Preview, PreviewModal y PreviewModeless q diferencía?

[marcoszorrilla]

Esta es la documentación existente en QuickReport:

procedure Preview

Use ‘Preview’ to generate the report and bring up an on screen preview of it. From the preview window the user can choose to print the report.

When calling Preview the report is generated without creating a background thread. If you use a database driver that is thread safe you can use PreviewModal or PreviewModeless to bring up true modal or modeless previews. The window created by Preview is not a true Modal window but the program will not continue until the preview is closed.


procedure PreviewModeless

As ‘ Preview’ except that the program will continue executing on the next line after the PreviewModeless call while the report is being generated and previewed.


procedure PreviewModal

As Preview with the following differences -
When calling PreviewModal the report is generated in a background thread. Some database drivers are not thread safe and this might cause unexpected behavior or program crashes. Only use PreviewModal in situations where it is sure that a thread safe database driver will be used.

No te aconsejo utilizar Preview porque si el usuario te minimiza el informe verás como te ves obligado a cerrar el programa, yo en concreto siempre utilizo PreviewModal.

Un Saludo.