Windows: fixed wrong layout in maximized frame after changing screen scale factor (issue #904)

Windows binaries built and signed locally in clean workspace

CHANGELOG.md

@@ -10,6 +10,8 @@ FlatLaf Change Log
 - FlatLaf window decorations:
   - Windows: Fixed possible deadlock with TabbedPane in window title area in
     "full window content" mode. (issue #909)
+  - Windows: Fixed wrong layout in maximized frame after changing screen scale
+    factor. (issue #904)
   - Linux: Fixed continuous cursor toggling between resize and standard cursor
     when resizing window. (issue #907)
 

flatlaf-natives/flatlaf-natives-jna/src/main/java/com/formdev/flatlaf/natives/jna/windows/FlatWindowsNativeWindowBorder.java

@@ -309,6 +309,8 @@ public class FlatWindowsNativeWindowBorder
 			WM_ENTERSIZEMOVE = 0x0231,
 			WM_EXITSIZEMOVE = 0x0232,
 
+			WM_DPICHANGED = 0x02E0,
+
 			WM_DWMCOLORIZATIONCOLORCHANGED = 0x0320;
 
 		// WM_SIZE wParam
@@ -501,6 +503,22 @@ public class FlatWindowsNativeWindowBorder
 						isMoving = true;
 					break;
 
+				case WM_DPICHANGED:
+					LRESULT lResult = User32Ex.INSTANCE.CallWindowProc( defaultWndProc, hwnd, uMsg, wParam, lParam );
+
+					// if window is maximized and DPI/scaling changed, then Windows
+					// does not send a subsequent WM_SIZE message and Java window bounds,
+					// which depend on scale factor, are not updated
+					boolean isMaximized = User32Ex.INSTANCE.IsZoomed( hwnd );
+					if( isMaximized ) {
+						MyRECT r = new MyRECT( new Pointer( lParam.longValue() ) );
+						int width = r.right - r.left;
+						int height = r.bottom - r.top;
+						User32Ex.INSTANCE.CallWindowProc( defaultWndProc, hwnd, WM_SIZE, new WPARAM( SIZE_MAXIMIZED ), MAKELPARAM( width, height ) );
+					}
+
+					return lResult;
+
 				case WM_ERASEBKGND:
 					// do not erase background while the user is moving the window,
 					// otherwise there may be rendering artifacts on HiDPI screens with Java 9+
@@ -818,6 +836,13 @@ public class FlatWindowsNativeWindowBorder
 			return (low & 0xffff) | ((high & 0xffff) << 16);
 		}
 
+		/**
+		 * Same implementation as MAKELPARAM(l, h) macro in winuser.h.
+		 */
+		private LPARAM MAKELPARAM( int low, int high ) {
+			return new LPARAM( MAKELONG( low, high ) );
+		}
+
 		/**
 		 * Same implementation as RGB(r,g,b) macro in wingdi.h.
 		 */
@@ -937,6 +962,23 @@ public class FlatWindowsNativeWindowBorder
 		}
 	}
 
+	//---- class MyRECT -------------------------------------------------------
+
+	@FieldOrder( { "left", "top", "right", "bottom" } )
+	public static class MyRECT
+		extends Structure
+	{
+		public int left;
+		public int top;
+		public int right;
+		public int bottom;
+
+		public MyRECT( Pointer pointer ) {
+			super( pointer );
+			read();
+		}
+	}
+
 	//---- class MENUITEMINFO -------------------------------------------------
 
 	@FieldOrder( { "cbSize", "fMask", "fType", "fState", "wID", "hSubMenu",

flatlaf-natives/flatlaf-natives-windows/README.md

@@ -19,3 +19,32 @@ The DLLs were built on a GitHub server with the help of GitHub Actions. See:
 [Native Libraries](https://github.com/JFormDesigner/FlatLaf/actions/workflows/natives.yml)
 workflow. Then the produced Artifacts ZIP was downloaded, signed DLLs with
 FormDev Software code signing certificate and committed the DLLs to Git.
+
+
+## Development
+
+To build the library on Windows using Gradle, (parts of)
+[Visual Studio Community
+2022](https://visualstudio.microsoft.com/downloads/)
+needs to be installed. After downloading and running `VisualStudioSetup.exe` the
+**Visual Studio Installer** is installed and started. Once running, it shows the
+**Workloads** tab that allows you to install additional packages. Either choose
+**Desktop development with C++**, or to save some disk space switch to the
+**Single Components** tab and choose following components (newest versions):
+
+- MSVC v143 - VS 2022 C++ x64/x86 Buildtools
+- MSVC v143 - VS 2022 C++ ARM64/ARM64EC Buildtools
+- Windows 11 SDK
+
+Note that the Visual Studio Installer shows many similar named components for
+MSVC. Make sure to choose exactly those components listed above.
+
+Using
+[Build Tools for Visual Studio 2022](https://visualstudio.microsoft.com/downloads/#remote-tools-for-visual-studio-2022)
+(installs only compiler and SDKs) instead of
+[Visual Studio Community
+2022](https://visualstudio.microsoft.com/downloads/)
+does not work with Gradle.
+
+[Visual Studio Code](https://code.visualstudio.com/) with **C/C++** extension
+can be used for C++ code editing.

flatlaf-natives/flatlaf-natives-windows/src/main/cpp/FlatWndProc.cpp

@@ -288,6 +288,23 @@ LRESULT CALLBACK FlatWndProc::WindowProc( HWND hwnd, UINT uMsg, WPARAM wParam, L
 				isMoving = true;
 			break;
 
+		case WM_DPICHANGED: {
+			LRESULT lResult = ::CallWindowProc( defaultWndProc, hwnd, uMsg, wParam, lParam );
+
+			// if window is maximized and DPI/scaling changed, then Windows
+			// does not send a subsequent WM_SIZE message and Java window bounds,
+			// which depend on scale factor, are not updated
+			bool isMaximized = ::IsZoomed( hwnd );
+			if( isMaximized ) {
+				RECT* r = reinterpret_cast<RECT*>( lParam );
+				int width = r->right - r->left;
+				int height = r->bottom - r->top;
+				::CallWindowProc( defaultWndProc, hwnd, WM_SIZE, SIZE_MAXIMIZED, MAKELPARAM( width, height ) );
+			}
+
+			return lResult;
+		}
+
 		case WM_ERASEBKGND:
 			// do not erase background while the user is moving the window,
 			// otherwise there may be rendering artifacts on HiDPI screens with Java 9+

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowDecorationsTest.java

@@ -25,6 +25,8 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Random;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicReference;
 import javax.swing.*;
 import javax.swing.border.TitledBorder;
 import com.formdev.flatlaf.FlatClientProperties;
@@ -74,6 +76,7 @@ public class FlatWindowDecorationsTest
 	}
 
 	private List<Image> images;
+	private Timer refreshStateTimer;
 
 	FlatWindowDecorationsTest() {
 		initComponents();
@@ -132,6 +135,49 @@ public class FlatWindowDecorationsTest
 				fullWindowContentButtonsBoundsField.setEnabled( bounds != null );
 			} );
 		}
+
+		if( window instanceof Frame ) {
+			AtomicInteger lastState = new AtomicInteger( -1 );
+			AtomicReference<Window> lastFullScreenWindow = new AtomicReference<>();
+			refreshStateTimer = new Timer( 500, e -> {
+				Frame frame = (Frame) window;
+				int state = frame.getExtendedState();
+				Window fullScreenWindow = window.getGraphicsConfiguration().getDevice().getFullScreenWindow();
+				if( state != lastState.get() || fullScreenWindow != lastFullScreenWindow.get() ) {
+					lastState.set( state );
+					lastFullScreenWindow.set( fullScreenWindow );
+
+					String s = "";
+					if( (state & Frame.ICONIFIED) != 0 )
+						s += "iconified ";
+					if( (state & Frame.MAXIMIZED_BOTH) == Frame.MAXIMIZED_BOTH )
+						s += "maximized ";
+					else {
+						if( (state & Frame.MAXIMIZED_HORIZ) != 0 )
+							s += "maximized-horizontal ";
+						if( (state & Frame.MAXIMIZED_VERT) != 0 )
+							s += "maximized-vertical ";
+					}
+					if( fullScreenWindow == window )
+						s += "full-screen ";
+					if( s.isEmpty() )
+						s = "normal";
+
+					frameStateField.setText( s );
+				}
+			} );
+			refreshStateTimer.start();
+		}
+	}
+
+	@Override
+	public void removeNotify() {
+		super.removeNotify();
+
+		if( refreshStateTimer != null ) {
+			refreshStateTimer.stop();
+			refreshStateTimer = null;
+		}
 	}
 
 	private void updateDecorationStyleRadioButtons( JRootPane rootPane ) {
@@ -653,6 +699,9 @@ debug*/
 		typeUtilityRadioButton = new JRadioButton();
 		typeSmallRadioButton = new JRadioButton();
 		showRectanglesCheckBox = new JCheckBox();
+		JPanel hSpacer1 = new JPanel(null);
+		JLabel frameStateLabel = new JLabel();
+		frameStateField = new JLabel();
 		menuBar = new JMenuBar();
 		JMenu fileMenu = new JMenu();
 		JMenuItem newMenuItem = new JMenuItem();
@@ -1092,6 +1141,16 @@ debug*/
 		showRectanglesCheckBox.setSelected(true);
 		showRectanglesCheckBox.addActionListener(e -> showRectangles());
 		add(showRectanglesCheckBox, "cell 0 3");
+		add(hSpacer1, "cell 2 3 2 1");
+
+		//---- frameStateLabel ----
+		frameStateLabel.setText("Frame state:");
+		add(frameStateLabel, "cell 2 3 2 1,alignx right,growx 0");
+
+		//---- frameStateField ----
+		frameStateField.setText("n/a");
+		frameStateField.setFont(frameStateField.getFont().deriveFont(frameStateField.getFont().getStyle() | Font.BOLD));
+		add(frameStateField, "cell 2 3 2 1,alignx right,growx 0");
 
 		//======== menuBar ========
 		{
@@ -1341,6 +1400,7 @@ debug*/
 	private JRadioButton typeUtilityRadioButton;
 	private JRadioButton typeSmallRadioButton;
 	private JCheckBox showRectanglesCheckBox;
+	private JLabel frameStateField;
 	private JMenuBar menuBar;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 }

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatWindowDecorationsTest.jfd

@@ -637,6 +637,27 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 0 3"
 			} )
+			add( new FormComponent( "com.jformdesigner.designer.wrapper.HSpacer" ) {
+				name: "hSpacer1"
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 2 3 2 1"
+			} )
+			add( new FormComponent( "javax.swing.JLabel" ) {
+				name: "frameStateLabel"
+				"text": "Frame state:"
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 2 3 2 1,alignx right,growx 0"
+			} )
+			add( new FormComponent( "javax.swing.JLabel" ) {
+				name: "frameStateField"
+				"text": "n/a"
+				"font": new com.jformdesigner.model.SwingDerivedFont( null, 1, 0, false )
+				auxiliary() {
+					"JavaCodeGenerator.variableLocal": false
+				}
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 2 3 2 1,alignx right,growx 0"
+			} )
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
 			"size": new java.awt.Dimension( 960, 570 )

gradle/libs.versions.toml

@@ -46,8 +46,8 @@ glazedlists = "com.glazedlists:glazedlists:1.11.0"
 netbeans-api-awt = "org.netbeans.api:org-openide-awt:RELEASE112"
 
 # flatlaf-natives-jna
-jna = "net.java.dev.jna:jna:5.12.1"
+jna = "net.java.dev.jna:jna:5.15.0"
-jna-platform = "net.java.dev.jna:jna-platform:5.12.1"
+jna-platform = "net.java.dev.jna:jna-platform:5.15.0"
 
 # junit
 junit = { module = "org.junit.jupiter:junit-jupiter", version.ref = "junit" }