Close dialogue to prevent save dialogue hidden behind qt widgets

README.md

@@ -28,6 +28,7 @@ python setup.py install
 ### Environment variables
 - BQT_DISABLE_STARTUP if set, completely disable bqt
 - BQT_DISABLE_WRAP if set to 1, disable wrapping blender in a QWindow
+- BQT_DISABLE_CLOSE_DIALOGUE if set to 1, use the standard blender close dialogue
 
 ### Sample code
 [bqt_demo](bqt_demo) shows you how to use bqt with several qt demos you can run in Blender

bqt/__init__.py

@@ -17,6 +17,7 @@
 
 
 # CORE FUNCTIONS #
+
 def instantiate_application() -> BlenderApplication:
     """
     Create an instance of Blender Application
@@ -124,3 +125,5 @@ def on_exit():
     if app:
         app.store_window_geometry()
         app.quit()
+
+

bqt/blender_applications/blender_application.py

@@ -10,6 +10,8 @@
 from PySide2.QtWidgets import QApplication, QWidget
 from PySide2.QtGui import QCloseEvent, QIcon, QImage, QPixmap, QWindow
 from PySide2.QtCore import QEvent, QObject, QRect, QSettings
+from bqt.quit_dialogue import BlenderClosingDialog
+import bpy
 
 
 class BlenderApplication(QApplication):
@@ -66,7 +68,7 @@ def _get_application_icon() -> QIcon:
         Returns QIcon: Application Icon
         """
 
-        icon_filepath = Path(__file__).parents[1] / "blender_icon_16.png"
+        icon_filepath = Path(__file__).parents[1] / "images" / "blender_icon_16.png"
         icon = QIcon()
 
         if icon_filepath.exists():
@@ -123,9 +125,14 @@ def notify(self, receiver: QObject, event: QEvent) -> bool:
             # ignore the event, and ask user if they want to close blender if unsaved changes.
             # if this is successful, blender will trigger bqt.on_exit()
             event.ignore()
-            import bpy
 
-            bpy.ops.wm.quit_blender({"window": bpy.context.window_manager.windows[0]}, "INVOKE_DEFAULT")
+            if os.getenv("BQT_DISABLE_CLOSE_DIALOGUE") == "1":
+                # this triggers the default blender close event, showing the save dialog if needed
+                bpy.ops.wm.quit_blender({"window": bpy.context.window_manager.windows[0]}, "INVOKE_DEFAULT")
+            else:
+                closing_dialog = BlenderClosingDialog(self.blender_widget)
+                closing_dialog.execute()
+
             return False
 
         return super().notify(receiver, event)

bqt/blender_stylesheet.qss

@@ -208,6 +208,13 @@ QProgressBar::chunk {
     border: 1px solid #373737;
 }
 
+QMessageBox {
+    background-color: rgb(24, 24, 24);
+}
+
+QMessageBox QPushButton {
+    min-width: 105px;
+}
 
 QPushButton {
     background-color: #585858;

bqt/quit_dialogue.py

@@ -0,0 +1,64 @@
+import bpy
+from PySide2.QtWidgets import QMessageBox
+from PySide2.QtCore import Qt
+import os
+import bqt.ui
+
+def shutdown_blender(*args):
+    bpy.ops.wm.quit_blender()
+
+
+class WINDOW_OT_SaveFileFromQt(bpy.types.Operator):
+    bl_idname = "wm.save_from_qt"
+    bl_label = "Save_from_Qt"
+
+    def execute(self, context):
+        # TODO not sure what we are doing here, Friederman?
+        if context.blend_data.is_saved:
+            bpy.ops.wm.save_mainfile({"window": bpy.context.window_manager.windows[0]}, 'EXEC_AREA', check_existing=False)
+        else:
+            bpy.ops.wm.save_mainfile({"window": bpy.context.window_manager.windows[0]}, 'INVOKE_AREA', check_existing=False)
+        # https://docs.blender.org/api/current/bpy.ops.html
+        # EXEC_AREA - execute the operator in a certain context
+        return {'FINISHED'}
+
+# todo
+#  when clicking the icon, the dialogue resets to center screen position
+#  support dragging the dialogue around
+#  add qshortcuts https://stackoverflow.com/questions/19845774/is-it-possible-to-use-an-underlined-letter-as-keyboard-shortcut-in-qt
+
+
+class BlenderClosingDialog(QMessageBox):
+    def __init__(self, parent):
+        super().__init__(parent) #, Qt.WindowCloseButtonHint | Qt.WindowSystemMenuHint | Qt.WindowTitleHint | Qt.WindowStaysOnTopHint)
+
+        # hide title bar
+        self.setWindowFlag(Qt.FramelessWindowHint)
+
+        filepath = bpy.data.filepath
+        if not filepath:
+            filepath = 'untitled.blend'
+        filename = os.path.split(filepath)[1]
+
+        question_icon = bqt.ui.get_question_pixmap()
+
+        self.setText("Save changes before closing?\n\n" + filename)
+        self.setStandardButtons(QMessageBox.Save | QMessageBox.Discard | QMessageBox.Cancel)
+        self.setDefaultButton(QMessageBox.Save)
+        self.setIconPixmap(question_icon)
+
+    def execute(self):
+        if not bpy.data.is_dirty:
+            shutdown_blender()
+            return
+
+        choice = super().exec_()
+        if choice == QMessageBox.Save:
+            bpy.utils.register_class(WINDOW_OT_SaveFileFromQt)
+            bpy.app.handlers.save_post.append(shutdown_blender)
+            bpy.ops.wm.save_from_qt()
+        elif choice == QMessageBox.Discard:
+            shutdown_blender()
+        else:  # user clicked cancel
+            pass
+        return choice

bqt/ui/__init__.py

@@ -0,0 +1,14 @@
+from pathlib import Path
+from PySide2.QtGui import QCloseEvent, QIcon, QImage, QPixmap, QWindow
+import PySide2.QtCore as QtCore
+
+
+def get_question_pixmap():
+    icon_filepath = Path(__file__).parents[1] / "images" / "question.svg"
+    pixmap = QPixmap()
+    if icon_filepath.exists():
+        image = QImage(str(icon_filepath))
+        if not image.isNull():
+            pixmap = pixmap.fromImage(image)
+            pixmap = pixmap.scaledToWidth(64, QtCore.Qt.SmoothTransformation)
+    return pixmap