Android: Implement QInputMethod::keyboardRectangle

We can use getWindowVisibleDisplayFrame to know the height on the
keyboard, and we can use getLocationOnScreen to find out how much
the view is scrolled. Since onPreDraw is always called when the
view is scrolled or when the keyboard appears or disapear, we can
call the native functions from there.

This is not working for floating keyboards.

[ChangeLog][Android] Implemented QInputMethod::keyboardRectangle

Task-number: QTBUG-40731
Change-Id: I7848eb34fece410b29a06bf0bbb2313112fffa68
Reviewed-by: Samuel Nevala <samuel.nevala@intopalo.com>
Reviewed-by: BogDan Vatra <bogdan@kdab.com>

3 files changed, 33 insertions, 3 deletions

diff --git a/src/plugins/platforms/android/androidjniinput.cpp b/src/plugins/platforms/android/androidjniinput.cpp
index 8982787ec9..9cc5e95378 100644
--- a/src/plugins/platforms/android/androidjniinput.cpp
+++ b/src/plugins/platforms/android/androidjniinput.cpp
@@ -51,6 +51,7 @@ namespace QtAndroidInput
 
     static bool m_ignoreMouseEvents = false;
     static bool m_softwareKeyboardVisible = false;
+    static QRect m_softwareKeyboardRect;
 
     static QList<QWindowSystemInterface::TouchPoint> m_touchPoints;
 
@@ -108,6 +109,11 @@ namespace QtAndroidInput
         return m_softwareKeyboardVisible;
     }
 
+    QRect softwareKeyboardRect()
+    {
+        return m_softwareKeyboardRect;
+    }
+
 
     static void mouseDown(JNIEnv */*env*/, jobject /*thiz*/, jint /*winId*/, jint x, jint y)
     {
@@ -734,14 +740,35 @@ namespace QtAndroidInput
     static void keyboardVisibilityChanged(JNIEnv */*env*/, jobject /*thiz*/, jboolean visibility)
     {
         m_softwareKeyboardVisible = visibility;
+        if (!visibility)
+            m_softwareKeyboardRect = QRect();
+
         QAndroidInputContext *inputContext = QAndroidInputContext::androidInputContext();
-        if (inputContext && qGuiApp)
+        if (inputContext && qGuiApp) {
             inputContext->emitInputPanelVisibleChanged();
+            if (!visibility)
+                inputContext->emitKeyboardRectChanged();
+        }
 #ifdef QT_DEBUG_ANDROID_IM_PROTOCOL
         qDebug() << "@@@ KEYBOARDVISIBILITYCHANGED" << inputContext;
 #endif
     }
 
+    static void keyboardGeometryChanged(JNIEnv */*env*/, jobject /*thiz*/, jint x, jint y, jint w, jint h)
+    {
+        QRect r = QRect(x, y, w, h);
+        if (r == m_softwareKeyboardRect)
+            return;
+        m_softwareKeyboardRect = r;
+        QAndroidInputContext *inputContext = QAndroidInputContext::androidInputContext();
+        if (inputContext && qGuiApp)
+            inputContext->emitKeyboardRectChanged();
+
+#ifdef QT_DEBUG_ANDROID_IM_PROTOCOL
+        qDebug() << "@@@ KEYBOARDRECTCHANGED" << m_softwareKeyboardRect;
+#endif
+    }
+
     static JNINativeMethod methods[] = {
         {"touchBegin","(I)V",(void*)touchBegin},
         {"touchAdd","(IIIZIIFF)V",(void*)touchAdd},
@@ -753,7 +780,8 @@ namespace QtAndroidInput
         {"tabletEvent", "(IIJIIIFFF)V", (void *)tabletEvent},
         {"keyDown", "(IIIZ)V", (void *)keyDown},
         {"keyUp", "(IIIZ)V", (void *)keyUp},
-        {"keyboardVisibilityChanged", "(Z)V", (void *)keyboardVisibilityChanged}
+        {"keyboardVisibilityChanged", "(Z)V", (void *)keyboardVisibilityChanged},
+        {"keyboardGeometryChanged", "(IIII)V", (void *)keyboardGeometryChanged}
     };
 
     bool registerNatives(JNIEnv *env)
diff --git a/src/plugins/platforms/android/androidjniinput.h b/src/plugins/platforms/android/androidjniinput.h
index d737dc9c98..7132d1fc4e 100644
--- a/src/plugins/platforms/android/androidjniinput.h
+++ b/src/plugins/platforms/android/androidjniinput.h
@@ -35,6 +35,7 @@
 #define ANDROIDJNIINPUT_H
 #include <jni.h>
 #include <QtCore/qglobal.h>
+#include <QtCore/QRect>
 
 QT_BEGIN_NAMESPACE
 
@@ -45,6 +46,7 @@ namespace QtAndroidInput
     void resetSoftwareKeyboard();
     void hideSoftwareKeyboard();
     bool isSoftwareKeyboardVisible();
+    QRect softwareKeyboardRect();
     void updateSelection(int selStart, int selEnd, int candidatesStart, int candidatesEnd);
     // Software keyboard support
 
diff --git a/src/plugins/platforms/android/qandroidinputcontext.cpp b/src/plugins/platforms/android/qandroidinputcontext.cpp
index e3ea048e84..0eddb26959 100644
--- a/src/plugins/platforms/android/qandroidinputcontext.cpp
+++ b/src/plugins/platforms/android/qandroidinputcontext.cpp
@@ -512,7 +512,7 @@ void QAndroidInputContext::invokeAction(QInputMethod::Action action, int cursorP
 
 QRectF QAndroidInputContext::keyboardRect() const
 {
-    return QPlatformInputContext::keyboardRect();
+    return QtAndroidInput::softwareKeyboardRect();
 }
 
 bool QAndroidInputContext::isAnimating() const