Minor fixes

1. Fix MainWindow example issue
2. Add a comment about the inverted argument
3. Fix some memory leaks

Signed-off-by: Yuhang Zhao <2546789017@qq.com>

examples/widget/widget.cpp

@@ -34,6 +34,7 @@
 Widget::Widget(QWidget *parent) : QtAcrylicWidget(parent)
 {
     createWinId();
+    setAcrylicEnabled(true);
     setupUi();
     startTimer(500);
 }
@@ -54,7 +55,6 @@ void Widget::showEvent(QShowEvent *event)
     static bool inited = false;
     if (!inited) {
         FramelessWindowsManager::addWindow(windowHandle());
-        setAcrylicEnabled(true);
         inited = true;
     }
 }

qtacryliceffecthelper_win32.cpp

@@ -106,10 +106,13 @@ bool QtAcrylicWinEventFilter::nativeEventFilter(const QByteArray &eventType, voi
             shouldUpdate = true;
         }
     } break;
+    case WM_DPICHANGED: {
+        shouldClearWallpaper = true;
+        shouldUpdate = true;
+    } break;
     case WM_THEMECHANGED:
     case WM_DWMCOMPOSITIONCHANGED:
     case WM_DWMCOLORIZATIONCOLORCHANGED:
-    case WM_DPICHANGED:
         shouldUpdate = true;
         break;
     default :

qtacrylicmainwindow.cpp

@@ -165,6 +165,7 @@ void QtAcrylicMainWindow::showEvent(QShowEvent *event)
         m_acrylicHelper.install(windowHandle());
         m_acrylicHelper.updateAcrylicBrush(tintColor());
         connect(&m_acrylicHelper, &QtAcrylicEffectHelper::needsRepaint, this, qOverload<>(&QtAcrylicMainWindow::update));
+        Utilities::setBlurEffectEnabled(windowHandle(), m_acrylicEnabled);
         m_inited = true;
     }
 }

qtacrylicwidget.cpp

@@ -164,6 +164,7 @@ void QtAcrylicWidget::showEvent(QShowEvent *event)
         m_acrylicHelper.install(windowHandle());
         m_acrylicHelper.updateAcrylicBrush(tintColor());
         connect(&m_acrylicHelper, &QtAcrylicEffectHelper::needsRepaint, this, qOverload<>(&QtAcrylicWidget::update));
+        Utilities::setBlurEffectEnabled(windowHandle(), m_acrylicEnabled);
         m_inited = true;
     }
 }

utilities.cpp

@@ -165,6 +165,8 @@ static inline void expblur(QImage &img, const qreal radius, const bool improvedQ
             qt_blurrow<aprec, zprec, alphaOnly>(img, row, alpha);
         }
     }
+    // TODO: QImage(int width, int height, QImage::Format format)
+    // Why the argument order is inverted here?
     QImage temp(img.height(), img.width(), img.format());
     temp.setDevicePixelRatio(img.devicePixelRatio());
     if (transposed >= 0) {

utilities_win32.cpp

@@ -514,8 +514,12 @@ QImage Utilities::getDesktopWallpaperImage(const int screen)
                     if (SUCCEEDED(pDesktopWallpaper->GetMonitorDevicePathAt(monitorIndex, &monitorId)) && monitorId) {
                         LPWSTR wallpaperPath = nullptr;
                         if (SUCCEEDED(pDesktopWallpaper->GetWallpaper(monitorId, &wallpaperPath)) && wallpaperPath) {
-                            return QImage(QString::fromWCharArray(wallpaperPath));
+                            CoTaskMemFree(monitorId);
+                            const QString _path = QString::fromWCharArray(wallpaperPath);
+                            CoTaskMemFree(wallpaperPath);
+                            return QImage(_path);
                         } else {
+                            CoTaskMemFree(monitorId);
                             qWarning() << "IDesktopWallpaper::GetWallpaper() failed.";
                         }
                     } else {
@@ -543,10 +547,12 @@ QImage Utilities::getDesktopWallpaperImage(const int screen)
         });
 #endif
         if (SUCCEEDED(CoCreateInstance(CLSID_ActiveDesktop, nullptr, CLSCTX_INPROC_SERVER, IID_IActiveDesktop, reinterpret_cast<void **>(&pActiveDesktop))) && pActiveDesktop) {
-            WCHAR wallpaperPath[MAX_PATH] = {};
+            const auto wallpaperPath = new WCHAR[MAX_PATH];
             // TODO: AD_GETWP_BMP, AD_GETWP_IMAGE, AD_GETWP_LAST_APPLIED. What's the difference?
             if (SUCCEEDED(pActiveDesktop->GetWallpaper(wallpaperPath, MAX_PATH, AD_GETWP_LAST_APPLIED))) {
-                return QImage(QString::fromWCharArray(wallpaperPath));
+                const QString _path = QString::fromWCharArray(wallpaperPath);
+                delete [] wallpaperPath;
+                return QImage(_path);
             } else {
                 qWarning() << "IActiveDesktop::GetWallpaper() failed.";
             }
@@ -559,7 +565,9 @@ QImage Utilities::getDesktopWallpaperImage(const int screen)
     qDebug() << "Shell API failed. Using SystemParametersInfoW instead.";
     LPWSTR wallpaperPath = nullptr;
     if (SystemParametersInfoW(SPI_GETDESKWALLPAPER, MAX_PATH, wallpaperPath, 0) != FALSE) {
-        return QImage(QString::fromWCharArray(wallpaperPath));
+        const QString _path = QString::fromWCharArray(wallpaperPath);
+        CoTaskMemFree(wallpaperPath);
+        return QImage(_path);
     }
     qWarning() << "SystemParametersInfoW failed. Reading from the registry instead.";
     const QSettings settings(g_desktopRegistryKey, QSettings::NativeFormat);