Real-World Applications ======================= This section provides complete, real-world examples that demonstrate how to build professional applications using ThreePaneWindows. Text Editor Application ----------------------- A complete text editor with file management: .. code-block:: python import tkinter as tk from tkinter import ttk, filedialog, messagebox import os from threepanewindows import EnhancedDockableThreePaneWindow, PaneConfig class TextEditorApp: """A complete text editor application.""" def __init__(self): self.root = tk.Tk() self.root.title("Professional Text Editor") self.root.geometry("1200x800") self.current_file = None self.file_modified = False self.setup_ui() def setup_ui(self): """Set up the user interface.""" # Create menu self.create_menu() # Configure panes file_config = PaneConfig( title="File Explorer", icon="📁", default_width=250, min_width=200, detachable=True ) editor_config = PaneConfig( title="Editor", icon="📝", detachable=False ) outline_config = PaneConfig( title="Document Outline", icon="📋", default_width=200, min_width=150, detachable=True ) # Create enhanced window self.window = EnhancedDockableThreePaneWindow( self.root, left_config=file_config, center_config=editor_config, right_config=outline_config, left_builder=self.build_file_explorer, center_builder=self.build_editor, right_builder=self.build_outline, theme_name="blue" ) self.window.pack(fill=tk.BOTH, expand=True) # Status bar self.status_bar = tk.Label(self.root, text="Ready", relief=tk.SUNKEN, anchor=tk.W) self.status_bar.pack(side=tk.BOTTOM, fill=tk.X) def create_menu(self): """Create the application menu.""" menubar = tk.Menu(self.root) # File menu file_menu = tk.Menu(menubar, tearoff=0) file_menu.add_command(label="New", accelerator="Ctrl+N", command=self.new_file) file_menu.add_command(label="Open", accelerator="Ctrl+O", command=self.open_file) file_menu.add_command(label="Save", accelerator="Ctrl+S", command=self.save_file) file_menu.add_command(label="Save As", accelerator="Ctrl+Shift+S", command=self.save_as_file) file_menu.add_separator() file_menu.add_command(label="Exit", command=self.exit_app) menubar.add_cascade(label="File", menu=file_menu) # Edit menu edit_menu = tk.Menu(menubar, tearoff=0) edit_menu.add_command(label="Undo", accelerator="Ctrl+Z", command=self.undo) edit_menu.add_command(label="Redo", accelerator="Ctrl+Y", command=self.redo) edit_menu.add_separator() edit_menu.add_command(label="Cut", accelerator="Ctrl+X", command=self.cut) edit_menu.add_command(label="Copy", accelerator="Ctrl+C", command=self.copy) edit_menu.add_command(label="Paste", accelerator="Ctrl+V", command=self.paste) menubar.add_cascade(label="Edit", menu=edit_menu) # View menu view_menu = tk.Menu(menubar, tearoff=0) view_menu.add_command(label="Word Wrap", command=self.toggle_word_wrap) view_menu.add_command(label="Line Numbers", command=self.toggle_line_numbers) menubar.add_cascade(label="View", menu=view_menu) self.root.config(menu=menubar) # Keyboard bindings self.root.bind('', lambda e: self.new_file()) self.root.bind('', lambda e: self.open_file()) self.root.bind('', lambda e: self.save_file()) def build_file_explorer(self, frame): """Build the file explorer panel.""" # Toolbar toolbar = tk.Frame(frame, bg="#f0f0f0", height=30) toolbar.pack(fill=tk.X) toolbar.pack_propagate(False) tk.Button(toolbar, text="📁", command=self.browse_folder).pack(side=tk.LEFT, padx=5, pady=2) tk.Button(toolbar, text="🔄", command=self.refresh_files).pack(side=tk.LEFT, padx=2, pady=2) # File tree self.file_tree = ttk.Treeview(frame) file_scroll = ttk.Scrollbar(frame, orient=tk.VERTICAL, command=self.file_tree.yview) self.file_tree.configure(yscrollcommand=file_scroll.set) self.file_tree.pack(side=tk.LEFT, fill=tk.BOTH, expand=True, padx=5, pady=5) file_scroll.pack(side=tk.RIGHT, fill=tk.Y, pady=5) # Bind double-click to open file self.file_tree.bind('', self.on_file_double_click) # Load initial directory self.load_directory(os.getcwd()) def build_editor(self, frame): """Build the main editor panel.""" # Editor toolbar editor_toolbar = tk.Frame(frame, bg="#e0e0e0", height=35) editor_toolbar.pack(fill=tk.X) editor_toolbar.pack_propagate(False) # File info self.file_label = tk.Label(editor_toolbar, text="Untitled", font=("Arial", 10, "bold"), bg="#e0e0e0") self.file_label.pack(side=tk.LEFT, padx=10, pady=5) # Editor frame editor_frame = tk.Frame(frame) editor_frame.pack(fill=tk.BOTH, expand=True) # Line numbers (optional) self.line_frame = tk.Frame(editor_frame, bg="#f8f8f8", width=40) self.line_numbers = tk.Text(self.line_frame, width=4, bg="#f8f8f8", fg="#666", font=("Consolas", 11), state=tk.DISABLED, wrap=tk.NONE) # Main text editor self.text_editor = tk.Text(editor_frame, wrap=tk.WORD, font=("Consolas", 12), undo=True, maxundo=50) # Scrollbars v_scroll = tk.Scrollbar(editor_frame, orient=tk.VERTICAL, command=self.text_editor.yview) h_scroll = tk.Scrollbar(editor_frame, orient=tk.HORIZONTAL, command=self.text_editor.xview) self.text_editor.configure(yscrollcommand=v_scroll.set, xscrollcommand=h_scroll.set) # Pack editor components self.text_editor.grid(row=0, column=1, sticky="nsew") v_scroll.grid(row=0, column=2, sticky="ns") h_scroll.grid(row=1, column=1, sticky="ew") editor_frame.grid_rowconfigure(0, weight=1) editor_frame.grid_columnconfigure(1, weight=1) # Bind text changes self.text_editor.bind('', self.on_text_change) self.text_editor.bind('', self.update_cursor_position) self.text_editor.bind('', self.update_cursor_position) def build_outline(self, frame): """Build the document outline panel.""" tk.Label(frame, text="Document Outline", font=("Arial", 11, "bold")).pack(pady=5) # Outline tree self.outline_tree = ttk.Treeview(frame) outline_scroll = ttk.Scrollbar(frame, orient=tk.VERTICAL, command=self.outline_tree.yview) self.outline_tree.configure(yscrollcommand=outline_scroll.set) self.outline_tree.pack(side=tk.LEFT, fill=tk.BOTH, expand=True, padx=5, pady=5) outline_scroll.pack(side=tk.RIGHT, fill=tk.Y, pady=5) # Document stats stats_frame = tk.LabelFrame(frame, text="Statistics", font=("Arial", 10, "bold")) stats_frame.pack(fill=tk.X, padx=5, pady=5) self.stats_labels = {} stats = ["Lines", "Words", "Characters"] for stat in stats: stat_frame = tk.Frame(stats_frame) stat_frame.pack(fill=tk.X, padx=5, pady=2) tk.Label(stat_frame, text=f"{stat}:", font=("Arial", 9)).pack(side=tk.LEFT) self.stats_labels[stat] = tk.Label(stat_frame, text="0", font=("Arial", 9, "bold")) self.stats_labels[stat].pack(side=tk.RIGHT) self.update_stats() # File operations def new_file(self): """Create a new file.""" if self.check_save_changes(): self.text_editor.delete(1.0, tk.END) self.current_file = None self.file_modified = False self.file_label.config(text="Untitled") self.update_title() def open_file(self): """Open a file.""" if self.check_save_changes(): filename = filedialog.askopenfilename( title="Open File", filetypes=[("Text files", "*.txt"), ("Python files", "*.py"), ("All files", "*.*")] ) if filename: try: with open(filename, 'r', encoding='utf-8') as file: content = file.read() self.text_editor.delete(1.0, tk.END) self.text_editor.insert(1.0, content) self.current_file = filename self.file_modified = False self.file_label.config(text=os.path.basename(filename)) self.update_title() self.update_outline() except Exception as e: messagebox.showerror("Error", f"Could not open file: {str(e)}") def save_file(self): """Save the current file.""" if self.current_file: try: content = self.text_editor.get(1.0, tk.END + '-1c') with open(self.current_file, 'w', encoding='utf-8') as file: file.write(content) self.file_modified = False self.update_title() self.status_bar.config(text=f"Saved: {self.current_file}") except Exception as e: messagebox.showerror("Error", f"Could not save file: {str(e)}") else: self.save_as_file() def save_as_file(self): """Save the file with a new name.""" filename = filedialog.asksaveasfilename( title="Save As", defaultextension=".txt", filetypes=[("Text files", "*.txt"), ("Python files", "*.py"), ("All files", "*.*")] ) if filename: self.current_file = filename self.save_file() self.file_label.config(text=os.path.basename(filename)) # Edit operations def undo(self): try: self.text_editor.edit_undo() except tk.TclError: pass def redo(self): try: self.text_editor.edit_redo() except tk.TclError: pass def cut(self): try: self.text_editor.event_generate("<>") except tk.TclError: pass def copy(self): try: self.text_editor.event_generate("<>") except tk.TclError: pass def paste(self): try: self.text_editor.event_generate("<>") except tk.TclError: pass # Utility methods def check_save_changes(self): """Check if changes need to be saved.""" if self.file_modified: result = messagebox.askyesnocancel("Save Changes", "Do you want to save changes to the current document?") if result is True: self.save_file() return True elif result is False: return True else: return False return True def on_text_change(self, event=None): """Handle text changes.""" self.file_modified = True self.update_title() self.root.after_idle(self.update_stats) self.root.after_idle(self.update_outline) def update_title(self): """Update the window title.""" title = "Professional Text Editor" if self.current_file: title += f" - {os.path.basename(self.current_file)}" else: title += " - Untitled" if self.file_modified: title += " *" self.root.title(title) def update_stats(self): """Update document statistics.""" content = self.text_editor.get(1.0, tk.END + '-1c') lines = content.count('\n') + 1 if content else 0 words = len(content.split()) if content else 0 chars = len(content) self.stats_labels["Lines"].config(text=str(lines)) self.stats_labels["Words"].config(text=str(words)) self.stats_labels["Characters"].config(text=str(chars)) def update_outline(self): """Update document outline.""" # Clear existing outline for item in self.outline_tree.get_children(): self.outline_tree.delete(item) # Parse content for headings (simple example) content = self.text_editor.get(1.0, tk.END) lines = content.split('\n') for i, line in enumerate(lines, 1): line = line.strip() if line.startswith('#'): level = len(line) - len(line.lstrip('#')) heading = line.lstrip('# ').strip() if heading: self.outline_tree.insert("", "end", text=f"Line {i}: {heading}") def update_cursor_position(self, event=None): """Update cursor position in status bar.""" cursor_pos = self.text_editor.index(tk.INSERT) line, col = cursor_pos.split('.') self.status_bar.config(text=f"Line {line}, Column {int(col)+1}") # File explorer methods def load_directory(self, path): """Load directory contents into file tree.""" # Clear existing items for item in self.file_tree.get_children(): self.file_tree.delete(item) try: for item in sorted(os.listdir(path)): item_path = os.path.join(path, item) if os.path.isdir(item_path): self.file_tree.insert("", "end", text=f"📁 {item}", values=[item_path]) else: self.file_tree.insert("", "end", text=f"📄 {item}", values=[item_path]) except PermissionError: messagebox.showerror("Error", "Permission denied accessing directory") def on_file_double_click(self, event): """Handle double-click on file tree.""" selection = self.file_tree.selection() if selection: item = selection[0] file_path = self.file_tree.item(item, "values")[0] if os.path.isfile(file_path): if self.check_save_changes(): try: with open(file_path, 'r', encoding='utf-8') as file: content = file.read() self.text_editor.delete(1.0, tk.END) self.text_editor.insert(1.0, content) self.current_file = file_path self.file_modified = False self.file_label.config(text=os.path.basename(file_path)) self.update_title() self.update_outline() except Exception as e: messagebox.showerror("Error", f"Could not open file: {str(e)}") def browse_folder(self): """Browse for a folder.""" folder = filedialog.askdirectory() if folder: self.load_directory(folder) def refresh_files(self): """Refresh file list.""" # Implementation would refresh current directory pass def toggle_word_wrap(self): """Toggle word wrap in editor.""" current_wrap = self.text_editor.cget("wrap") new_wrap = tk.NONE if current_wrap == tk.WORD else tk.WORD self.text_editor.config(wrap=new_wrap) def toggle_line_numbers(self): """Toggle line numbers display.""" # Implementation would show/hide line numbers pass def exit_app(self): """Exit the application.""" if self.check_save_changes(): self.root.quit() def run(self): """Run the application.""" self.root.protocol("WM_DELETE_WINDOW", self.exit_app) self.root.mainloop() if __name__ == "__main__": app = TextEditorApp() app.run() Image Viewer Application ------------------------ A complete image viewer with thumbnail browser: .. code-block:: python import tkinter as tk from tkinter import ttk, filedialog, messagebox from PIL import Image, ImageTk import os from threepanewindows import DockableThreePaneWindow class ImageViewerApp: """A complete image viewer application.""" def __init__(self): self.root = tk.Tk() self.root.title("Professional Image Viewer") self.root.geometry("1200x800") self.current_image = None self.image_list = [] self.current_index = 0 self.setup_ui() def setup_ui(self): """Set up the user interface.""" self.create_menu() # Create dockable layout self.window = DockableThreePaneWindow( self.root, side_width=200, left_builder=self.build_thumbnail_panel, center_builder=self.build_image_viewer, right_builder=self.build_info_panel ) self.window.pack(fill=tk.BOTH, expand=True) # Status bar self.status_bar = tk.Label(self.root, text="Ready", relief=tk.SUNKEN, anchor=tk.W) self.status_bar.pack(side=tk.BOTTOM, fill=tk.X) def create_menu(self): """Create the application menu.""" menubar = tk.Menu(self.root) # File menu file_menu = tk.Menu(menubar, tearoff=0) file_menu.add_command(label="Open Image", command=self.open_image) file_menu.add_command(label="Open Folder", command=self.open_folder) file_menu.add_separator() file_menu.add_command(label="Exit", command=self.root.quit) menubar.add_cascade(label="File", menu=file_menu) # View menu view_menu = tk.Menu(menubar, tearoff=0) view_menu.add_command(label="Zoom In", command=self.zoom_in) view_menu.add_command(label="Zoom Out", command=self.zoom_out) view_menu.add_command(label="Fit to Window", command=self.fit_to_window) view_menu.add_command(label="Actual Size", command=self.actual_size) menubar.add_cascade(label="View", menu=view_menu) self.root.config(menu=menubar) def build_thumbnail_panel(self, frame): """Build the thumbnail browser panel.""" tk.Label(frame, text="đŸ–ŧī¸ Thumbnails", font=("Arial", 11, "bold")).pack(pady=5) # Thumbnail listbox self.thumbnail_listbox = tk.Listbox(frame, font=("Arial", 9)) thumb_scroll = tk.Scrollbar(frame, orient=tk.VERTICAL, command=self.thumbnail_listbox.yview) self.thumbnail_listbox.configure(yscrollcommand=thumb_scroll.set) self.thumbnail_listbox.pack(side=tk.LEFT, fill=tk.BOTH, expand=True, padx=5, pady=5) thumb_scroll.pack(side=tk.RIGHT, fill=tk.Y, pady=5) # Bind selection self.thumbnail_listbox.bind('<>', self.on_thumbnail_select) def build_image_viewer(self, frame): """Build the main image viewer panel.""" # Viewer toolbar toolbar = tk.Frame(frame, bg="#f0f0f0", height=40) toolbar.pack(fill=tk.X) toolbar.pack_propagate(False) # Navigation buttons tk.Button(toolbar, text="âŦ…ī¸ Previous", command=self.previous_image).pack(side=tk.LEFT, padx=5, pady=5) tk.Button(toolbar, text="➡ī¸ Next", command=self.next_image).pack(side=tk.LEFT, padx=5, pady=5) # Zoom controls tk.Button(toolbar, text="🔍+ Zoom In", command=self.zoom_in).pack(side=tk.LEFT, padx=5, pady=5) tk.Button(toolbar, text="🔍- Zoom Out", command=self.zoom_out).pack(side=tk.LEFT, padx=5, pady=5) tk.Button(toolbar, text="📐 Fit", command=self.fit_to_window).pack(side=tk.LEFT, padx=5, pady=5) # Image display area self.image_frame = tk.Frame(frame, bg="gray") self.image_frame.pack(fill=tk.BOTH, expand=True, padx=5, pady=5) # Canvas for image display self.image_canvas = tk.Canvas(self.image_frame, bg="white") # Scrollbars for large images v_scroll = tk.Scrollbar(self.image_frame, orient=tk.VERTICAL, command=self.image_canvas.yview) h_scroll = tk.Scrollbar(self.image_frame, orient=tk.HORIZONTAL, command=self.image_canvas.xview) self.image_canvas.configure(yscrollcommand=v_scroll.set, xscrollcommand=h_scroll.set) self.image_canvas.grid(row=0, column=0, sticky="nsew") v_scroll.grid(row=0, column=1, sticky="ns") h_scroll.grid(row=1, column=0, sticky="ew") self.image_frame.grid_rowconfigure(0, weight=1) self.image_frame.grid_columnconfigure(0, weight=1) def build_info_panel(self, frame): """Build the image information panel.""" tk.Label(frame, text="ℹī¸ Image Info", font=("Arial", 11, "bold")).pack(pady=5) # Image info display info_frame = tk.LabelFrame(frame, text="Properties", font=("Arial", 10, "bold")) info_frame.pack(fill=tk.X, padx=5, pady=5) self.info_labels = {} properties = ["Filename", "Size", "Dimensions", "Format", "Mode"] for prop in properties: prop_frame = tk.Frame(info_frame) prop_frame.pack(fill=tk.X, padx=5, pady=2) tk.Label(prop_frame, text=f"{prop}:", font=("Arial", 9), width=10, anchor="w").pack(side=tk.LEFT) self.info_labels[prop] = tk.Label(prop_frame, text="-", font=("Arial", 9), anchor="w") self.info_labels[prop].pack(side=tk.LEFT, fill=tk.X, expand=True) # Image operations def open_image(self): """Open a single image file.""" filename = filedialog.askopenfilename( title="Open Image", filetypes=[ ("Image files", "*.jpg *.jpeg *.png *.gif *.bmp *.tiff"), ("JPEG files", "*.jpg *.jpeg"), ("PNG files", "*.png"), ("All files", "*.*") ] ) if filename: self.load_image(filename) def open_folder(self): """Open a folder and load all images.""" folder = filedialog.askdirectory(title="Select Image Folder") if folder: self.load_folder(folder) def load_folder(self, folder_path): """Load all images from a folder.""" image_extensions = ('.jpg', '.jpeg', '.png', '.gif', '.bmp', '.tiff') self.image_list = [] try: for filename in os.listdir(folder_path): if filename.lower().endswith(image_extensions): self.image_list.append(os.path.join(folder_path, filename)) # Update thumbnail list self.thumbnail_listbox.delete(0, tk.END) for image_path in self.image_list: self.thumbnail_listbox.insert(tk.END, os.path.basename(image_path)) if self.image_list: self.current_index = 0 self.load_image(self.image_list[0]) self.thumbnail_listbox.selection_set(0) except Exception as e: messagebox.showerror("Error", f"Could not load folder: {str(e)}") def load_image(self, image_path): """Load and display an image.""" try: # Load image self.current_image = Image.open(image_path) self.display_image() self.update_image_info(image_path) self.status_bar.config(text=f"Loaded: {os.path.basename(image_path)}") except Exception as e: messagebox.showerror("Error", f"Could not load image: {str(e)}") def display_image(self): """Display the current image on canvas.""" if self.current_image: # Convert to PhotoImage photo = ImageTk.PhotoImage(self.current_image) # Clear canvas self.image_canvas.delete("all") # Display image self.image_canvas.create_image(0, 0, anchor=tk.NW, image=photo) self.image_canvas.image = photo # Keep a reference # Update scroll region self.image_canvas.configure(scrollregion=self.image_canvas.bbox("all")) def update_image_info(self, image_path): """Update image information display.""" if self.current_image: filename = os.path.basename(image_path) file_size = os.path.getsize(image_path) size_str = f"{file_size:,} bytes" self.info_labels["Filename"].config(text=filename) self.info_labels["Size"].config(text=size_str) self.info_labels["Dimensions"].config(text=f"{self.current_image.width} x {self.current_image.height}") self.info_labels["Format"].config(text=self.current_image.format or "Unknown") self.info_labels["Mode"].config(text=self.current_image.mode) # Navigation def previous_image(self): """Show previous image.""" if self.image_list and self.current_index > 0: self.current_index -= 1 self.load_image(self.image_list[self.current_index]) self.thumbnail_listbox.selection_clear(0, tk.END) self.thumbnail_listbox.selection_set(self.current_index) def next_image(self): """Show next image.""" if self.image_list and self.current_index < len(self.image_list) - 1: self.current_index += 1 self.load_image(self.image_list[self.current_index]) self.thumbnail_listbox.selection_clear(0, tk.END) self.thumbnail_listbox.selection_set(self.current_index) def on_thumbnail_select(self, event): """Handle thumbnail selection.""" selection = self.thumbnail_listbox.curselection() if selection and self.image_list: index = selection[0] self.current_index = index self.load_image(self.image_list[index]) # Zoom operations def zoom_in(self): """Zoom in on the image.""" if self.current_image: width, height = self.current_image.size new_width = int(width * 1.2) new_height = int(height * 1.2) self.current_image = self.current_image.resize((new_width, new_height), Image.Resampling.LANCZOS) self.display_image() def zoom_out(self): """Zoom out on the image.""" if self.current_image: width, height = self.current_image.size new_width = int(width * 0.8) new_height = int(height * 0.8) if new_width > 10 and new_height > 10: # Minimum size self.current_image = self.current_image.resize((new_width, new_height), Image.Resampling.LANCZOS) self.display_image() def fit_to_window(self): """Fit image to window size.""" # Implementation would resize image to fit canvas pass def actual_size(self): """Show image at actual size.""" if self.image_list and self.current_index < len(self.image_list): self.load_image(self.image_list[self.current_index]) def run(self): """Run the application.""" self.root.mainloop() if __name__ == "__main__": app = ImageViewerApp() app.run() Key Features of Real-World Applications --------------------------------------- These complete applications demonstrate: 1. **Professional Architecture**: Well-organized code structure 2. **Full Menu Integration**: Complete menu systems with keyboard shortcuts 3. **File Management**: Opening, saving, and managing files 4. **User Experience**: Status bars, toolbars, and responsive interfaces 5. **Error Handling**: Proper exception handling and user feedback 6. **State Management**: Tracking application state and user preferences 7. **Multi-Panel Coordination**: Panels working together seamlessly Application Patterns -------------------- Common patterns in professional applications: **Document-Based Applications** - File explorer for navigation - Main editor/viewer in center - Properties/tools on the side **Media Applications** - Thumbnail browser - Main display area - Information and controls **Development Tools** - Project explorer - Code editor - Output/debugging panels Best Practices Demonstrated --------------------------- 1. **Separation of Concerns**: UI, business logic, and data handling separated 2. **Event-Driven Architecture**: Proper event handling and callbacks 3. **User Feedback**: Status updates and error messages 4. **Keyboard Shortcuts**: Full keyboard navigation support 5. **Responsive Design**: Layouts that adapt to window resizing 6. **Professional Polish**: Attention to details like icons and styling Next Steps ---------- Use these examples as starting points for your own applications: - Modify the layouts to suit your needs - Add your own business logic - Customize the appearance and theming - Extend with additional features - Integrate with external libraries and services For more specific examples, see: - :doc:`custom_widgets` - Creating specialized panel content - :doc:`theming_examples` - Advanced styling and theming