As in the subject, how to create and display a message in reaction?

Is there something like MessageBox("Title Box, please choose yes or no", yesno);

Hello,

trying to understand how Amiga programming works.

I have this source to open a window containing a string gadget:

Object *open_text_window_new(struct Screen *scr, struct Menu *menu)
{

Object *winobj;

Hello,
in my Workbench application I need to display a bitmap theme (texture: metal, wood, ...) as a filling background for the GUI.
According to SDK 53.20 documentation, the filler image class (filler_ic.doc) seems to be there for the purpose, am I wrong? Any tips how to use it?

Thanks, regards

Using a Reaction class String gadget in a Reaction class window, I'd like the
program to be able to tell when the gadget goes active.

Does anyone know how to get that activation information?

Reaction HandleInput doesn't have a "WMHIGadgetDown" and WMHIActive tells
you that the Window is active, but not which gadget.

The WINDOW_IDCMPHook hook never seems to get called with an
IDCMPGadgetDown, no matter what is in WINDOW_IDCMPHookBits.

Hi,

I am writing a reaction prefs program and want to have a file gadget that shows a button and a string box next to it which contains the current path/file that has been selected.
I create this using the following:

LAYOUT_AddChild, OBJ(OBJ_DISKRSTRING)=GetFileObject,
GA_RelVerify, TRUE,
STRINGA_MinVisible, 36,
GA_ID,OBJ_DISKRSTRING,
End,