I am writing a screensaver in Delphi. I want is to display a TpresentationFrm on each monitor, fullscreen. To this end, I have written the following (incomplete) program:
program ScrTemplate;
uses
...
{$R *.res}
type
TScreenSaverMode = (ssmConfig, ssmDisplay, ssmPreview, ssmPassword);
function GetScreenSaverMode: TScreenSaverMode;
begin
// Some non-interesting code
end;
var
i: integer;
presentationForms: array of TpresentationFrm;
begin
Application.Initialize;
Application.MainFormOnTaskbar := True;
case GetScreenSaverMode of
ssmConfig:
Application.CreateForm(TconfigFrm, configFrm);
ssmDisplay:
begin
SetLength(presentationForms, Screen.MonitorCount);
for i := 0 to high(presentationForms) do
begin
Application.CreateForm(TpresentationFrm, presentationForms[i]);
presentationForms[i].BoundsRect := Screen.Monitors[i].BoundsRect;
presentationForms[i].Visible := true;
end;
end
else
ShowMessage(GetEnumName(TypeInfo(TScreenSaverMode), integer(GetScreenSaverMode)));
end;
Application.Run;
end.
When the ssmDisplay
code is executed, two forms are indeed created (yes, I have exactly two monitors). But they both appear on the first monitor (index 0, but not the primary one).
When stepping through the code, I see that the Screen.Monitors[i].BoundsRect
are correct, but for some reason the forms obtain incorrect bounds:
Watch Name Value (TRect: Left, Top, Right, Bottom, ...)
Screen.Monitors[0].BoundsRect (-1680, 0, 0, 1050, (-1680, 0), (0, 1050))
Screen.Monitors[1].BoundsRect (0, 0, 1920, 1080, (0, 0), (1920, 1080))
presentationForms[0].BoundsRect (-1680, 0, 0, 1050, (-1680, 0), (0, 1050))
presentationForms[1].BoundsRect (-1920, -30, 0, 1050, (-1920, -30), (0, 1050))
The first form get the desired position, but the second does not. Instead of going from x=0 to 1920, it occupies x=-1920 to 0, i.e. it appears on the first monitor, above the first form. What is wrong? What is the proper procedure to accomplish what I want?
The form has to be visible in order to set the bounds using BoundRect.
Reverse the lines like this:
presentationForms[i].Visible := true;
presentationForms[i].BoundsRect := Screen.Monitors[i].BoundsRect;