Android: fix missing wheel events

Change-Id: I65b4f6a8fcbdad537a984064e332a4a1f34a265a
Task-number: QTBUG-43669
Reviewed-by: BogDan Vatra <bogdan@kdab.com>

src/android/jar/src/org/qtproject/qt5/android/QtNative.java

@@ -61,6 +61,7 @@ import android.view.KeyEvent;
 import android.view.Menu;
 import android.view.MotionEvent;
 import android.view.View;
+import android.view.InputDevice;
 
 import java.lang.reflect.Method;
 import java.security.KeyStore;
@@ -470,6 +471,17 @@ public class QtNative
         }
     }
 
+    static public void sendGenericMotionEvent(MotionEvent event, int id)
+    {
+        if (event.getActionMasked() != MotionEvent.ACTION_SCROLL
+                || (event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != InputDevice.SOURCE_CLASS_POINTER) {
+            return;
+        }
+
+        mouseWheel(id, (int) event.getX(), (int) event.getY(),
+                       event.getAxisValue(MotionEvent.AXIS_HSCROLL), event.getAxisValue(MotionEvent.AXIS_VSCROLL));
+    }
+
     public static Context getContext() {
         if (m_activity != null)
             return m_activity;
@@ -801,6 +813,7 @@ public class QtNative
     public static native void mouseDown(int winId, int x, int y);
     public static native void mouseUp(int winId, int x, int y);
     public static native void mouseMove(int winId, int x, int y);
+    public static native void mouseWheel(int winId, int x, int y, float hdelta, float vdelta);
     public static native void touchBegin(int winId);
     public static native void touchAdd(int winId, int pointerId, int action, boolean primary, int x, int y, float major, float minor, float rotation, float pressure);
     public static native void touchEnd(int winId, int action);

src/android/jar/src/org/qtproject/qt5/android/QtSurface.java

@@ -112,4 +112,11 @@ public class QtSurface extends SurfaceView implements SurfaceHolder.Callback
         QtNative.sendTrackballEvent(event, getId());
         return true;
     }
+
+    @Override
+    public boolean onGenericMotionEvent(MotionEvent event)
+    {
+        QtNative.sendGenericMotionEvent(event, getId());
+        return true;
+    }
 }

src/plugins/platforms/android/androidjniinput.cpp

@@ -173,6 +173,25 @@ namespace QtAndroidInput
                                                  Qt::MouseButtons(Qt::LeftButton));
     }
 
+    static void mouseWheel(JNIEnv */*env*/, jobject /*thiz*/, jint /*winId*/, jint x, jint y, jfloat hdelta, jfloat vdelta)
+    {
+        if (m_ignoreMouseEvents)
+            return;
+
+        QPoint globalPos(x,y);
+        QWindow *tlw = m_mouseGrabber.data();
+        if (!tlw)
+            tlw = topLevelWindowAt(globalPos);
+        QPoint localPos = tlw ? (globalPos-tlw->position()) : globalPos;
+        QPoint angleDelta(hdelta * 120, vdelta * 120);
+
+        QWindowSystemInterface::handleWheelEvent(tlw,
+                                                 localPos,
+                                                 globalPos,
+                                                 QPoint(),
+                                                 angleDelta);
+    }
+
     static void longPress(JNIEnv */*env*/, jobject /*thiz*/, jint /*winId*/, jint x, jint y)
     {
         QAndroidInputContext *inputContext = QAndroidInputContext::androidInputContext();
@@ -824,6 +843,7 @@ namespace QtAndroidInput
         {"mouseDown", "(III)V", (void *)mouseDown},
         {"mouseUp", "(III)V", (void *)mouseUp},
         {"mouseMove", "(III)V", (void *)mouseMove},
+        {"mouseWheel", "(IIIFF)V", (void *)mouseWheel},
         {"longPress", "(III)V", (void *)longPress},
         {"isTabletEventSupported", "()Z", (void *)isTabletEventSupported},
         {"tabletEvent", "(IIJIIIFFF)V", (void *)tabletEvent},