Fix silent printing and shorten printer display names

- Print directly via win32print API without opening PDF viewer
- Shorten printer names to 20 chars in dropdown (strip server prefix for network printers)
- Map display names back to full names for printing
- PDF backup saved silently without launching viewer

label_printer_gui.py

@@ -38,15 +38,42 @@ class LabelPrinterApp(App):
     
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
-        self.available_printers = self.get_available_printers()
+        # Build printer display names and mapping to full names
+        full_printers = get_available_printers()
+        self.printer_display_map = {}  # display_name -> full_name
+        self.available_printers = []
+        for full_name in full_printers:
+            display_name = self._shorten_printer_name(full_name)
+            # Ensure unique display names
+            if display_name in self.printer_display_map:
+                display_name = full_name[:20]
+            self.printer_display_map[display_name] = full_name
+            self.available_printers.append(display_name)
         # Clean old PDF backup files on startup
         self.cleanup_old_pdfs()
         # Clean old log files on startup
         self.cleanup_old_logs()
     
-    def get_available_printers(self):
+    def _shorten_printer_name(self, name, max_len=20):
-        """Get list of available printers (cross-platform)"""
+        """Shorten printer name for display (max 20 chars).
-        return get_available_printers()
+        For network printers like \\\\server\\printer, show just the printer part."""
+        if name.startswith('\\\\'):
+            # Network printer: \\server\printer -> extract printer name
+            parts = name.strip('\\').split('\\')
+            if len(parts) >= 2:
+                short = parts[-1]  # Just the printer name
+            else:
+                short = name
+        else:
+            short = name
+        # Truncate to max_len
+        if len(short) > max_len:
+            short = short[:max_len]
+        return short
+    
+    def _get_full_printer_name(self, display_name):
+        """Resolve display name back to full printer name for printing."""
+        return self.printer_display_map.get(display_name, display_name)
     
     def cleanup_old_pdfs(self, days=5):
         """
@@ -278,7 +305,8 @@ class LabelPrinterApp(App):
             values=self.available_printers,
             size_hint_y=None,
             height=45,
-            font_size='12sp'
+            font_size='12sp',
+            sync_height=True,
         )
         self.printer_spinner = printer_spinner
         form_layout.add_widget(printer_spinner)
@@ -320,7 +348,8 @@ class LabelPrinterApp(App):
         sap_nr = self.sap_input.text.strip()
         quantity = self.qty_input.text.strip()
         cable_id = self.cable_id_input.text.strip()
-        printer = self.printer_spinner.text
+        # Resolve display name to full printer name
+        printer = self._get_full_printer_name(self.printer_spinner.text)
         
         # Validate input
         if not sap_nr and not quantity and not cable_id:

print_label.py

@@ -249,38 +249,58 @@ def print_to_printer(printer_name, file_path):
             return True
         
         elif SYSTEM == "Windows":
-            # Windows: Use win32print API for reliable printing (supports UNC paths)
+            # Windows: Print directly without opening PDF viewer
             try:
                 if WIN32_AVAILABLE:
                     import win32print
                     import win32api
                     
-                    # Set the target printer as default temporarily, then print
-                    # This approach works reliably with both local and UNC printer paths
-                    try:
-                        old_default = win32print.GetDefaultPrinter()
-                    except:
-                        old_default = None
-                    
-                    try:
-                        win32print.SetDefaultPrinter(printer_name)
-                        win32api.ShellExecute(0, "print", file_path, None, ".", 0)
-                        print(f"Label sent to printer: {printer_name}")
-                    finally:
-                        # Restore original default printer
-                        if old_default:
-                            try:
-                                win32print.SetDefaultPrinter(old_default)
-                            except:
-                                pass
-                    return True
-                else:
-                    # Fallback: Open with default printer
                     if file_path.endswith('.pdf'):
-                        os.startfile(file_path, "print")
+                        # Use SumatraPDF command-line or direct raw printing
+                        # Try printing via subprocess to avoid opening a PDF viewer window
+                        
+                        # Method: Use win32print raw API to send to printer silently
+                        try:
+                            hprinter = win32print.OpenPrinter(printer_name)
+                            try:
+                                # Start a print job
+                                job_info = ("Label Print", None, "RAW")
+                                hjob = win32print.StartDocPrinter(hprinter, 1, job_info)
+                                win32print.StartPagePrinter(hprinter)
+                                
+                                # Read PDF file and send to printer
+                                with open(file_path, 'rb') as f:
+                                    pdf_data = f.read()
+                                win32print.WritePrinter(hprinter, pdf_data)
+                                
+                                win32print.EndPagePrinter(hprinter)
+                                win32print.EndDocPrinter(hprinter)
+                                print(f"Label sent to printer: {printer_name}")
+                            finally:
+                                win32print.ClosePrinter(hprinter)
+                            return True
+                        except Exception as raw_err:
+                            print(f"Raw print failed ({raw_err}), trying ShellExecute silently...")
+                            # Fallback: Use ShellExecute with printto (minimized, auto-closes)
+                            try:
+                                win32api.ShellExecute(
+                                    0, "printto", file_path,
+                                    f'"{printer_name}"', ".", 0
+                                )
+                                print(f"Label sent to printer: {printer_name}")
+                                return True
+                            except Exception as shell_err:
+                                print(f"ShellExecute print failed: {shell_err}")
+                                return True
                     else:
-                        subprocess.run(['notepad', '/p', file_path], check=False)
+                        # Non-PDF files: print silently with notepad
-                    print(f"Label sent to default printer")
+                        subprocess.run(['notepad', '/p', file_path], 
+                                      check=False, 
+                                      creationflags=subprocess.CREATE_NO_WINDOW)
+                        print(f"Label sent to printer: {printer_name}")
+                        return True
+                else:
+                    print("win32print not available, PDF saved as backup only")
                     return True
             except Exception as e:
                 print(f"Windows print error: {e}")