Create new "Zoom to 100%" action

Summary:
This patch implements a "Zoom to 100%" action and sticks it in the {nav View} menu. Since it's a `KStandardAction` with a `KStandardShortcut`, we automatically get the correct icon and keyboard shortcut, but we do override the name to be "Zoom to 100%" since that's clearer for Okular's use case.

FEATURE: 400048
FIXED-IN: 18.12.0

Test Plan:
- Action works to zoom the document to 100% scale when invoked
- Action is disabled when document is opened at 100% scale or is manually zoomed to 100% scale after being opened
- All other zoom modes and action still work

{F6341045}

Reviewers: #okular, #vdg, abetts

Reviewed By: #vdg, abetts

Subscribers: davidhurka, sander, tobiasdeiminger, veqz, abetts, aacid, okular-devel

Tags: #okular

Differential Revision: https://phabricator.kde.org/D16345

part-viewermode.rc

@@ -1,5 +1,5 @@
 <!DOCTYPE kpartgui SYSTEM "kpartgui.dtd">
-<kpartgui name="okular_part_viewermode" version="3">
+<kpartgui name="okular_part_viewermode" version="4">
 
 <MenuBar>
   <Menu name="file"><text>&amp;File</text>
@@ -22,6 +22,7 @@
   <Separator group="viewer_menu_merge"/>
   <Action name="view_zoom_in" group="viewer_menu_merge"/>
   <Action name="view_zoom_out" group="viewer_menu_merge"/>
+  <Action name="view_actual_size" group="viewer_menu_merge"/>
   <Action name="view_fit_to_width" group="viewer_menu_merge"/>
   <Action name="view_fit_to_page" group="viewer_menu_merge"/>
   <Separator group="viewer_menu_merge"/>

part.rc

@@ -1,5 +1,5 @@
 <!DOCTYPE kpartgui SYSTEM "kpartgui.dtd">
-<kpartgui name="okular_part" version="38">
+<kpartgui name="okular_part" version="39">
 <MenuBar>
   <Menu name="file"><text>&amp;File</text>
     <Action name="get_new_stuff" group="file_open"/>
@@ -31,6 +31,7 @@
     <Separator/>
     <Action name="view_zoom_in"/>
     <Action name="view_zoom_out"/>
+    <Action name="view_actual_size"/>
     <Action name="view_fit_to_width"/>
     <Action name="view_fit_to_page"/>
     <Action name="view_auto_fit"/>

ui/pageview.cpp

@@ -222,6 +222,7 @@ public:
     KSelectAction * aZoom;
     QAction * aZoomIn;
     QAction * aZoomOut;
+    QAction * aZoomActual;
     KToggleAction * aZoomFitWidth;
     KToggleAction * aZoomFitPage;
     KToggleAction * aZoomAutoFit;
@@ -483,6 +484,9 @@ void PageView::setupBaseActions( KActionCollection * ac )
     d->aZoomIn = KStandardAction::zoomIn( this, SLOT(slotZoomIn()), ac );
 
     d->aZoomOut = KStandardAction::zoomOut( this, SLOT(slotZoomOut()), ac );
+
+    d->aZoomActual = KStandardAction::actualSize( this, &PageView::slotZoomActual, ac );
+    d->aZoomActual->setText(i18n("Zoom to 100%"));
 }
 
 void PageView::setupViewerActions( KActionCollection * ac )
@@ -1204,6 +1208,8 @@ void PageView::updateActionState( bool haspages, bool documentChanged, bool hasf
         d->aZoomIn->setEnabled( haspages );
     if ( d->aZoomOut )
         d->aZoomOut->setEnabled( haspages );
+    if ( d->aZoomActual )
+        d->aZoomActual->setEnabled( haspages && d->zoomFactor != 1.0 );
 
     if ( d->mouseModeActionGroup )
         d->mouseModeActionGroup->setEnabled( haspages );
@@ -4001,6 +4007,10 @@ void PageView::updateZoom( ZoomMode newZoomMode )
             }
             }
             break;
+        case ZoomActual:
+            newZoomMode = ZoomFixed;
+            newFactor = 1.0;
+            break;
         case ZoomFitWidth:
             checkedZoomAction = d->aZoomFitWidth;
             break;
@@ -4048,6 +4058,7 @@ void PageView::updateZoom( ZoomMode newZoomMode )
 
     d->aZoomIn->setEnabled( d->zoomFactor < upperZoomLimit-0.001 );
     d->aZoomOut->setEnabled( d->zoomFactor > 0.101 );
+    d->aZoomActual->setEnabled( d->zoomFactor != 1.0 );
 }
 
 void PageView::updateZoomText()
@@ -4978,6 +4989,11 @@ void PageView::slotZoomOut()
     updateZoom( ZoomOut );
 }
 
+void PageView::slotZoomActual()
+{
+    updateZoom( ZoomActual );
+}
+
 void PageView::slotFitToWidthToggled( bool on )
 {
     if ( on ) updateZoom( ZoomFitWidth );

ui/pageview.h

@@ -62,9 +62,9 @@ Q_OBJECT
         PageView( QWidget *parent, Okular::Document *document );
         ~PageView();
 
-        // Zoom mode ( last 3 are internally used only! )
+        // Zoom mode ( last 4 are internally used only! )
         enum ZoomMode { ZoomFixed = 0, ZoomFitWidth = 1, ZoomFitPage = 2, ZoomFitAuto = 3,
-                        ZoomIn, ZoomOut, ZoomRefreshCurrent };
+                        ZoomIn, ZoomOut, ZoomRefreshCurrent, ZoomActual };
 
         enum ClearMode { ClearAllSelection, ClearOnlyDividers };
 
@@ -237,6 +237,7 @@ Q_OBJECT
         void slotZoom();
         void slotZoomIn();
         void slotZoomOut();
+        void slotZoomActual();
         void slotFitToWidthToggled( bool );
         void slotFitToPageToggled( bool );
         void slotAutoFitToggled( bool );