Make Fl_String and Fl_Int_Vector private (#789)

- add CMake option 'OPTION_USE_STD'
- add configure option '--enable-use_std'
- move FL/Fl_String.H to src/Fl_String.H
- move FL/Fl_Int_Vector.H to src/Fl_Int_Vector.H
- remove Fl_String from demo program examples/callbacks.cxx
- remove Fl_Int_Vector from public header FL/Fl_Table.H
- some methods of Fl_Table are no longer inline
- add CMake option OPTION_USE_STD to allow std::string in some
  selected functions and methods

Experimental, may be removed before release:

- use either Fl_Int_Vector or std::vector in Fl_Table depending
  on CMake OPTION_USE_STD or configure --enable-use_std

Move all fl_filename* functions that use Fl_String to fluid

Main changes in fluid:
 - add fluid_filename.h and .cxx
 - include "fluid_filename.h" rather than <FL/filename.H>

Update fl_input(), fl_password() and test/ask

- add maxchar parameter to fl_input() and fl_password()
- fl_input_str() and fl_password_str() are optional and return
  std::string if enabled (FLTK_USE_STD)

1 files changed, 18 insertions, 1 deletions

diff --git a/test/ask.cxx b/test/ask.cxx
index 973a42d11..9ff06b45a 100644
--- a/test/ask.cxx
+++ b/test/ask.cxx
@@ -35,7 +35,8 @@
 void rename_button(Fl_Widget *o, void *v) {
   int what = fl_int(v);
   int ret = 0;
-  Fl_String input;
+#if (FLTK_USE_STD)
+  std::string input;
   if (what == 0) {
     fl_message_icon_label("§");
     input = fl_input_str(ret, 0, "Input (no size limit, use ctrl/j for newline):", o->label());
@@ -47,6 +48,22 @@ void rename_button(Fl_Widget *o, void *v) {
     o->copy_label(input.c_str());
     o->redraw();
   }
+#else
+  const char *input;
+  if (what == 0) {
+    fl_message_icon_label("§");
+    input = fl_input("Input (no size limit, use ctrl/j for newline):", o->label());
+    if (!input) ret = 1;
+  } else {
+    fl_message_icon_label("€");
+    input = fl_password(20, "Enter password (max. 20 characters):", o->label());
+    if (!input) ret = 1;
+  }
+  if (ret == 0) {
+    o->copy_label(input);
+    o->redraw();
+  }
+#endif // FLTK_USE_STD
 }
 
 void window_callback(Fl_Widget *win, void *) {