PdfMultiPageView: use TableView; horz. scroll; control page position

TableView is missing some features compared to ListView; so finding out
where we currently are (which row) and programmatic positioning on a
specific y coordinate of a specific row require some workarounds for now,
including helpers in PdfDocument.

TableView also assumes (and sporadically enforces) that all cells in a
column have the same width.  So we need a placeholder Item for each page.
This also helps with rotation: the placeholder is now as wide as the
window or the image, whichever is wider, and the "paper" is centered
within; thus there's always room to rotate it.

There's still some problem with setting contentY in goToPage() after
the page has been zoomed to a size larger than the window: the values
look correct, but it scrolls too far.

But on the plus side, horizontal scrolling works.  So now we attempt to
control the horizontal position too: NavigationStack tracks it, and can
go back to a previous position; and links can in theory jump to specific
positions and zoom levels, scrolling horizontally such that a specific x
coordinate is visible.

Includes minor UI tweaks to make it look better on iOS.

Change-Id: I643d8ef48ef815aeb49cae77dcb84c3682563d56
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

1 files changed, 7 insertions, 0 deletions

diff --git a/src/pdf/quick/qquickpdfdocument_p.h b/src/pdf/quick/qquickpdfdocument_p.h
index 9817b5eef..cefa4f756 100644
--- a/src/pdf/quick/qquickpdfdocument_p.h
+++ b/src/pdf/quick/qquickpdfdocument_p.h
@@ -62,6 +62,8 @@ class QQuickPdfDocument : public QObject, public QQmlParserStatus
     Q_OBJECT
     Q_PROPERTY(QUrl source READ source WRITE setSource NOTIFY sourceChanged)
     Q_PROPERTY(int pageCount READ pageCount NOTIFY pageCountChanged FINAL)
+    Q_PROPERTY(qreal maxPageWidth READ maxPageWidth NOTIFY metaDataChanged)
+    Q_PROPERTY(qreal maxPageHeight READ maxPageHeight NOTIFY metaDataChanged)
     Q_PROPERTY(QString password READ password WRITE setPassword NOTIFY passwordChanged FINAL)
     Q_PROPERTY(QPdfDocument::Status status READ status NOTIFY statusChanged FINAL)
     Q_PROPERTY(QString error READ error NOTIFY statusChanged FINAL)
@@ -102,6 +104,9 @@ public:
     QDateTime modificationDate() { return m_doc.metaData(QPdfDocument::ModificationDate).toDateTime(); }
 
     Q_INVOKABLE QSizeF pagePointSize(int page) const;
+    qreal maxPageWidth() const;
+    qreal maxPageHeight() const;
+    Q_INVOKABLE qreal heightSumBeforePage(int page, qreal spacing = 0, int facingPages = 1) const;
 
 Q_SIGNALS:
     void sourceChanged();
@@ -113,10 +118,12 @@ Q_SIGNALS:
 
 private:
     QPdfDocument &document() { return m_doc; }
+    void updateMaxPageSize();
 
 private:
     QUrl m_source;
     QPdfDocument m_doc;
+    QSizeF m_maxPageWidthHeight;
 
     friend class QQuickPdfLinkModel;
     friend class QQuickPdfSearchModel;