TWPPreview content not displayed properly after changing Parent property

Steven

Hi,

The content of a TWPPreview gets lost if the parent changes.

Example:

Code

if (WPPV_Preview.Parent = Panel2) then begin    WPPV_Preview.Parent := (Panel1);    WPPV_Preview.LoadFromString('Test123');  end else WPPV_Preview.Parent := (Panel2);

The example switches the TWPPreview between two panels.

Furthermore, sometimes I get an access violations when loading content from stream.
The access violation occurs at

Code

function TWPCustomRtfEdit.LoadFromStream(s: TStream; FormatName: string = ''; WithClear: Boolean = FALSE): Boolean;
// ...
Result := Memo.LoadFromStream(s, not IsEmpty, FormatName);

I use the latest WPTools version from 07.10.2015 with Delphi XE8.

This is an urgent issue as I am right closed to a new release.

Thanks in advance :)

/Steven

support

A TWPPreview was created to create a second view on a TWPRichText which already holds text. This is why it has the property WPRichText.

Then this code works:

if WPPreview1.Parent=Panel1 then
WPPreview1.Parent := Panel2
else WPPreview1.Parent := Panel1;

I recommend to use a TWPRichText and make it readonly.

Steven

Hi,

Thanks for the fast reply.

Unfortunately, the code you posted doesn't work. It's the same behavior. The document disapears after the parent changed.

So, it looks like a bug.

support

Hi,

I agree, the problem happens and also there are other problems, too,
IF the TWPPreview is abused to hold the text. It is not designed to do so. It must be connected to a TWPRichText which holds the text. If you do not have one, don't use the TWPPreview. Use a TWPRichText instead.