Build a GUI file downloader

Here’s a complete Python example of a simple GUI file downloader using Tkinter for the interface and requests to download files from URLs. This example includes:

• Input field for the file URL

• Button to choose download location

• Button to start download

• Progress bar to show download progress

• Status label to show current status or errors

python
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import tkinter as tk
from tkinter import ttk, filedialog, messagebox
import requests
import threading
import os

class FileDownloader(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("File Downloader")
        self.geometry("500x200")
        self.resizable(False, False)

        self.url_label = tk.Label(self, text="File URL:")
        self.url_label.pack(pady=(10, 0))
        
        self.url_entry = tk.Entry(self, width=60)
        self.url_entry.pack(pady=5)

        self.path_label = tk.Label(self, text="Save to:")
        self.path_label.pack(pady=(10, 0))
        
        self.path_var = tk.StringVar()
        self.path_entry = tk.Entry(self, textvariable=self.path_var, width=50, state="readonly")
        self.path_entry.pack(side=tk.LEFT, padx=(20, 0), pady=5)
        
        self.browse_button = tk.Button(self, text="Browse", command=self.browse_folder)
        self.browse_button.pack(side=tk.LEFT, padx=10, pady=5)

        self.download_button = tk.Button(self, text="Download", command=self.start_download)
        self.download_button.pack(pady=10)

        self.progress = ttk.Progressbar(self, orient="horizontal", length=460, mode="determinate")
        self.progress.pack(pady=(0, 10))

        self.status_label = tk.Label(self, text="")
        self.status_label.pack()

    def browse_folder(self):
        folder = filedialog.askdirectory()
        if folder:
            self.path_var.set(folder)

    def start_download(self):
        url = self.url_entry.get().strip()
        save_folder = self.path_var.get().strip()

        if not url:
            messagebox.showwarning("Input Error", "Please enter a URL.")
            return
        if not save_folder:
            messagebox.showwarning("Input Error", "Please select a folder to save the file.")
            return

        self.download_button.config(state="disabled")
        self.progress["value"] = 0
        self.status_label.config(text="Starting download...")

        threading.Thread(target=self.download_file, args=(url, save_folder), daemon=True).start()

    def download_file(self, url, save_folder):
        try:
            response = requests.get(url, stream=True, timeout=10)
            response.raise_for_status()
            
            total_length = response.headers.get('content-length')
            if total_length is None:
                self.status_label.config(text="Cannot retrieve file size.")
                total_length = 0
            else:
                total_length = int(total_length)

            filename = url.split("/")[-1] or "downloaded_file"
            save_path = os.path.join(save_folder, filename)

            with open(save_path, "wb") as f:
                downloaded = 0
                for chunk in response.iter_content(chunk_size=4096):
                    if chunk:
                        f.write(chunk)
                        downloaded += len(chunk)
                        if total_length:
                            percent = int(downloaded * 100 / total_length)
                            self.progress["value"] = percent
                            self.status_label.config(text=f"Downloading... {percent}%")
                        else:
                            self.status_label.config(text=f"Downloading... {downloaded} bytes")

            self.status_label.config(text=f"Download completed: {filename}")
        except requests.exceptions.RequestException as e:
            self.status_label.config(text=f"Error: {e}")
        except Exception as e:
            self.status_label.config(text=f"Error: {e}")
        finally:
            self.download_button.config(state="normal")

if __name__ == "__main__":
    app = FileDownloader()
    app.mainloop()

How it works:

• Enter the file URL.

• Choose the folder to save the file.

• Click “Download” to start.

• Progress bar and status update during the download.

• The download runs in a separate thread to keep the GUI responsive.

Let me know if you want this extended with features like pause/resume or multiple downloads!