Android: update density on its own when it's changed

Instead of doing it every time under setDisplayMetrics().

Task-number: QTBUG-132716
Change-Id: I0887c086d7f653b0170e107a86cb0115582bbc89
Reviewed-by: Petri Virkkunen <petri.virkkunen@qt.io>

src/android/jar/src/org/qtproject/qt/android/QtActivityBase.java

@@ -179,6 +179,9 @@ public class QtActivityBase extends Activity
         if ((diff & ActivityInfo.CONFIG_LOCALE) != 0)
             QtNative.updateLocale();
 
+        if ((diff & ActivityInfo.CONFIG_DENSITY) != 0)
+            QtDisplayManager.updateScreenDensity(this);
+
         m_prevConfig = new Configuration(newConfig);
     }
 

src/android/jar/src/org/qtproject/qt/android/QtActivityDelegate.java

@@ -146,6 +146,7 @@ class QtActivityDelegate extends QtActivityDelegateBase
         handleUiModeChange(m_activity.getResources().getConfiguration().uiMode & Configuration.UI_MODE_NIGHT_MASK);
 
         QtDisplayManager.updateRefreshRate(m_activity);
+        QtDisplayManager.updateScreenDensity(m_activity);
 
         m_layout.getViewTreeObserver().addOnPreDrawListener(() -> {
             if (!m_inputDelegate.isKeyboardVisible())

src/android/jar/src/org/qtproject/qt/android/QtDisplayManager.java

@@ -6,6 +6,7 @@ package org.qtproject.qt.android;
 import android.app.Activity;
 import android.content.Context;
 import android.content.res.Configuration;
+import android.content.res.Resources;
 import android.graphics.Rect;
 import android.hardware.display.DisplayManager;
 import android.os.Build;
@@ -34,14 +35,14 @@ class QtDisplayManager {
     // screen methods
     static native void setDisplayMetrics(int screenWidthPixels, int screenHeightPixels,
                                          int availableWidthPixels, int availableHeightPixels,
-                                         double XDpi, double YDpi,
+                                         double XDpi, double YDpi);
-                                         double density);
     static native void handleOrientationChanged(int newRotation, int nativeOrientation);
     static native void handleRefreshRateChanged(float refreshRate);
     static native void handleUiDarkModeChanged(int newUiMode);
     static native void handleScreenAdded(int displayId);
     static native void handleScreenChanged(int displayId);
     static native void handleScreenRemoved(int displayId);
+    static native void handleScreenDensityChanged(double density);
     // screen methods
 
     private boolean m_isFullScreen = false;
@@ -92,6 +93,13 @@ class QtDisplayManager {
         m_previousRotation = rotation;
     }
 
+    static void updateScreenDensity(Activity activity)
+    {
+        Resources resources = activity == null ? Resources.getSystem() : activity.getResources();
+        double density = resources.getDisplayMetrics().density;
+        QtDisplayManager.handleScreenDensityChanged(density);
+    }
+
     private static int getNativeOrientation(Activity activity, int rotation)
     {
         int orientation = activity.getResources().getConfiguration().orientation;
@@ -278,13 +286,10 @@ class QtDisplayManager {
 
         final DisplayMetrics displayMetrics = activity.getResources().getDisplayMetrics();
 
-        double density = displayMetrics.density;
-
         Size displaySize = getDisplaySize(activity, QtDisplayManager.getDisplay(activity));
         setDisplayMetrics(displaySize.getWidth(), displaySize.getHeight(),
                           width, height,
-                          getXDpi(displayMetrics), getYDpi(displayMetrics),
+                          getXDpi(displayMetrics), getYDpi(displayMetrics));
-                          density);
     }
 
     static float getXDpi(final DisplayMetrics metrics) {

src/android/jar/src/org/qtproject/qt/android/QtEmbeddedDelegate.java

@@ -116,7 +116,7 @@ class QtEmbeddedDelegate extends QtActivityDelegateBase
                 QtDisplayManager.setApplicationDisplayMetrics(m_activity, metrics.widthPixels,
                                                               metrics.heightPixels);
                 QtDisplayManager.updateRefreshRate(m_activity);
-
+                QtDisplayManager.updateScreenDensity(m_activity);
             });
         }
     }

src/android/jar/src/org/qtproject/qt/android/QtServiceEmbeddedDelegate.java

@@ -44,10 +44,10 @@ class QtServiceEmbeddedDelegate implements QtEmbeddedViewInterface, QtNative.App
 
                     QtDisplayManager.setDisplayMetrics(
                             maxWidth, maxHeight, maxWidth, maxHeight,
-                            QtDisplayManager.getXDpi(metrics), QtDisplayManager.getYDpi(metrics),
+                            QtDisplayManager.getXDpi(metrics), QtDisplayManager.getYDpi(metrics));
-                            metrics.density);
 
                     QtDisplayManager.updateRefreshRate(m_service);
+                    QtDisplayManager.handleScreenDensityChanged(metrics.density);
                 });
             }
         }

src/plugins/platforms/android/androidjnimain.cpp

@@ -568,12 +568,10 @@ static void terminateQt(JNIEnv *env, jclass /*clazz*/)
 static void setDisplayMetrics(JNIEnv * /*env*/, jclass /*clazz*/,
                               jint screenWidthPixels, jint screenHeightPixels,
                               jint availableWidthPixels, jint availableHeightPixels,
-                              jdouble xdpi, jdouble ydpi,
+                              jdouble xdpi, jdouble ydpi)
-                              jdouble density)
 {
     m_availableWidthPixels = availableWidthPixels;
     m_availableHeightPixels = availableHeightPixels;
-    m_density = density;
 
     const QSize screenSize(screenWidthPixels, screenHeightPixels);
     // available geometry always starts from top left
@@ -713,6 +711,12 @@ static void handleUiDarkModeChanged(JNIEnv */*env*/, jobject /*thiz*/, jint newU
 }
 Q_DECLARE_JNI_NATIVE_METHOD(handleUiDarkModeChanged)
 
+static void handleScreenDensityChanged(JNIEnv */*env*/, jclass /*cls*/, jdouble density)
+{
+    m_density = density;
+}
+Q_DECLARE_JNI_NATIVE_METHOD(handleScreenDensityChanged)
+
 static void onActivityResult(JNIEnv */*env*/, jclass /*cls*/,
                              jint requestCode,
                              jint resultCode,
@@ -795,7 +799,8 @@ static bool registerNatives(QJniEnvironment &env)
                     Q_JNI_NATIVE_METHOD(handleScreenAdded),
                     Q_JNI_NATIVE_METHOD(handleScreenChanged),
                     Q_JNI_NATIVE_METHOD(handleScreenRemoved),
-                    Q_JNI_NATIVE_METHOD(handleUiDarkModeChanged)
+                    Q_JNI_NATIVE_METHOD(handleUiDarkModeChanged),
+                    Q_JNI_NATIVE_METHOD(handleScreenDensityChanged)
             });
 
     success = success