PySide6: Add a Designer plugin

Add a convencience class QPyDesignerCustomWidgetCollection to
the Qt Designer module, which provides functions for
registering widget types or adding QDesignerCustomWidgetInterface
instances. A static instance of it is stored as a dynamic
property on QCoreApplication, which is retrieved by a Qt Designer
plugin, which provides the collection of widgets registered in
Python.

Task-number: PYSIDE-1455
Change-Id: If4055e6c9db6a03b32016b013a1130051bbd472a
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>

1 files changed, 18 insertions, 0 deletions

diff --git a/sources/pyside-tools/pyside_tool.py b/sources/pyside-tools/pyside_tool.py
index 485520f5d..c49b05054 100644
--- a/sources/pyside-tools/pyside_tool.py
+++ b/sources/pyside-tools/pyside_tool.py
@@ -40,6 +40,7 @@
 #############################################################################
 import sys
 import os
+from pathlib import Path
 import subprocess
 
 from subprocess import Popen, PIPE
@@ -79,7 +80,24 @@ def rcc():
     qt_tool_wrapper("rcc", ['-g', 'python'] + sys.argv[1:])
 
 
+def _append_to_path_var(var, value):
+    env_value = os.environ.get(var)
+    if env_value:
+        env_value = f'{env_value}{os.pathsep}{value}'
+    else:
+        env_value = value
+    os.environ[var] = env_value
+
+
 def designer():
+    # Add the examples to PYSIDE_DESIGNER_PLUGINS, as determined by starting from
+    # PySide6/scripts.
+    pyside_dir = Path(__file__).resolve().parents[1]
+
+    # Add the Wiggly Widget example
+    wiggly_dir = os.fspath(pyside_dir / 'examples' / 'widgetbinding')
+    _append_to_path_var('PYSIDE_DESIGNER_PLUGINS', wiggly_dir)
+
     if sys.platform == "darwin":
         qt_tool_wrapper("Designer.app/Contents/MacOS/Designer", sys.argv[1:])
     else: