PdfSearchModel: be QALM and find search results on all pages

It's a QAbstractListModel, so now PdfMultiPageView has a ListView in a
left-side Drawer showing all results found so far.

- In PdfMultiPageView, multiple pages exist at once, so it makes sense
  to use the same searchmodel for all.
- It's faster and saves memory.
- Search results on each page can be cached.
- It's possible to show search results in a ListView or QListView.

Change-Id: I66fba6975954a09a4d23262be87ff8cc25ee7478
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

2 files changed, 55 insertions, 60 deletions

diff --git a/src/pdf/quick/qml/PdfMultiPageView.qml b/src/pdf/quick/qml/PdfMultiPageView.qml
index bc5134267..b64f44576 100644
--- a/src/pdf/quick/qml/PdfMultiPageView.qml
+++ b/src/pdf/quick/qml/PdfMultiPageView.qml
@@ -104,39 +104,10 @@ Item {
     }
 
     // text search
+    property alias searchModel: searchModel
     property alias searchString: searchModel.searchString
-    property bool searchBackEnabled: searchModel.currentResult > 0
-    property bool searchForwardEnabled: searchModel.currentResult < searchModel.matchGeometry.length - 1
-    function searchBack() {
-        if (searchModel.currentResult > 0) {
-            --searchModel.currentResult
-        } else {
-            searchModel.deferRendering = true // save time while we are searching
-            while (searchModel.currentResult <= 0) {
-                if (navigationStack.currentPage > 0)
-                    goToPage(navigationStack.currentPage - 1)
-                else
-                    goToPage(document.pageCount - 1)
-                searchModel.currentResult = searchModel.matchGeometry.length - 1
-            }
-            searchModel.deferRendering = false
-        }
-    }
-    function searchForward() {
-        if (searchModel.currentResult < searchModel.matchGeometry.length - 1) {
-            ++searchModel.currentResult
-        } else {
-            searchModel.deferRendering = true // save time while we are searching
-            while (searchModel.currentResult >= searchModel.matchGeometry.length - 1) {
-                searchModel.currentResult = 0
-                if (navigationStack.currentPage < document.pageCount - 1)
-                    goToPage(navigationStack.currentPage + 1)
-                else
-                    goToPage(0)
-            }
-            searchModel.deferRendering = false
-        }
-    }
+    function searchBack() { --searchModel.currentResult }
+    function searchForward() { ++searchModel.currentResult }
 
     id: root
     ListView {
@@ -159,7 +130,7 @@ Item {
             property real pageScale: image.paintedWidth / pagePointSize.width
             Image {
                 id: image
-                source: searchModel.deferRendering ? "" : document.source
+                source: document.source
                 currentFrame: index
                 asynchronous: true
                 fillMode: Image.PreserveAspectFit
@@ -178,31 +149,36 @@ Item {
             Shape {
                 anchors.fill: parent
                 opacity: 0.25
-                visible: image.status === Image.Ready && searchModel.page == index
+                visible: image.status === Image.Ready
                 ShapePath {
                     strokeWidth: 1
-                    strokeColor: "steelblue"
-                    fillColor: "lightsteelblue"
+                    strokeColor: "cyan"
+                    fillColor: "steelblue"
                     scale: Qt.size(paper.pageScale, paper.pageScale)
                     PathMultiline {
-                        paths: searchModel.matchGeometry
+                        paths: searchModel.boundingPolygonsOnPage(index)
                     }
                 }
                 ShapePath {
-                    strokeWidth: 1
-                    strokeColor: "blue"
-                    fillColor: "cyan"
+                    fillColor: "orange"
                     scale: Qt.size(paper.pageScale, paper.pageScale)
-                    PathPolyline {
-                        path: searchModel.matchGeometry[searchModel.currentResult]
+                    PathMultiline {
+                        id: selectionBoundaries
+                        paths: selection.geometry
                     }
                 }
+            }
+            Shape {
+                anchors.fill: parent
+                opacity: 0.5
+                visible: image.status === Image.Ready && searchModel.currentPage === index
                 ShapePath {
-                    fillColor: "orange"
+                    strokeWidth: 1
+                    strokeColor: "blue"
+                    fillColor: "cyan"
                     scale: Qt.size(paper.pageScale, paper.pageScale)
                     PathMultiline {
-                        id: selectionBoundaries
-                        paths: selection.geometry
+                        paths: searchModel.currentResultBoundingPolygons
                     }
                 }
             }
@@ -297,7 +273,10 @@ Item {
     PdfNavigationStack {
         id: navigationStack
         onJumped: listView.currentIndex = page
-        onCurrentPageChanged: listView.positionViewAtIndex(currentPage, ListView.Beginning)
+        onCurrentPageChanged: {
+            listView.positionViewAtIndex(currentPage, ListView.Beginning)
+            searchModel.currentPage = currentPage
+        }
         onCurrentLocationChanged: listView.contentY += currentLocation.y // currentPageChanged() MUST occur first!
         onCurrentZoomChanged: root.renderScale = currentZoom
         // TODO deal with horizontal location (need another Flickable probably)
@@ -305,9 +284,6 @@ Item {
     PdfSearchModel {
         id: searchModel
         document: root.document === undefined ? null : root.document
-        page: navigationStack.currentPage
-        searchString: root.searchString
-        property int currentResult: 0
-        property bool deferRendering: false
+        onCurrentPageChanged: root.goToPage(currentPage)
     }
 }
diff --git a/src/pdf/quick/qml/PdfPageView.qml b/src/pdf/quick/qml/PdfPageView.qml
index d03e9dc9d..f4d7da0af 100644
--- a/src/pdf/quick/qml/PdfPageView.qml
+++ b/src/pdf/quick/qml/PdfPageView.qml
@@ -50,15 +50,18 @@ Rectangle {
     property alias sourceSize: image.sourceSize
     property alias currentPage: navigationStack.currentPage
     property alias pageCount: image.frameCount
-    property alias searchString: searchModel.searchString
     property alias selectedText: selection.text
     property alias status: image.status
     property alias backEnabled: navigationStack.backAvailable
     property alias forwardEnabled: navigationStack.forwardAvailable
     function back() { navigationStack.back() }
     function forward() { navigationStack.forward() }
-    function goToPage(page) { navigationStack.push(page, Qt.point(0, 0), renderScale) }
-    signal currentPageReallyChanged(page: int)
+    function goToPage(page) { goToLocation(page, Qt.point(0, 0), 0) }
+    function goToLocation(page, location, zoom) {
+        if (zoom > 0)
+            paper.renderScale = zoom
+        navigationStack.push(page, location, zoom)
+    }
 
     property real __pageScale: image.paintedWidth / document.pagePointSize(navigationStack.currentPage).width
 
@@ -107,6 +110,12 @@ Rectangle {
         paper.scale = 1
     }
 
+    // text search
+    property alias searchModel: searchModel
+    property alias searchString: searchModel.searchString
+    function searchBack() { --searchModel.currentResult }
+    function searchForward() { ++searchModel.currentResult }
+
     PdfSelection {
         id: selection
         document: paper.document
@@ -121,13 +130,16 @@ Rectangle {
 
     PdfSearchModel {
         id: searchModel
-        document: paper.document
-        page: navigationStack.currentPage
+        document: paper.document === undefined ? null : paper.document
+        currentPage: navigationStack.currentPage
+        onCurrentPageChanged: paper.goToPage(currentPage)
     }
 
     PdfNavigationStack {
         id: navigationStack
-        onCurrentPageChanged: paper.currentPageReallyChanged(navigationStack.currentPage)
+        // TODO onCurrentLocationChanged: position currentLocation.x and .y in middle // currentPageChanged() MUST occur first!
+        onCurrentZoomChanged: paper.renderScale = currentZoom
+        // TODO deal with horizontal location (need WheelHandler or Flickable probably)
     }
 
     Image {
@@ -168,19 +180,26 @@ Rectangle {
         visible: image.status === Image.Ready
         ShapePath {
             strokeWidth: 1
-            strokeColor: "blue"
+            strokeColor: "cyan"
+            fillColor: "steelblue"
+            scale: Qt.size(paper.__pageScale, paper.__pageScale)
+            PathMultiline {
+                paths: searchModel.currentPageBoundingPolygons
+            }
+        }
+        ShapePath {
+            strokeWidth: 1
+            strokeColor: "orange"
             fillColor: "cyan"
             scale: Qt.size(paper.__pageScale, paper.__pageScale)
             PathMultiline {
-                id: searchResultBoundaries
-                paths: searchModel.matchGeometry
+                paths: searchModel.currentResultBoundingPolygons
             }
         }
         ShapePath {
             fillColor: "orange"
             scale: Qt.size(paper.__pageScale, paper.__pageScale)
             PathMultiline {
-                id: selectionBoundaries
                 paths: selection.geometry
             }
         }