We are working with Firemonkey since version 1, and still find difficulties updating components that are currently visible on the screen. There are many 'ways' to request a repaint in Firemonkey, perhaps too many:
Applying a style (ApplyStyle event) - mostly when it becomes visible on screen
Requesting ".repaint" - some components have this
Requesting ".realign" - sometime works, current versions of FMX seem to drop / hide it
Requesting ".invalidate" - some components, mostly forms, have this
Requesting ".invalidateRect" - most components have this
Calling the ApplyStyle event manually - not guaranteed to work and design-wise is incorrect...
Given the lacking documentation for the platform, is there a "well defined" way to change the visual appearance (internal values of a style) when a component is already displayed? I.e. a listboxItem that is already present and visible on screen, a TGrid cell, and so on. Would appreciate your thoughts...
I don't think there's a single unified 'correct way' to refresh the visual of components in Firemonkey.
However, as a recommendation from personal experience, I'd take the .repaint route - this method is at the TControl level, and so it precedes primitives and styled controls (which are generally made up of primitives) and so applies to all visual controls. It also doesn't require parameters, so it's a good all-round solution.
I have noted that Firemonkey has always had an issue correctly repainting controls of it's own accord. Often I'm left with a 'shadow' of the previous visual of a control/primitive, and must call .repaint manually to update it. This got noticeably worse with FM2 and FM3 (presumably due to optimizations made for mobile platforms), and so doing a manual .repaint -- especially where effects such as TGlow and moving or rotating controls/primitives are concerned, has become a standard practice for me.
I am trying to modernize the look of our older Delphi 7 application now that we are using Delphi XE-2. I experimented with the TRibbon, and although I like it, it probably is not the correct solution since we currently use a TMainMenu and make many runtime changes to it - our users can modify the main menu. But the default Mainmenu looks old, especially compared to the image shown.
What I am trying to do is something very close to the attached image, especially with the background color, but I don't quite understand how this was done. Can anyone tell me if this example (the File/View/Insert section) uses a TMainMenu, or is it Buttons on a Toolbar ? If we require a customizable main menu, do you think the example shown is an option ?
This example image comes from DevExpress Print Sample library.
Edit : I am new here so I can't include the image. Here is the link :
http://www.devexpress.com/Products/VCL/ExPrintingSystem/gallery.xml
The second image, the green one that says "Print Preview".
You could use the TActionMainMenuBar but the simpler solution for you is to Use Vcl styles, pick a theme, modify the graphical properties of a MainMenu component and then use StyleHooks to force the style just for the MainMenu component without using it for the whole application.
I have imported ActiveX controls before and were able to use them same as regular VCL controls. Every now and again I bump into a control that imports fine but doesn't show up at run-time and only show a little block in the designer.
The latest one is an ActiveX wrapper for the Scintilla editor and it shows me a grey block 100 pixels wide and 41 pixels high with the control icon on it. At run-time there's nothing, so it baiscally acts like a non-visual component even though it's supposed to be an edit control.
My questions are:
Has anyone else seen this?
Is this a known issue with Delphi's ActiveX support, or is it more likely an issue with the control itself?
I have never seen this behavior, I suspect it's a problem with the control.
i know that windowless controls are not magic. A windowless control can have input focus (e.g. Internet Explorer). Input focus is nothing more than drawing either:
a blinking cursor
a dotted line around the perimeter
a slight blue tinge on a button
and when the user begins mashing keys, reacting appropriately. You know the keystrokes are meant for that focused control, because that's the control has focus.
In the case of my (Windows®) window, i would have to know that my windowless child control (let's pretend it's a descendant of TGraphicControl) gets the keyboard events. So during my form's OnKeyDown, OnChar, OnKeyUp, i would need to pretend they are going to my windowless child control.
Which i can do, but it is a pain.
But then the user will probably want to use Tab navigation, and i'll have to somehow intercept Delphi's normal tab control order handling, and hook in myself to say that this thing is the next (and previous) in the tab order.
Which i can do, but it is a pain.
And then there's ActiveControl, which doesn't understand anything except TWinControl's. So if Delphi ever tries to figure out who has focus, it will go insane. So i'd have to have an alternate implementation of ActiveControl.
Which i can do, but it is a pain.
In other words: is this just too much work? i'm fighting eveything that Delphi is, all so i can have a few dozen windowless controls accessible through keyboard input? The Delphi designers never contemplated using interactive windowless controls, and if i try now to work it in, i'll just stuck in the hurtlocker?
Delphi gave me the chance of aiding me willingly, but i have elected the way of pain.
Some further explanation of windowless controls is needed.
Not every control you interact with has to be a windows control. It is quite possible to have focus on, and send keyboard input to, a control that is not a Windows window.
For example, nearly every control you see in an Internet Explorer browser window is a windowless control. In the following screenshot you can see an edit control, which you can type in, and a button which (in this screenshot) has focus:
You can see the dotted focus rectangle, and the button is bluish (which on Windows indicates that it has focus).
If i were to press Spacebar while the Google Search button has focus, it would press the button. The reason this works is because Microsoft wrote an entire widget library of controls. These controls look and feel (almost) exactly like the regular common controls - they are very nearly exact clones of the Windows common controls, right down to the themes being applied.
Mozilla Firefox and Google Chrome also use a widget library of controls. They don't use Microsoft's built-in windowed controls, but instead use a library of graphical, interactive, windowless widgets.
And if you have a suitable development environment, then the windowless widgets work just like "normal" windowed controls. GTK+ is a widget library, and Glade is an IDE that lets you layout controls in that widget library.
i don't know in what development environment Firefox, Chrome, or Blender were created in, but their widgets support windowless controls.
So now onto my question.
Unless i'm mistaken, it appears to me that although Delphi supports a base TControl, (which has width, height, and can paint itself), it cannot receive keyboard focus. It seems to me that Borland never designed Delphi's VCL as a generic widget library. The only evidence i have to support this is that a Form's ActiveControl is a TWinControl:
property ActiveControl: TWinControl;
That doesn't mean that Delphi could be, or must be, limited to windowed controls. The VCL widget library could be extended to support giving focus to windowless controls.
But perhaps Delphi already supports windowless controls, and i just don't realize it? Is there already an established mechanism in Delphi to support giving focus to TControl's? But i'm a reasonably smart guy, and i'm pretty sure Delphi's VCL cannot do what other widget libraries can do.
Which then leads to another question: how much work would be be to subclass forms and such to support it? Is there someone else out there, perhaps someone on TeamB, who's much smarter than i, who has already tried it, and come to the conclusion that it's impossible?
i'm asking now, up front, if trying to add windowless control support is damn near impossible (i.e. futile) - so that i don't spend weeks on it for nothing. i'm trying to draw on the knowledge of a community of Delphi developers.
i'm asking a question.
It's futile to build windowless controls and fit them into Delphi's VCL framework.
You bring up Internet Explorer as an example. But in that case, it's entirely in charge of everything that resides on it. It has its own internal notion of what the active control is, but think about what it looks like from the outside: It's just one giant control. When you ask the OS what has focus, the single browser control has it, no matter which of the browser's subcontrols appears to have focus.
When you press Tab, it looks to the OS as though the browser has simply consumed a tab character, just like edit controls do. Edit controls move the cursor over a few spaces and add tab characters to their internal buffers; browser controls move the cursor to another region of the display.
You're thinking of doing all this on a Delphi TForm. Delphi forms already have a framework for managing the active control and handling keystrokes, and you're going to have to fight it all. If you want windowless controls, go the Internet Explorer route and build your own container control to hold them so that you can remain in charge of everything that happens inside it.
Your container can be a VCL control, but the things you put on it probably can't — they'll still be expecting to use the VCL focus- and keyboard-handling rules. Notice how you can't put ordinary Windows controls in Internet Explorer, either. Anything you put there needs to go through specific ActiveX interfaces. Maybe you'll need interfaces, too, or maybe you can just make your own set of control classes that descend from some special ancestor class you design to work with your container. Don't start with TGraphicControl; it's too entrenched in the VCL to be usable as the basis for your offshoot control library.
It will be a lot of work, but then again, so was Internet Explorer.
Yes, it is futile.
And it's not Delphi's fault, you're just fighting Windows itself.
If you need a control that behaves like a windowed control, use a windowed one.
And you're right, trying to recreate the whole API stack of windowed controls from scratch is a pain.
Yup, you pretty much have it figured out. Using windowless controls means that you lose everything Windows can do to help you. Having more than a couple on a single actual window is pain.
Most of these programs were most likely not originally developed using RAD type tools so had no choice but to re-invent the wheel. One of the largest advantages of Delphi is the deep VCL and 3rd party component support to provide the look you desire.
One technique that I have used with great success to reduce the amount of window handles used in a complex (tax preparation) form based application was to draw the text on a canvas, and moved a single TCustomEdit decendant to the position the user was editing. It was trivial to capture the TAB/Up/Down keys and move the edit to the appropriate position. The challenge we discovered was in drawing a hot rectangle around the mouse hovered field. We ended up with a grid array of TObject, where the array element would be nil (no field), a TLIst (grid contains multiple fields) or a a class that contained our field descriptor. This reduced the amount of range checks we had to perform since it was more likely that the box only contained a single field, or at most 4 fields.
fpGUI Toolkit is an example of what you want. The latest fpGUI code in the source code repository is based on a multi-windowed design. That simple means every widget/component has a window handle, but Windows or Linux does nothing with that window, other that basic notification messages (mouseenter, mouseexit, etc). fpGUI still has full control over where each component goes, if they are focusable, how they look etc. Some widgets/components in fpGUI are non-windowed components too. eg: TfpgScrollbar, TfpgMainMenu, the button in a ComboBox etc.
If you want a true non-windowed version, mean there is only one top-level window that has a window handle, all other widgets/components inside that window doesn't actually exist to the OS (they have no window handles), then fpGUI can help too. The initial design of fpGUI Toolkit was based on such a design. Again, look in the source code repository for the v0.4 branch of code. I that design, fpGUI had to handle absolutely everything, creating mouseenter/mouseleave events, translate co-ordinate systems for container components, handle (fake) component focus states etc... Yes the initial design is a LOT of work, but then you have a very portable framework which can easily be applied to other OSes too.
And yes, fpGUI is fully implemented in the Object Pascal language using the Free Pascal compiler to give me cross-platform support. Currently fpGUI runs on Windows, Linux (32 & 64-bit), Windows Mobile and Embedded Linux (ARM) devices.
I have no idea of what your problem really is, here, but I think this little history may be relevant...
We have an application which fills out a dozen forms. The user may fill out additional forms, and also change values filled out by the application it self.
Now, in our first implementation, we used windowed components for every single input field, so that the fields could receive focus and input. That turned out to be a big problem, because all this windows took a lot of resources.
We now have windowless controls for every input field. That means that all we end up with, is a combined drawing of the form and its input fields. When the user clicks inside the drawing, or uses some keystrokes to move/set focus, we create a new windowed control for the clicked field. When the user moves to the next input field, we destroy the first window, and create a new one. This way we only have one windowed control which again gave us a nice speed improvement.
Again - I have no idea of what you really want to manage. TWinControl is a TWinControl for a reason, but there may be a solution to what you want, what ever that would be...
I think fgGUI may help you out.
Do check its Wiki first.
I think you can use this framework for your application in Delphi as it is written totally in Pascal. Actually it is based on FreePascal ;)
HTH
In Delphi 2010 (don't know about other versions) Application.HintColor seems to have no effect when running on Windows 7. On XP it gives the desired color. Any workarounds for this?
HintColor is like some of the other *Color properties in the VCL in that if you are running a themed application on a themed OS, they may be ignored when painting the control. Hints are a little different, because for them it's Vista or above, not XP or above. You can see this if you look at THintWindow.Paint in Controls.pas - it specifically paints the Vista gradient background if it's Vista and if themes are enabled.
This is normally a good thing, because you want your application to fit the look-and-feel of the OS and the user's preferences.
If you really want to override this, you will need to:
Subclass THintWindow
Get your application to use this new hint class when showing hints
In this class, override the painting methods to draw as you wish
Create a new hint class descending from THintWindow somewhere (more on what to implement below.) To get the application to use your new class for hints, assign an event handler to TApplication.OnShowHint (the easiest way to do this is via a TApplicationEvents component on your main form) and change the HintInfo parameter's HintWindowClass field to be your new class.
In your new hint class, you will need to override Paint and NCPaint. NCPaint will paint the border, and you will want to paint a non-themed border (probably using DrawEdge.) Change Paint to fill in the background with your colour of choice, and then draw text using DrawText in the hint's rectangle with appropriate text wrapping and alignment flags. If you look at the VCL code closely you can see a couple of rectangle offsets hardcoded, and you probably want to mimic these to get the same rectangles in your code as the VCL uses.
You can make all sorts of interesting variations of hints using this technique. One I made recently changed the painting so it drew a bold caption and then had other information under that, for example.
Finally: why are you setting the colour? Is it to warn the user of something or provide some other feedback? If so, consider using more than the colour - you can change anything you want about a hint using this technique. Try painting a warning icon or using rich-formatted text instead. I'd recommend you try to keep to the general theme look, and code tweaks to the themed painting, not overriding it entirely, because unless there's a very good reason you should try to keep to the OS / look the user has chosen.
No, not directly. If you have the runtime themes enabled it will take the system color for the hint. (IOW, the hint will be 'themed'). It is like setting a color for a button with the themes enabled (given that you can do this).
However you can use other 'hint' engines. For example you can use TjvBallonHint and/or TjvDesktopAlert (perhaps in conjunction with TjvDesktopAlertStack) from JEDI's JVCL which is free. There are also other (free & paid) alternatives. Also, if you want you can implement your own hint window.
HTH
Turning the 'enable runtime themes' off makes it work.
In Delphi 2010, you have TCustomHint class. You can derive a new class from it which draws a new type of hint.
You can assign your new class to CustomHint property of your forms or any other controls, and Delphi will use your custom hint class for showing hint for that control.
You can check source code of TBalloonHint class which is a sample TCustomHint descendant in Controls.pas