bpo-30870: IDLE: Change sample font when select by key-up/down (#2617)

Patch by Louie Lu.

Lib/idlelib/configdialog.py

@@ -14,7 +14,7 @@
                      StringVar, BooleanVar, IntVar, TRUE, FALSE,
                      TOP, BOTTOM, RIGHT, LEFT, SOLID, GROOVE, NORMAL, DISABLED,
                      NONE, BOTH, X, Y, W, E, EW, NS, NSEW, NW,
-                     HORIZONTAL, VERTICAL, ANCHOR, END)
+                     HORIZONTAL, VERTICAL, ANCHOR, ACTIVE, END)
 from tkinter.ttk import Scrollbar
 import tkinter.colorchooser as tkColorChooser
 import tkinter.font as tkFont
@@ -78,7 +78,7 @@ def __init__(self, parent, title='', _htest=False, _utest=False):
         self.transient(parent)
         self.grab_set()
         self.protocol("WM_DELETE_WINDOW", self.cancel)
-        self.tab_pages.focus_set()
+        self.fontlist.focus_set()
         # XXX Decide whether to keep or delete these key bindings.
         # Key bindings for this dialog.
         # self.bind('<Escape>', self.Cancel) #dismiss dialog, no save
@@ -143,26 +143,24 @@ def create_page_font_tab(self):
         self.space_num = IntVar(parent)
         self.edit_font = tkFont.Font(parent, ('courier', 10, 'normal'))
 
-        ##widget creation
-        #body frame
+        # Create widgets.
+        # body and body section frames.
         frame = self.tab_pages.pages['Fonts/Tabs'].frame
-        #body section frames
         frame_font = LabelFrame(
                 frame, borderwidth=2, relief=GROOVE, text=' Base Editor Font ')
         frame_indent = LabelFrame(
                 frame, borderwidth=2, relief=GROOVE, text=' Indentation Width ')
-        #frame_font
+        # frame_font
         frame_font_name = Frame(frame_font)
         frame_font_param = Frame(frame_font)
         font_name_title = Label(
                 frame_font_name, justify=LEFT, text='Font Face :')
-        self.list_fonts = Listbox(
+        self.fontlist = Listbox(
                 frame_font_name, height=5, takefocus=FALSE, exportselection=FALSE)
-        self.list_fonts.bind(
-                '<ButtonRelease-1>', self.on_list_fonts_button_release)
+        self.fontlist.bind('<<ListboxSelect>>', self.on_fontlist_select)
         scroll_font = Scrollbar(frame_font_name)
-        scroll_font.config(command=self.list_fonts.yview)
-        self.list_fonts.config(yscrollcommand=scroll_font.set)
+        scroll_font.config(command=self.fontlist.yview)
+        self.fontlist.config(yscrollcommand=scroll_font.set)
         font_size_title = Label(frame_font_param, text='Size :')
         self.opt_menu_font_size = DynOptionMenu(
                 frame_font_param, self.font_size, None, command=self.set_font_sample)
@@ -173,7 +171,7 @@ def create_page_font_tab(self):
         self.font_sample = Label(
                 frame_font_sample, justify=LEFT, font=self.edit_font,
                 text='AaBbCcDdEe\nFfGgHhIiJjK\n1234567890\n#:+=(){}[]')
-        #frame_indent
+        # frame_indent
         frame_indent_size = Frame(frame_indent)
         indent_size_title = Label(
                 frame_indent_size, justify=LEFT,
@@ -182,25 +180,26 @@ def create_page_font_tab(self):
                 frame_indent_size, variable=self.space_num,
                 orient='horizontal', tickinterval=2, from_=2, to=16)
 
-        #widget packing
-        #body
+        # Pack widgets.
+        # body
         frame_font.pack(side=LEFT, padx=5, pady=5, expand=TRUE, fill=BOTH)
         frame_indent.pack(side=LEFT, padx=5, pady=5, fill=Y)
-        #frame_font
+        # frame_font
         frame_font_name.pack(side=TOP, padx=5, pady=5, fill=X)
         frame_font_param.pack(side=TOP, padx=5, pady=5, fill=X)
         font_name_title.pack(side=TOP, anchor=W)
-        self.list_fonts.pack(side=LEFT, expand=TRUE, fill=X)
+        self.fontlist.pack(side=LEFT, expand=TRUE, fill=X)
         scroll_font.pack(side=LEFT, fill=Y)
         font_size_title.pack(side=LEFT, anchor=W)
         self.opt_menu_font_size.pack(side=LEFT, anchor=W)
         check_font_bold.pack(side=LEFT, anchor=W, padx=20)
         frame_font_sample.pack(side=TOP, padx=5, pady=5, expand=TRUE, fill=BOTH)
         self.font_sample.pack(expand=TRUE, fill=BOTH)
-        #frame_indent
+        # frame_indent
         frame_indent_size.pack(side=TOP, fill=X)
         indent_size_title.pack(side=TOP, anchor=W, padx=5)
         self.scale_indent_size.pack(side=TOP, padx=5, fill=X)
+
         return frame
 
     def create_page_highlight(self):
@@ -986,13 +985,13 @@ def create_new_theme(self, new_theme_name):
         self.is_builtin_theme.set(0)
         self.set_theme_type()
 
-    def on_list_fonts_button_release(self, event):
-        """Handle event of selecting a font from the list.
+    def on_fontlist_select(self, event):
+        """Handle selecting a font from the list.
 
-        Change the font name to the font selected from the list
-        and update sample text to show that font.
+        Event can result from either mouse click or Up or Down key.
+        Set font_name and example display to selection.
         """
-        font = self.list_fonts.get(ANCHOR)
+        font = self.fontlist.get(ANCHOR if event.type == 3 else ACTIVE)
         self.font_name.set(font.lower())
         self.set_font_sample()
 
@@ -1126,7 +1125,7 @@ def load_font_cfg(self):
         fonts = list(tkFont.families(self))
         fonts.sort()
         for font in fonts:
-            self.list_fonts.insert(END, font)
+            self.fontlist.insert(END, font)
         configured_font = idleConf.GetFont(self, 'main', 'EditorWindow')
         font_name = configured_font[0].lower()
         font_size = configured_font[1]
@@ -1135,9 +1134,10 @@ def load_font_cfg(self):
         lc_fonts = [s.lower() for s in fonts]
         try:
             current_font_index = lc_fonts.index(font_name)
-            self.list_fonts.see(current_font_index)
-            self.list_fonts.select_set(current_font_index)
-            self.list_fonts.select_anchor(current_font_index)
+            self.fontlist.see(current_font_index)
+            self.fontlist.select_set(current_font_index)
+            self.fontlist.select_anchor(current_font_index)
+            self.fontlist.activate(current_font_index)
         except ValueError:
             pass
         # Set font size dropdown.

Misc/NEWS.d/next/IDLE/2017-07-08-17-57-04.bpo-30870.IcR2pf.rst

@@ -0,0 +1,2 @@
+IDLE: In Settings dialog, select font with Up, Down keys as well as mouse.
+Initial patch by Louie Lu.