reason this fails is a bit complicated but here are the high level problems with using a dialog:
Dialogs don't grow implicitly - This is a huge problem for text input as the component needs space to resize with input and even more so for the animated TextComponent which needs to shift things around. The size of a Dialog is determined when it's shown and that's a big problem
This becomes a bigger problem on Android where the screen resizes during input and distorts the dialog completely. It's one of those things you'll only see on the device because it's really hard to simulate the virtual keyboard.
Scrollability is hard in a Dialog and text components need a scrollable parent so you can scroll between the various edit components
Picker component uses a form of Dialog to show input and this can collide with your dialog
Dialogs are hard to get right for suspend/resume behavior. Suspend/resume happens when the app is minimized or sent to the background. E.g. say you have an incoming call while typing in the dialog. When you go back to the app we want to show the last form. If we show the dialog it will block and we won't know which parent form to show anyway. So when an app is suspended dialogs are just disposed in the default code generated in the main class. It makes more sense.
I followed this link http://www.wintellect.com/devcenter/jprosise/handling-the-back-button-in-windows-10-uwp-apps and "successfully" make my button work. I mean I can make my backbutton work between pages. However, if I navigate to a control which is inside this page and will cover the whole screen, then it would not allow me to back to the page. I will stuck in that control.
I'm wondering how to solve this problem. Currently I can think two possible ways (0) Override OnBackRequested() inside the control's code behind or viewmodel? (1) Override OnHardwareButtonsBackPressed() inside the control's code behind or viewmodel?. I don't know if these are correct way to do it or there is some better way to do it. Another reason for me to override is that I need to make some changes to the page navigation behavior.
As you have guessed, you simply need to hide the control again when the back button is pressed or back is requested in some other way. I would listen for the BackRequested event (not the HardwareButtons.BackPressed event) in the page's code-behind, and in the handling method you can check to see if the control is currently shown. The reason I recommend the BackRequested event is because it is universal, while HardwareButtons.BackPressed only works on a phone. Anyway, if the control is visible, then hide it, and set the Handled property of the event arguments to true. If the control is already hidden, don't do anything special to handle the event (because in that case you will want the navigation system to handle it by navigating to the previous page, if there is one). There are many aspects to navigation in Windows 10 -- please see these pages on Navigation and the SystemNavigationManager.
I'm working in a legacy application using MFC.
We have a mechanism to enable/disable controls depending on some business logic.
This mechanism is implemented in the CView-derived class. The way it works is all the views in the application derived from a common CView-derived class (CBaseView) and on the PreTranslateMessage all controls of the view are enabled/disabled.
This worked fine so far because all controls send at least WM_PAINT message when they need to be painted. So the system worked without the user having to move the mouse or anything. I recently added some drawing features and I had to use WS_EX_COMPOSITE to get ride of some flickering. With this flag activated my CView-derived class is not getting any called to PreTranslateMessage when creating the view....so the controls are not disabled until the user moves the mouse over the control.
I understand there is no way to send WM_PAINT using WS_EX_COMPOSITE but is there other message I can use to get the same behaviour???
Edited:
I am currently using the OnIdle approach but it has a big drawback, the windows doesn't become idle until after drawing all the controls...so when you enter the screen al controls are enabled and inmediately they are disabled...this makes a quite ugly effect!
More solutions???
Thanks in advance...
The logical place to enable/disable controls would be CView::OnUpdate, it is called by the framework after the view's document has been modified and from OnInitialUpdate(); you can also call this function if there is some change that would trigger re-evaluation of your business logic.
EDIT
After reading the question a bit more closely, what you could also do is to post a private message at the end of OnInitialUpdate and "catch" it in your PreTranslateMessage:
PostMessage(WM_APP, 0, 0);
Calling InvalidateRect followed by UpdateWindow against the window in question will mark the entire client area as dirty and force an immediate repaint. Remember that WM_PAINT is not really a message, in the queue in the usual sense, it is pushed out after all other messages have been processed for that window, which would include any invalidations of the area being drawn. No message is generated at all if there are no invalid segments of the active window display.
I have a bunch of control objects (TextBoxes, to be precise) that get injected into my code using the #FXML annotation during the FXML load.
I would like to save the states of these controls, specifically the text values, when the user closes the Scene by clicking the close box on the title bar.
However, when I trap the CloseRequest event in an OnCloseRequest handler I find that the values of the control variables are null (the original injection works, so this is something that happens in between the loading of the FXML and the calling of OnCloseRequest).
Can anyone explain this behavior and/or suggest how I can get the functionality that I want?
TIA
onCloseRequest is
Called when there is an external request to close this Window. ...
(from Javadoc). One of the meanings of "external request" is when you close the window through OS native window close button. The closeRequest event is not triggered through the programmatic stage.close() or stage.hide() calls. So consider to handle onHiding or onHidden events.
Otherwise post your OnCloseRequest handler code.
How can I obtain the Window Rect of a CDialog which is based on a dialog template. The dialog is not and can not be visible
It might be tricky with CDialog, because if you dont show the CDialog, the window handle is not created and you cant call GetClientRect.
Might i suggest calling CreateDialogIndirect instead to create the dialog, then you can get the client rect. You dont need to show the dialog. I think as long as the window handle is created, the GetClientRect should work. I am not an expert though and its been many years since i have written MFC code.
Well...
In Windows API-land, you could load the resource yourself (FindResourceEx, LoadResource), understand the binary structure of the dialog template resource (some clues at http://blogs.msdn.com/oldnewthing/archive/2004/06/22/162360.aspx), convert the size of the dialog in the dialog template from dialog units to pixels (check out http://msdn.microsoft.com/en-us/library/ms645475(VS.85).aspx).
I'd be curious why you'd want to do this, though.