Buttons

FLTK provides many types of buttons:

• Fl_Button - A standard push button

• Fl_Check_Button - A button with a check box

• Fl_Light_Button - A push button with a light

• Fl_Repeat_Button - A push button that repeats when held

• Fl_Return_Button - A push button that is activated by the Enter key

• Fl_Round_Button - A button with a check circle

For all of these buttons you just need to include the corresponding <FL/Fl_xyz_Button.H> header file. The constructor takes the bounding box of the button and optionally a label string:

Fl_Button *button = new Fl_Button(x, y, width, height, "label");
Fl_Light_Button *lbutton = new Fl_Light_Button(x, y, width, height);
Fl_Round_Button *rbutton = new Fl_Round_Button(x, y, width, height, "label");
      

Each button has an associated type() which allows it to behave as a push button, toggle button, or radio button:

button->type(0);
lbutton->type(FL_TOGGLE_BUTTON);
rbutton->type(FL_RADIO_BUTTON);
      

For toggle and radio buttons, the value() method returns the current button state (0 = off, 1 = on). The set() and clear() methods can be used on toggle buttons to turn a toggle button on or off, respectively. Radio buttons can be turned on with the setonly() method; this will also turn off other radio buttons in the same group.