Move currentFrame and frameCount properties up to QQuickImageBase

AnimatedImage already had these properties, but some typically non-animated
image formats such as PDF, TIFF and ICO can also support multiple pages.
In either case, the currentFrame property can be used to select a specific
frame or page.  However an AnimatedImage uses a QMovie to do that, whereas
a plain Image uses QQuickPixmap.  So the accessors need to be virtual in
order to have these different implementations.

[ChangeLog][QtQuick][Image] Image and BorderImage now have currentFrame
and frameCount properties which can be used to step through the frames of
multi-page image formats such as TIFF, WEBP and ICO.

Task-number: QTBUG-77506
Change-Id: Id4d95a99a26a862957e44b1bd8ffe06d7eababef
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>

1 files changed, 36 insertions, 1 deletions

diff --git a/src/quick/items/qquickimagebase.cpp b/src/quick/items/qquickimagebase.cpp
index 40857964a9..8bab14bfd1 100644
--- a/src/quick/items/qquickimagebase.cpp
+++ b/src/quick/items/qquickimagebase.cpp
@@ -211,6 +211,36 @@ bool QQuickImageBase::mirror() const
     return d->mirror;
 }
 
+void QQuickImageBase::setCurrentFrame(int frame)
+{
+    Q_D(QQuickImageBase);
+    if (frame == d->currentFrame || frame < 0 || (isComponentComplete() && frame >= d->pix.frameCount()))
+        return;
+
+    d->currentFrame = frame;
+
+    if (isComponentComplete()) {
+        if (frame > 0)
+            d->cache = false;
+        load();
+        update();
+    }
+
+    emit currentFrameChanged();
+}
+
+int QQuickImageBase::currentFrame() const
+{
+    Q_D(const QQuickImageBase);
+    return d->currentFrame;
+}
+
+int QQuickImageBase::frameCount() const
+{
+    Q_D(const QQuickImageBase);
+    return d->frameCount;
+}
+
 void QQuickImageBase::load()
 {
     Q_D(QQuickImageBase);
@@ -261,7 +291,7 @@ void QQuickImageBase::load()
             resolve2xLocalFile(d->url, targetDevicePixelRatio, &loadUrl, &d->devicePixelRatio);
         }
 
-        d->pix.load(qmlEngine(this), loadUrl, d->sourcesize * d->devicePixelRatio, options, d->providerOptions);
+        d->pix.load(qmlEngine(this), loadUrl, d->sourcesize * d->devicePixelRatio, options, d->providerOptions, d->currentFrame, d->frameCount);
 
         if (d->pix.isLoading()) {
             if (d->progress != 0.0) {
@@ -320,6 +350,11 @@ void QQuickImageBase::requestFinished()
         d->oldAutoTransform = autoTransform();
         emitAutoTransformBaseChanged();
     }
+    if (d->frameCount != d->pix.frameCount()) {
+        d->frameCount = d->pix.frameCount();
+        emit frameCountChanged();
+    }
+
     update();
 }