examples: Add IUP text box example

Author: dkl

examples/GUI/IUP/textbox.bas

@@ -0,0 +1,70 @@
+#include once "IUP/iup.bi"
+const NULL = 0
+const NEWLINE = !"\n"
+
+function on_click_ok cdecl(byval handler as Ihandle ptr) as long
+	var dialog = IupGetHandle("dialog")
+	var textbox = IupGetHandle("textbox")
+	var label = IupGetHandle("label")
+
+	var text = *IupGetAttribute(textbox, IUP_VALUE)
+
+	print "OK clicked! content of textbox: <" + text + ">"
+
+	IupSetAttribute(label, IUP_TITLE, _
+		"Thanks. You entered <" + text + ">." + NEWLINE + _
+		"val() result: " & val(text) & ". " + NEWLINE + _
+		"IupGetInt() result: " & IupGetInt(textbox, IUP_VALUE) & "." + NEWLINE + _
+		"IupGetFloat() result: " & IupGetFloat(textbox, IUP_VALUE) & "." _
+	)
+
+	'' Recalculate the window layout. Since we changed the label text, it
+	'' may require more space. This may require us to even increase the
+	'' entire dialog's size to make room for the bigger label. According to
+	'' IUP documentation doing this requires setting the SIZE attribute of
+	'' the dialog, then call IupRefresh() on it. I'm not 100% sure whether
+	'' this is the right/best way to do it.
+	IupSetAttribute(dialog, IUP_SIZE, NULL)
+	IupRefresh(dialog)
+
+	function = IUP_DEFAULT
+end function
+
+IupOpen(NULL, NULL)
+
+'' Create a window with a text box, ok button, and a label
+var textbox = IupText(NULL)
+var okbutton = IupButton("OK", "on_click_ok")
+var label = IupLabel("Hello! Enter some text and click OK.")
+var vbox = IupVbox(textbox, okbutton, label, NULL)
+var dialog = IupDialog(vbox)
+
+'' Window title
+IupSetAttribute(dialog, IUP_TITLE, "Text box example")
+
+'' Make text box accept numbers only (instead of arbitrary text)
+'' According to the IUP documentation, the IupText() control accepts a FILTER
+'' attribute on Windows, which can have the values LOWERCASE, UPPERCASE or NUMBER.
+'' Thus FLOAT does not seem to be valid!?
+'IupSetAttribute(textbox, IUP_FILTER, "FLOAT")
+'' However, NUMBER does not disallow letters to be entered on Windows XP either...
+'IupSetAttribute(textbox, IUP_FILTER, "NUMBER")
+
+'' Adjust layout a little bit
+IupSetAttribute(textbox, IUP_EXPAND, "YES")
+IupSetAttribute(okbutton, IUP_EXPAND, "YES")
+IupSetAttribute(label, IUP_EXPAND, "YES")
+IupSetAttribute(vbox, IUP_GAP, "4")
+IupSetAttribute(vbox, IUP_ALIGNMENT, "ACENTER")
+IupSetAttribute(vbox, IUP_MARGIN, "4x4")
+
+'' Set callbacks and handles
+IupSetFunction("on_click_ok", @on_click_ok)
+IupSetHandle("dialog", dialog)
+IupSetHandle("textbox", textbox)
+IupSetHandle("label", label)
+
+'' Show window and run main loop
+IupShow(dialog)
+IupMainLoop()
+IupClose()