ENH: macosx allow figures can be opened in tabs or windows

Allow users to select how new figures are created when opening
new windows. The default is to keep using the system preferences,
but one can also select "tab" or "window" to override the default
system preferences.

Author: greglucas

doc/users/next_whats_new/macosx_windows_tabs.rst

@@ -0,0 +1,7 @@
+macosx: New figures can be opened in either windows or tabs
+-----------------------------------------------------------
+
+There is a new :rc:`macosx.window_mode`` rcParam to control how
+new figures are opened with the macosx backend. The default is
+**system** which uses the system settings, or one can specify either
+**tab** or **window** to explicitly choose the mode used to open new figures.

lib/matplotlib/backends/backend_macosx.py

@@ -145,6 +145,7 @@ def __init__(self, canvas, num):
         icon_path = str(cbook._get_data_path('images/matplotlib.pdf'))
         _macosx.FigureManager.set_icon(icon_path)
         FigureManagerBase.__init__(self, canvas, num)
+        self._set_window_mode(mpl.rcParams.get("macosx.window_mode", "system"))
         if self.toolbar is not None:
             self.toolbar.update()
         if mpl.is_interactive():

lib/matplotlib/mpl-data/matplotlibrc

@@ -701,6 +701,10 @@
                                 # background by default
 #savefig.orientation: portrait  # orientation of saved figure, for PostScript output only
 
+### macosx backend params
+#macosx.window_mode : system   # How to open new figures (system, tab, window)
+                               # system uses the MacOS system preferences
+
 ### tk backend params
 #tk.window_focus:   False  # Maintain shell focus for TkAgg
 

lib/matplotlib/rcsetup.py

@@ -1214,6 +1214,7 @@ def _convert_validator_spec(key, conv):
     "figure.autolayout":       validate_bool,
     "figure.max_open_warning": validate_int,
     "figure.raise_window":     validate_bool,
+    "macosx.window_mode":      ["system", "tab", "window"],
 
     "figure.subplot.left":   validate_float,
     "figure.subplot.right":  validate_float,

src/_macosx.m

@@ -689,6 +689,25 @@ int mpl_check_modifier(
     return 0;
 }
 
+static PyObject*
+FigureManager__set_window_mode(FigureManager* self, PyObject* args)
+{
+    const char* window_mode;
+    if (!PyArg_ParseTuple(args, "s", &window_mode) || !self->window) {
+        return NULL;
+    }
+
+    NSString* window_mode_str = [NSString stringWithUTF8String: window_mode];
+    if ([window_mode_str isEqualToString: @"tab"]) {
+        [self->window setTabbingMode: NSWindowTabbingModePreferred];
+    } else if ([window_mode_str isEqualToString: @"window"]) {
+        [self->window setTabbingMode: NSWindowTabbingModeDisallowed];
+    } else { // system settings
+        [self->window setTabbingMode: NSWindowTabbingModeAutomatic];
+    }
+    Py_RETURN_NONE;
+}
+
 static PyObject*
 FigureManager_repr(FigureManager* self)
 {
@@ -832,6 +851,10 @@ int mpl_check_modifier(
         {"destroy",
          (PyCFunction)FigureManager_destroy,
          METH_NOARGS},
+        {"_set_window_mode",
+         (PyCFunction)FigureManager__set_window_mode,
+         METH_VARARGS,
+         "Set the window open mode (auto, tab, window)"},
         {"set_icon",
          (PyCFunction)FigureManager_set_icon,
          METH_STATIC | METH_VARARGS,