How to verify if the checkbox is checked in a Delphi TTaskDialog?
OK, this should be easy, but I do not find the solution, at least not in the not so good documentation.. In a TTaskDialog
, you have the option to add one check-box. You can control its initial state by means of the tf开发者_运维知识库VerificationFlagChecked
flag in Flags
. But how to get the state after the dialog has been Execute
d?
Of course one can use the OnVerificationClicked
event and toggle a local variable, initially equal to the initial state of the checkbox, on each call. But one would expect a more natural solution.
O my God, Embarcadero has made a mistake.
A few tests of mine showed that if the check-box initially is unchecked, but is checked by the user, then the tfVerificationFlagChecked
flag will be set. But if the flag is initally set, and the user unchecks the box, then tfVerificationFlagChecked
will not be removed from the Flags
set. And this is not strange. The VCL code does
Result := TaskDialogIndirect(LTaskDialog, {$IFNDEF CLR}@{$ENDIF}LModalResult,
{$IFNDEF CLR}@{$ENDIF}LRadioButton, {$IFNDEF CLR}@{$ENDIF}LVerificationChecked) = S_OK;
FModalResult := LModalResult;
if Result then
begin
FButton := TTaskDialogButtonItem(FButtons.FindButton(FModalResult));
FRadioButton := TTaskDialogRadioButtonItem(FRadioButtons.FindButton(LRadioButton));
if LVerificationChecked then
Include(FFlags, tfVerificationFlagChecked);
end;
Notice that the flag is included if the checkbox is checked when the dialog closes, but there is no code to remove the flag if the box is unchecked by the user.
Of course, one would expect the latter part of the code to have read
if LVerificationChecked then
Include(FFlags, tfVerificationFlagChecked)
else
Exclude(FFlags, tfVerificationFlagChecked)
I think I'll go with the OnVerificationClicked
manual toggling approach.
Can't you read Flags
after the dialog is closed to see whether tfVerificationFlagChecked
is still present?
In Delphi XE7 (possibly earlier versions, too) this seems to have been resolved.
choice := tfVerificationFlagChecked in tskbox.Flags;
choice, a boolean variable, can return the checked status.
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