I wanted to make that form would open in a random position on a screen.
I found the similar question here https://stackoverflow.com/a/51314375/19160533
But i didnt get how to implement this.
Im using Delphi 11.
Thanks!
You can set the top and left of the form on FormShow:
procedure TForm1.FormShow(Sender: TObject);
begin
self.Top := Random(1000);
left := Random(2000);
end;
for a better result, you can calculate the desktop dimensions and subtract the form width and height.
Related
I am new to Delphi creating runtime Tgrid and want to add some rows and columns. I googled but not getting any thing. i am at level zero. what i have tried i mentioned it below.This code is showing nothing on my form.
procedure TForm1.Button1Click(Sender: TObject);
var
Grid : TGrid;
begin
Grid := TGrid.Create(Form1);
Grid.Visible := True;
Grid.Margins.Left := 10;
Grid.Margins.Right := 10;
Grid.Margins.Top := 10;
Grid.Margins.Bottom := 10;
Grid.RowCount := 5;
end;
The grid control must have a parent control. Indeed, naturally, the system must know where (on the screen) to put your control!
You probably want the grid to have the form as its parent. If so, just add Grid.Parent := Form1; after the construction of the grid.
Of course, when you add this missing line of code and get to see the grid, you'll very soon notice that your Margins assignments have no effect. That's because by default you control the position of the control (no pun intended) manually using its Top, Left, Height, and Width properties.
But should you start experimenting with the Align property, you'll discover the effect of the margins, if you also set AlignWithMargins to True. For instance, if you set Align to alClient, the control will occupy all of its parent's client area, save the margins.
I have a TDBRadioGroup that I've added to my form.
I'd really like to have the caption to the left of it instead of on top (the form's a little busy and tall, and I'm trying to squeeze it in).
I can add my own label to the left of the Radio Group. But the control insists on reserving space of a Caption that does not exists. Is there a way I can turn it off completely?
The best we've come up with so far is sticking it on a TPanel and then hiding the top couple lines off-panel.
A TGroupBox (and it's descendant TDBGroupBox) are basically wrappers around the Windows GroupBox. The control is designed to sport a user-defined label across the upper-left corner, and doesn't have any style setting to remove it.
So, short of creating your own control to host a series of TRadioButton controls yourself and display them, there's no built-in way to disable the space reserved for the caption. You can suppress the text, of course, by setting the Caption := '', but the padding for the text descenders is not removed simply because the caption isn't displayed.
You can override the paint procedure for TRadioGroup so that the frame is drawn closer to the top of your item list. You could create a new component of type TNoCaptionRadioGroup. You might still have to use the panel trick that you have tried, but by lowering the top of the frame you can grab the space consumed by the non-existent caption. Something like this:
tNoCaptionRadioBox = class(TRadioGroup)
protected
procedure paint; override;
end;
procedure tNoCaptionRadioBox.paint;
var
H: Integer;
R: TRect;
begin
with Canvas do
begin
Font := Self.Font;
H := TextHeight('0');
R := Rect(0, H, Width, Height);
if Ctl3D then
begin
Inc(R.Left);
Inc(R.Top);
Brush.Color := clBtnHighlight;
FrameRect(R);
OffsetRect(R, -1, -1);
Brush.Color := clBtnShadow;
end else
Brush.Color := clWindowFrame;
FrameRect(R);
end;
end;
This is taken from the code for painting a TCustomGroupBox. I have removed the code for drawing the caption and have changed the top of the frame to the full height of the Font. Your actual captioned radio buttons will still be drawn where Windows wants them to be and with the default spacing.
Remember to register the new component by running the package installation tool.
procedure Register;
begin
RegisterComponents('myComponents', [tNoCaptionRadioBox]);
end;
Hi guys after 3 days of not finding the right answer i come to you for help :) , so my question is this i have a TScrollBox component in my form and i create TImage components at FormCreate event this fills up the Scroll-box with components but when i want to scroll through them using Scroll-by it goes way beyond the end of the last component, the code will run on 2 buttons and mouse wheel 1 button left 2 button right and mouse wheel either sides
procedure TForm1.RightButtonClick(Sender: TObject);
var
Coff : Double;
begin
Coff := 6.6;
scrollbarpos := scrollbarpos - 100;
if((scrollbarpos>= -Coff * screen.PixelsPerInch) AND (scrollbarpos<=0)) then
begin
ScrollBox1.ScrollBy(-100,0);
end
else
begin
scrollbarpos := scrollbarpos + 100;
if(scrollbarpos < -(Coff /2) * screen.PixelsPerInch) then
begin
ScrollBox1.ScrollBy(-Round(scrollbarpos+Coff *screen.PixelsPerInch),0);
scrollbarpos := round( -Coff * screen.PixelsPerInch);
end;
end;
end;
this code works but when i change my "Control Panel\Appearance and Personalization\Display" settings from smaller - 100% to medium or large it goes beyond the last component, it has something to do with the Coff value. Any ideas of a more effective way to scroll without using scroll bars because they are invisible.
Project can be found here: http://www.failai.lt/i9famvv1my9f/proj.rar.htm
I'd like to display a form off of a systray icon event, which just shows some information next to the taskbar and disappears itself after some time. The main issue I'm running into is positioning the form in a way that it is both in the correct position and visible. I found a couple of ways to determine where the icon is, but in testing I found them inconsistent based on OS (I attempted this in another app and ended up giving up and using a centered modal form). For example:
procedure GetWorkAreaRect(var outrect: TRect);
// returns the dimensions of the work area.
begin
Systemparametersinfo(SPI_GETWORKAREA, 0, #outrect, 0);
end;
The problem when that works is determining from there where to put the form (above, below, left, right). Any suggestions?
Edit: The problem is in positioning the form in relationship to the system tray icon, not necessarily determining where the system tray icon is. I made another attempt and got it working as long as some conditions are met. Most notably, it doesn't work if the taskbar is set to auto-hide, because the assumption is made that the click is made outside of the work area. This is not true when the form is set to auto-hide.
function PositionForm(X, Y, Width, Height: Integer): TPoint;
// receives mouse-click position in X and Y, form width and height in width and height
// returns Left and Top in TPoint.X and TPoint.Y.
var
workrect: TRect;
resrect: TPoint;
begin
GetWorkAreaRect(workrect);
if Y > WorkRect.Bottom then // taskbar is on bottom
begin
resRect.X := WorkRect.Right - Width;
resrect.Y := WorkRect.Bottom - Height;
end
else
if X > WorkRect.Right then // taskbar is on right
begin
resrect.X := WorkRect.Right - Width;
resrect.Y := WorkRect.Bottom - Height;
end
else
if X < WorkRect.Left then // taskbar is on left
begin
resrect.X := WorkRect.Left;
resrect.Y := WorkRect.Bottom - Height;
end
else
if Y < WorkRect.Top then // taskbar is on top
begin
resrect.X := WorkRect.Right - Width;
resrect.Y := WorkRect.Top;
end;
Result := ResRect;
end;
So on the surface, it seems the issue is to find an independent way to determine where the taskbar resides...or could the logic be extended above to take care of this?
When your notification icon receives the message corresponding to an action, you can query at that point to find out an associated point on the screen.
For example if you are handling WM_RBUTTONUP, WM_CONTEXTMENU etc. in your icon's message procedure you can call GetMessagePos to find out the position on the icon associated with the message.
I wrap this up with the following function so that I can decode the message into a TPoint:
function MessagePoint: TPoint;
begin
Result := TSmallPoint(GetMessagePos());
end;
So what you can do is, in your icon's message procedure, make a note of this point. When you need to show the form, use this point to determine where your icon lives. Since the point can be in the taskbar, you'll need to clip it into the work area.
After your question update it seems you want to know how to find out the location of the taskbar. Do that by calling SHAppBarMessage passing ABM_GETTASKBARPOS.
Windows does not expose a native way to query where system tray icons are positioned, or even if they are visible at all. But you can do it manually with some lower level API trickery, as demonstrated in the following article:
CTrayIconPosition - where is my tray icon?
That works up to XP, at least, maybe even Vista. Windows 7 drastically redesigned the way the system tray acts, so I do not know if these techniques still work anymore.
You can use TJvDesktopAlert to display simple notifications, if you have JCL and JVCL.
procedure TForm1.ShowDesktopAlert(const AHeader, AMessage: string);
begin
with TJvDesktopAlert.Create(nil) do
begin
StyleOptions.DisplayDuration := 5000;
HeaderText := AHeader;
MessageText := AMessage;
AutoFree := True;
Execute;
end;
end;
In a TImage's OnClick event, I would like to extract the x,y coordinates of the mouse. I would prefer them in relation to the image, but in relation to the form or window is just as good.
Mouse.CursorPos contains the TPoint, which in turn contains the X and Y position. This value is in global coordinates, so you can translate to your form by using the ScreenToClient routine which will translate screen coordinates to window coordinates.
According to the Delphi help file, Windows.GetCursorPos can fail, Mouse.CursorPos wraps this to raise an EOsException if it fails.
var
pt : tPoint;
begin
pt := Mouse.CursorPos;
// now have SCREEN position
Label1.Caption := 'X = '+IntToStr(pt.x)+', Y = '+IntToStr(pt.y);
pt := ScreenToClient(pt);
// now have FORM position
Label2.Caption := 'X = '+IntToStr(pt.x)+', Y = '+IntToStr(pt.y);
end;
The Mouse.CursorPos property will tell you the current position of the mouse. If the computer is running sluggishly, or if your program is slow to respond to messages, then it might not be the same as the position the mouse had when the OnClick event first occurred. To get the position of the mouse at the time the mouse button was clicked, use GetMessagePos. It reports screen coordinates; translate to client coordinates with TImage.ScreenToClient.
The alternative is to handle the OnMouseDown and OnMouseUp events yourself; their parameters include the coordinates. Remember that both events need to occur in order for a click to occur. You may also want to detect drag operations, since you probably wouldn't want to consider a drag to count as a click.
As others have said, you can use Mouse.CursorPos or the GetCursorPos function, but you can also just handle the OnMouseDown or OnMouseUp event instead of OnClick. This way you get your X and Y values as parameters to your event handler, without having to make any extra function calls.
How about this?
procedure TForm1.Button1Click(Sender: TObject);
var
MausPos: TPoint;
begin
GetCursorPos(MausPos);
label1.Caption := IntToStr(MausPos.x);
label2.Caption := IntToStr(MausPos.y);
end;
procedure TForm1.Button2Click(Sender: TObject);
begin
SetCursorPos(600, 600);
end;
Found this online somewhere once and saved it in my codesnippet DB :)
This page will probably solve all your questions however... There appear to be functions to go from client to screen coordinates and back etc..
Good luck!
To Firemonkey (FMX):
var
p: TPointF;
begin
p := Screen.MousePos;
end;