Android: Fix screen flicker issues

When changing focus between TextInput fields there is a flicker of the QQuickWidget

Fixes: QTBUG-66727
Change-Id: I9f31f43dee1bbbf213422978a35e752a8ceff56c
Reviewed-by: Rami Potinkara <rami.potinkara@qt.io>

3 files changed, 35 insertions, 9 deletions

diff --git a/src/android/jar/src/org/qtproject/qt5/android/QtLayout.java b/src/android/jar/src/org/qtproject/qt5/android/QtLayout.java
index f22b8176c8..45b5c0b061 100644
--- a/src/android/jar/src/org/qtproject/qt5/android/QtLayout.java
+++ b/src/android/jar/src/org/qtproject/qt5/android/QtLayout.java
@@ -46,10 +46,13 @@ import android.util.AttributeSet;
 import android.util.DisplayMetrics;
 import android.view.View;
 import android.view.ViewGroup;
+import android.graphics.Rect;
 
 public class QtLayout extends ViewGroup
 {
     private Runnable m_startApplicationRunnable;
+    private int m_bottomDisplayFrame = -1;
+
     public QtLayout(Context context, Runnable startRunnable)
     {
         super(context);
@@ -66,13 +69,30 @@ public class QtLayout extends ViewGroup
         super(context, attrs, defStyle);
     }
 
-    @Override
-    protected void onSizeChanged (int w, int h, int oldw, int oldh)
+    private void handleSizeChanged (int w, int h, int oldw, int oldh)
     {
         DisplayMetrics metrics = new DisplayMetrics();
         ((Activity) getContext()).getWindowManager().getDefaultDisplay().getMetrics(metrics);
-        QtNative.setApplicationDisplayMetrics(metrics.widthPixels, metrics.heightPixels, w, h,
-                                              metrics.xdpi, metrics.ydpi, metrics.scaledDensity, metrics.density);
+
+        Rect r = new Rect();
+        ((Activity) getContext()).getWindow().getDecorView().getWindowVisibleDisplayFrame(r);
+
+        if (m_bottomDisplayFrame !=  r.bottom) {
+            m_bottomDisplayFrame =  r.bottom;
+            QtNative.setApplicationDisplayMetrics(metrics.widthPixels, metrics.heightPixels, w, h,
+                                                metrics.xdpi,
+                                                metrics.ydpi,
+                                                metrics.scaledDensity,
+                                                metrics.density,
+                                                ((metrics.heightPixels == h) || (metrics.heightPixels == h + r.top)));
+        }
+    }
+
+    @Override
+    protected void onSizeChanged (int w, int h, int oldw, int oldh)
+    {
+        handleSizeChanged (w, h, oldw, oldh);
+
         if (m_startApplicationRunnable != null) {
             m_startApplicationRunnable.run();
             m_startApplicationRunnable = null;
@@ -150,6 +170,8 @@ public class QtLayout extends ViewGroup
 
             }
         }
+
+        handleSizeChanged (r, b, 0, 0);
     }
 
     // Override to allow type-checking of LayoutParams.
diff --git a/src/android/jar/src/org/qtproject/qt5/android/QtNative.java b/src/android/jar/src/org/qtproject/qt5/android/QtNative.java
index c1210ab5b6..b31ed3577e 100644
--- a/src/android/jar/src/org/qtproject/qt5/android/QtNative.java
+++ b/src/android/jar/src/org/qtproject/qt5/android/QtNative.java
@@ -612,7 +612,8 @@ public class QtNative
                                       m_displayMetricsXDpi,
                                       m_displayMetricsYDpi,
                                       m_displayMetricsScaledDensity,
-                                      m_displayMetricsDensity);
+                                      m_displayMetricsDensity,
+                                      true);
                 }
             });
             m_qtThread.post(new Runnable() {
@@ -634,7 +635,8 @@ public class QtNative
                                                     double XDpi,
                                                     double YDpi,
                                                     double scaledDensity,
-                                                    double density)
+                                                    double density,
+                                                    boolean forceUpdate)
     {
         /* Fix buggy dpi report */
         if (XDpi < android.util.DisplayMetrics.DENSITY_LOW)
@@ -651,7 +653,8 @@ public class QtNative
                                   XDpi,
                                   YDpi,
                                   scaledDensity,
-                                  density);
+                                  density,
+                                  forceUpdate);
             } else {
                 m_displayMetricsScreenWidthPixels = screenWidthPixels;
                 m_displayMetricsScreenHeightPixels = screenHeightPixels;
@@ -1354,7 +1357,8 @@ public class QtNative
                                                 double XDpi,
                                                 double YDpi,
                                                 double scaledDensity,
-                                                double density);
+                                                double density,
+                                                boolean forceUpdate);
     public static native void handleOrientationChanged(int newRotation, int nativeOrientation);
     // screen methods
 
diff --git a/src/android/jar/src/org/qtproject/qt5/android/QtServiceDelegate.java b/src/android/jar/src/org/qtproject/qt5/android/QtServiceDelegate.java
index 1da377c2ba..68e79c273f 100644
--- a/src/android/jar/src/org/qtproject/qt5/android/QtServiceDelegate.java
+++ b/src/android/jar/src/org/qtproject/qt5/android/QtServiceDelegate.java
@@ -115,7 +115,7 @@ public class QtServiceDelegate
         QtNative.setService(m_service, this);
         QtNative.setClassLoader(classLoader);
 
-        QtNative.setApplicationDisplayMetrics(10, 10, 10, 10, 120, 120, 1.0, 1.0);
+        QtNative.setApplicationDisplayMetrics(10, 10, 10, 10, 120, 120, 1.0, 1.0, false);
 
         if (loaderParams.containsKey(STATIC_INIT_CLASSES_KEY)) {
             for (String className: loaderParams.getStringArray(STATIC_INIT_CLASSES_KEY)) {