Ensure AnimatedImage currentFrame/onCurrentFrameChanged 2.0 compatibility

Change 5d995ae122aa07486ead849560b74d2b62b883bb did not make the actual
QQuickImageBase::currentFrameChanged signal accessible to the Qt Quick
2.0 revision. Normally the QML engine would implement a JS
onCurrentFrameChanged handler by connecting to the currentFrame
property's frameChanged notifier signal; but in this case it tried to
connect to the explicit QQuickImageBase::currentFrameChanged signal
instead (because the name is a better match), and failed because of the
revision. So we need another duplicate unrevisioned signal
QQuickAnimatedImage::currentFrameChanged for use when the import is less
than Qt Quick 2.14.

As pointed out during review, an autotest for the revisioning is good to
have anyway.

Fixes: QTBUG-78713
Task-number: QTBUG-77506
Change-Id: I121508acac81d47e3c0a4c0ed12257c10b30970b
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

4 files changed, 62 insertions, 1 deletions

diff --git a/src/quick/items/qquickanimatedimage.cpp b/src/quick/items/qquickanimatedimage.cpp
index bebefc1b22..18d492cd68 100644
--- a/src/quick/items/qquickanimatedimage.cpp
+++ b/src/quick/items/qquickanimatedimage.cpp
@@ -140,6 +140,7 @@ QQuickAnimatedImage::QQuickAnimatedImage(QQuickItem *parent)
 {
     connect(this, &QQuickImageBase::cacheChanged, this, &QQuickAnimatedImage::onCacheChanged);
     connect(this, &QQuickImageBase::currentFrameChanged, this, &QQuickAnimatedImage::frameChanged);
+    connect(this, &QQuickImageBase::currentFrameChanged, this, &QQuickAnimatedImage::currentFrameChanged);
     connect(this, &QQuickImageBase::frameCountChanged, this, &QQuickAnimatedImage::frameCountChanged);
 }
 
@@ -466,7 +467,7 @@ void QQuickAnimatedImage::movieUpdate()
 
     if (d->movie) {
         d->setPixmap(*d->infoForCurrentFrame(qmlEngine(this)));
-        emit currentFrameChanged();
+        emit QQuickImageBase::currentFrameChanged();
     }
 }
 
diff --git a/src/quick/items/qquickanimatedimage_p.h b/src/quick/items/qquickanimatedimage_p.h
index ef5af6b387..13eae83350 100644
--- a/src/quick/items/qquickanimatedimage_p.h
+++ b/src/quick/items/qquickanimatedimage_p.h
@@ -101,6 +101,7 @@ Q_SIGNALS:
     void playingChanged();
     void pausedChanged();
     void frameChanged();
+    void currentFrameChanged();
     void frameCountChanged();
     Q_REVISION(11) void speedChanged();
 
diff --git a/tests/auto/quick/qquickanimatedimage/data/currentframe.qml b/tests/auto/quick/qquickanimatedimage/data/currentframe.qml
new file mode 100644
index 0000000000..b679da2a99
--- /dev/null
+++ b/tests/auto/quick/qquickanimatedimage/data/currentframe.qml
@@ -0,0 +1,13 @@
+import QtQuick 2.0
+
+AnimatedImage {
+    property int currentFrameChangeCount: 0
+    property int frameChangeCount: 0
+    source: "stickman.gif"
+    onCurrentFrameChanged: if (currentFrame > 0) ++currentFrameChangeCount;
+    onFrameChanged: if (currentFrame > 0) ++frameChangeCount;
+    function scriptedSetCurrentFrame(frame) {
+        currentFrame = frame;
+    }
+}
+
diff --git a/tests/auto/quick/qquickanimatedimage/tst_qquickanimatedimage.cpp b/tests/auto/quick/qquickanimatedimage/tst_qquickanimatedimage.cpp
index 8026bafb9e..31c3fb9946 100644
--- a/tests/auto/quick/qquickanimatedimage/tst_qquickanimatedimage.cpp
+++ b/tests/auto/quick/qquickanimatedimage/tst_qquickanimatedimage.cpp
@@ -27,6 +27,7 @@
 ****************************************************************************/
 #include <qtest.h>
 #include <QtQml/qqmlengine.h>
+#include <QtQml/qqmlexpression.h>
 #include <QtQml/qqmlcomponent.h>
 #include <QtQuick/qquickview.h>
 #include <QtQuick/private/qquickrectangle_p.h>
@@ -40,6 +41,23 @@
 
 Q_DECLARE_METATYPE(QQuickImageBase::Status)
 
+template <typename T> static T evaluate(QObject *scope, const QString &expression)
+{
+    QQmlExpression expr(qmlContext(scope), scope, expression);
+    QVariant result = expr.evaluate();
+    if (expr.hasError())
+        qWarning() << expr.error().toString();
+    return result.value<T>();
+}
+
+template <> void evaluate<void>(QObject *scope, const QString &expression)
+{
+    QQmlExpression expr(qmlContext(scope), scope, expression);
+    expr.evaluate();
+    if (expr.hasError())
+        qWarning() << expr.error().toString();
+}
+
 class tst_qquickanimatedimage : public QQmlDataTest
 {
     Q_OBJECT
@@ -68,6 +86,7 @@ private slots:
     void playingAndPausedChanges();
     void noCaching();
     void sourceChangesOnFrameChanged();
+    void currentFrame();
 };
 
 void tst_qquickanimatedimage::cleanup()
@@ -618,6 +637,33 @@ void tst_qquickanimatedimage::sourceChangesOnFrameChanged()
     qDeleteAll(images);
 }
 
+void tst_qquickanimatedimage::currentFrame()
+{
+    QQuickView window;
+    window.setSource(testFileUrl("currentframe.qml"));
+    window.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&window));
+
+    QQuickAnimatedImage *anim = qobject_cast<QQuickAnimatedImage *>(window.rootObject());
+    QVERIFY(anim);
+    QSignalSpy frameChangedSpy(anim, SIGNAL(frameChanged()));
+    QSignalSpy currentFrameChangedSpy(anim, SIGNAL(currentFrameChanged()));
+
+    anim->setCurrentFrame(1);
+    QCOMPARE(anim->currentFrame(), 1);
+    QCOMPARE(frameChangedSpy.count(), 1);
+    QCOMPARE(currentFrameChangedSpy.count(), 1);
+    QCOMPARE(anim->property("currentFrameChangeCount"), 1);
+    QCOMPARE(anim->property("frameChangeCount"), 1);
+
+    evaluate<void>(anim, "scriptedSetCurrentFrame(2)");
+    QCOMPARE(anim->currentFrame(), 2);
+    QCOMPARE(frameChangedSpy.count(), 2);
+    QCOMPARE(currentFrameChangedSpy.count(), 2);
+    QCOMPARE(anim->property("currentFrameChangeCount"), 2);
+    QCOMPARE(anim->property("frameChangeCount"), 2);
+}
+
 QTEST_MAIN(tst_qquickanimatedimage)
 
 #include "tst_qquickanimatedimage.moc"