ローカルの画像が更新されたら自動で再表示

ImageWatcherApp.py

# -*- coding: utf-8 -*-
import tkinter as tk
from PIL import Image, ImageTk
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler
import pystray
from pystray import MenuItem as item
import threading
import os
import time


class ImageChangeHandler(FileSystemEventHandler):
    def __init__(self, callback, target_path):
        self.callback = callback
        self.target_path = os.path.abspath(target_path)

    def on_modified(self, event):
        if os.path.abspath(event.src_path) == self.target_path:
            time.sleep(0.1)
            self.callback()


class ImageViewer(tk.Tk):
    def __init__(self, image_path):
        super().__init__()
        self.image_path = image_path

        self.overrideredirect(True)
        self.attributes('-topmost', True)
        self.configure(bg='black')
        self.withdraw()

        self.zoom_level = 1.0
        self.is_fit_mode = False
        self.original_img = None
        self.topmost_var = tk.BooleanVar(value=True)

        self.label = tk.Label(self, bg='black')
        self.label.pack(expand=True, fill='both')

        self.context_menu = tk.Menu(self, tearoff=0)
        self.context_menu.add_checkbutton(label='常に最前面', variable=self.topmost_var, command=self.sync_topmost)
        self.context_menu.add_command(label='フィット表示切替 (F)', command=self.toggle_fit)
        self.context_menu.add_separator()
        self.context_menu.add_command(label='非表示にする', command=self.withdraw)
        self.context_menu.add_command(label='終了 (Esc)', command=self.quit_app)

        self.bind('<Escape>', lambda e: self.quit_app())
        self.bind('f', lambda e: self.toggle_fit())
        self.label.bind('<Button-3>', self.show_context_menu)
        self.label.bind('<Button-1>', self.start_move)
        self.label.bind('<B1-Motion>', self.do_move)
        self.bind('<MouseWheel>', self.handle_zoom)

        self.load_image()
        self.start_watching()
        self.setup_tray()
        self.deiconify()

    def load_image(self):
        if not os.path.exists(self.image_path):
            return
        try:
            with Image.open(self.image_path) as img:
                self.original_img = img.copy()
            self.refresh_display()
        except Exception as e:
            print(f'Load Error: {e}')

    def refresh_display(self):
        if self.original_img is None:
            return

        orig_w, orig_h = self.original_img.size
        sw, sh = self.winfo_screenwidth(), self.winfo_screenheight()

        if self.is_fit_mode:
            ratio = min(sw / orig_w, sh / orig_h)
            nw, nh = int(orig_w * ratio), int(orig_h * ratio)
            self.geometry(f'{nw}x{nh}+{(sw-nw)//2}+{(sh-nh)//2}')
        else:
            nw, nh = int(orig_w * self.zoom_level), int(orig_h * self.zoom_level)
            self.geometry(f'{max(nw, 1)}x{max(nh, 1)}')

        resized = self.original_img.resize((max(nw, 1), max(nh, 1)), Image.Resampling.LANCZOS)
        self.photo = ImageTk.PhotoImage(resized)
        self.label.config(image=self.photo)

    def handle_zoom(self, event):
        self.zoom_level *= 1.1 if event.delta > 0 else 0.9
        self.is_fit_mode = False
        self.refresh_display()

    def toggle_fit(self):
        self.is_fit_mode = not self.is_fit_mode
        if not self.is_fit_mode:
            self.zoom_level = 1.0
        self.refresh_display()

    def sync_topmost(self):
        self.attributes('-topmost', self.topmost_var.get())

    def start_move(self, event):
        self._drag_data = {'x': event.x, 'y': event.y}

    def do_move(self, event):
        dx, dy = event.x - self._drag_data['x'], event.y - self._drag_data['y']
        self.geometry(f'+{self.winfo_x() + dx}+{self.winfo_y() + dy}')

    def show_context_menu(self, event):
        self.context_menu.post(event.x_root, event.y_root)

    def setup_tray(self):
        icon_img = self.original_img.resize((64, 64)) if self.original_img else Image.new('RGB', (64, 64), (255, 255, 255))
        menu = pystray.Menu(
            item('Show', self.show_window, default=True),
            item('Hide', self.withdraw),
            item('Exit', self.quit_app)
        )
        self.tray_icon = pystray.Icon('image_watcher', icon_img, 'Image Watcher', menu)
        threading.Thread(target=self.tray_icon.run, daemon=True).start()

    def show_window(self):
        self.after(0, self.deiconify)
        self.after(0, lambda: self.attributes('-topmost', True))

    def start_watching(self):
        event_handler = ImageChangeHandler(lambda: self.after(0, self.load_image), self.image_path)
        self.observer = Observer()
        self.observer.schedule(event_handler, os.path.dirname(os.path.abspath(self.image_path)), recursive=False)
        self.observer.start()

    def quit_app(self):
        self.observer.stop()
        self.tray_icon.stop()
        self.destroy()


if __name__ == '__main__':
    import sys

    path = str()
    if len(sys.argv) > 1:
        path = sys.argv[1]
    if os.path.exists(path):
        app = ImageViewer(path)
        app.mainloop()
    else:
        print(f'File not found: {path}')