Check out whether or not Focus Rect is required (Delphi) - delphi

Imagine that we have a form with two buttons on it. I run the application and I click on the first button. nothing happens and no focus rectangle is displayed. But when I press a key, it shows a focus rect on the button and even if I click on the second one, it moves the focus rect to it. So it doesn't display the focus rect unless I press a key. I'm creating my own component and I need to know whether or not I should display the focus rect to draw it.
How do I know it?

I think it's not meant to display the focus rectangle by default, that's until a keyboard accelerator is used. Read UI State on MSDN, that suggests WM_QUERYUISTATE should be used to determine if keyboard accelerators or focus indicators should be drawn or not.

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VoiceOver : is 'accessibilityActivationPoint' really useful?

I tried and understood what could be the purpose of the accessibilityActivationPoint but in vain.
When a focused accessible element is activated, that property should indicate VoiceOver the specific area it's going to activate when a user double-taps the element (Apple reference) : for me, it's always the selected element itself.
I understood the selected element is considered as a block by VoiceOver, whatever the other elements inside. Once a double tap occurs to activate this block, VoiceOver calls accessibilityActivate to know what to perform (Apple reference).
1/. I've written many tests by creating a custom view including a switch control. Whatever the value of accessibilityActivationPoint inside (or outside on another switch control), the value of the switch control never changes. Is it a proper use case or am I totally wrong ?
2/. When we gather many elements inside one accessible element, how is VoiceOver able to activate one of them while they aren't accessible by definition ? Pointing one of them thanks to the accessibilityActivationPoint should work ?
Personally, I couldn't make it work and think that I'm really confusing accessibilityActivationPoint and accessibilityActivate.
Any help would be appreciated, thanks in advance.
Yes, you have the right idea with accessibilityActivate and accessibilityActivationPoint. Note that, in order for it to work, the accessibilityActivationPoint needs to be a point within the Control that you are trying to activate in on-screen coordinates (use the convert function!).
I think the short answer is "yes" to answer your second question, but, just to clear up confusion about when Accessibility Activation Point is useful, I'll go into more detail about it.
By default (aka, the default behavior for AcessibilityActivate()), when any view is activated by VoiceOver, VoiceOver will send a "tap gesture" to the center of the view. The position of this "tap gesture" can be changed by updating the accessibilityActivationPoint attribute on a view. Below, I have an example for how this property can be used.
Let's say you have a blank button (in the image below, the button is the gray box) next to some text:
For the purpose of accessibility, you may want to make the entire view that holds the button and text an Accessibility Element (so that VoiceOver users can easily understand that the button is associated with the text "Worldspace Attest"). In the image below, I am using Accessibility Inspector to show that the view holding both of these elements is an Accessibility Element.
Notice in these images that the button is not in the center of the view, but rather, it is to the right. When you activate this view using VoiceOver, the view will not select the button; instead, it will send a "tap" to the center of the view (which is the same as tapping the text, which does not do anything). In order to select the button, you have to set the view's accessibilityActivationPoint to be the on-screen coordinates of the button:
view.accessibilityActivationPoint = self.convert(button.center, to: UIApplication.shared.windows.first)
This should make it so that this button is usable by a VoiceOver user.
I hope this information clears up any confusion about the Accessibility Activation Point property. The example I used above can be found in this repository in the "Active Control Name" demo.

How do I prevent menu and toolbar clicks stealing focus from a floating form?

I want to achieve the same effect as in Visual Studio 2010+, where if you float an editor on top of the main form, clicking on a main form menu or toolbar button doesn't cause the main form to steal focus; instead the floating window retains focus.
Without this it becomes impossible to invoke any main menu command that operates on a focused control when the focused control is in a floating window - because the control you wanted to operate on loses focus just as the command is invoked.
(Ironically, if you look closely at this image you'll see that the selection in the editor is muted, indicating that the editor control doesn't have focus. Visual Studio seems to be doing something slightly devious to achieve the illusion that the floating window is still focused.)
The solution is very easy if you are using TActionMainMenuBar and TActionToolBar.
First the menu bar: TActionMainMenuBar has a property AutoFocus, which is True by default. Set this to False and then clicking on the menu won't automatically give focus to the form containing the menu. Instead, the form that previously had focus will retain it.
Now the tool bar: TActionToolBar doesn't have an AutoFocus property. Instead you need to handle its OnMouseActivate event and return maNoActivate.
Note that returning maNoActivate from an OnMouseActivate handler doesn't work for all controls. Some controls such as TButton will give themselves the focus when clicked regardless of the return result from the OnMouseActivate handler. But in the case of TActionToolBar we do get the effect we are after.
It took me a while to find this though, and even searching Google for a page containing both 'AutoFocus' and 'OnMouseActivate' elicits no useful results (other than, presumably, this page once it gets indexed). So I hope this answer will help someone else.

Keyboard pushes the whole view up in WP7

I have 3 grids:- Header,Body and Footer with Body having textboxes.
I have included the Body inside a scrollviewer so that user can type as much data as he wants in the texboxes of Body.
But when the Keyboard pops up the whole view is pushed at top and I cannot see the Header.
The textboxes have wrapping on and also accepts return.
Can the scrollview move up the text when keyboard pops up?
Thanks and Regards,
Kanaya
Not entirely sure if this will help. How about some XAML?
You could capturing the Focus event of the text box that brings the Keyboard up. In that event you could set the scrollViewer.HorizontalOffset property to some caluclated value to get whatever you want in view.
Edit: HorizontalOffest is only a getter user ScrollToHorizontalOffset instead
You probably can make it scroll up like you want, but it will appear very strange to seasoned users of the WP7 operating system. Expected behavior for text input is exactly what you described, the notion Microsoft (I believe) is trying to hit here is that when you want to type something in, you want to clear everything else out of view, and only focus on the textbox at hand.

Virtual TreeView update hint within cell on mouse move

I'm using a TVirtualStringTree as a grid which is working pretty well.
I'm using the treeviews hint functionality to show a hint when the user positions the mouse over a cell. I've had to change HintMode to hmHint as I want my hints to appear regardless of the cell text length.
What I'm trying to do now is to display a different hint depending on whereabouts the mouse is within the cell.
I can do this no problem before the hint is displayed by using the OnGetHint event. My problem is this event is only raised a next time when the user moves the mouse to another cell.
I can't see to find a way to update the hint while its displayed and the mouse is moved within the same cell
I've looked at suggestions for other controls, using the Application's OnShowHint event but they just seem to make the hint disappear and not show again.
Anyone got any ideas?
Thanks
Update
After some investigation here is what I have found in case it helps someone come up with a solution:
The CMHintShow method sets the CursoRect field of the HintInfo record to the bounds of the cell. This seems to stop the VCl from triggering the hint code again until the mouse moves out of this rect (TApplication.HintMouseMessage).
If i set the CursorRect to something smaller than the cell bounds the hint will update. I use VTs in a few places for different purposes, so I can't make these changes directly. Would be good to get a solution that doesn't require this change.
In TBaseVirtualTree.CMHintShow right near the top, the code reads:
if PtInRect(FLastHintRect, HintInfo.CursorPos) then
Exit;
If you comment this out then the behaviour is closer to what you are looking for. The hint window won't show again if you move the mouse within the same cell, but if you click then it will.
I can't seem to find any way to make the hint window show in the same cell without that mouse click though!

TStringGrid dirty hack - Restricting the selection to one single row

I have a heavily modified control based on TStringGrid. I want to allow the user to make selections in this grid but restrict the selection one single row (the current row).
Implementation:
When the user presses the left mouse button I am using a dirty hack: On OnMouseDown event I capture the mouse cursor and keep it on the current row. The user can move the mouse device up and down on its pad but the cursor will not go up or down. It will stay on the current row. When the user releases the button (OnMouseUp event), I release the capture.
However, this hack is as I said very dirty. There are several problems. For example, if the user presses the left mouse button (LMB) and then without releasing that button it presses the right button, the associated pop-up menu will pop but the mouse capture will never be released. So, the mouse will be locked in a screen region until the user will has the brilliant idea to click the LMB one more time to unlock the mouse. This may be a bug in D7. There is a separate post about it here: TStringGrid - OnMouseUp is not called!
There is a elegant way to do this?
Edit:
OnSelectCell is not working. OnSelectCell event is called only once when you click the cell. If you keep the button pressed and move the mouse to expand the selection, OnSelectCell will not be called again.
Indeed MoveCurrent appears only in TCustomGrid.MouseDown.
Use the OnSelectCell event and set the CanSelect var parameter depending on whether the ARow parameter is what you want.
A nice solution
Check the options property on TStringGrid
There is an Option called 'goRangeSelect'
Set this to false using the object inspector
Or programatically this can be done by
StringGrid1.Options - [goRangeSelect];
This answer is not elegant at all, but it works.
My solution is NOT to use the PopupMenu property of the StringGrid. Instead I implemented my own PopUpMenu property. Works almost perfect. There is on small problem, the bottom of the pop-up menu appears next to the cursor and not its top.

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