revalidate() vs. repaint()?

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Rene Ruppert - 28 Apr 2005 09:21 GMT

Hi,

do I interpret the docs correctly that validate(), invalidate() and
revalidate() are only useful if I use a layout manager?
I know: "ALWAYS use a layout manager" :-), but if I don't a repaint() should
be enough, or am I wrong?

Regards,

René

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A. Bolmarcich - 28 Apr 2005 15:06 GMT

> Hi,
>
> do I interpret the docs correctly that validate(), invalidate() and
> revalidate() are only useful if I use a layout manager?
> I know: "ALWAYS use a layout manager" :-), but if I don't a repaint() should
> be enough, or am I wrong?

The validate(), invalidate(), and revalidate() methods are useful if an
extension of Container overrides its doLayout() method, say to do
something other than the default behavior of invoking the
layoutContainer(Container) method of the LayoutManager of the Container.

Using a custom Container that overrides its doLayout() method to
layout the Container is an alternative to using a custom LayoutManager.

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Rene Ruppert - 28 Apr 2005 15:27 GMT

Hi,

> The validate(), invalidate(), and revalidate() methods are useful if an
> extension of Container overrides its doLayout() method, say to do
[quoted text clipped - 3 lines]
> Using a custom Container that overrides its doLayout() method to
> layout the Container is an alternative to using a custom LayoutManager.

So this means, if I use setLayout(null), re/in/validate() is of no use,
correct?

René

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A. Bolmarcich - 28 Apr 2005 19:05 GMT

> Hi,
>
[quoted text clipped - 8 lines]
> So this means, if I use setLayout(null), re/in/validate() is of no use,
> correct?

Whether it is of use depends on whether the doLayout() method has been
overridden to do something even when the LayoutManager is null.

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revalidate() vs. repaint()?

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