SplitView: fix hidden items causing visible items to not be resizable

When a handle is dragged, the items on either side of it are resized.
Until this patch, we were assuming that the item after the
one at the handle index was visible, which was wrong. Now we iterate
through each item after the one at the pressed index until we find
one that's visible. Since we need this in a few other places during
a handle drag, we cache it as a member variable.

This patch also fixes an issue where the visibility of handles were
not updated after setting a new handle delegate.

Change-Id: Icd246abae2ed4dc6c3b81217b9a241b7e4debf7d
Fixes: QTBUG-81867
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

1 files changed, 69 insertions, 1 deletions

diff --git a/tests/auto/controls/data/tst_splitview.qml b/tests/auto/controls/data/tst_splitview.qml
index 74e4c68e..ae8179b2 100644
--- a/tests/auto/controls/data/tst_splitview.qml
+++ b/tests/auto/controls/data/tst_splitview.qml
@@ -148,6 +148,7 @@ TestCase {
             color: "#444"
 
             Text {
+                objectName: "handleText_" + text
                 text: parent.x + "," + parent.y + " " + parent.width + "x" + parent.height
                 color: "white"
                 anchors.centerIn: parent
@@ -871,6 +872,42 @@ TestCase {
         }
     }
 
+    Component {
+        id: hiddenItemSplitViewComponent
+
+        SplitView {
+            anchors.fill: parent
+            handle: handleComponent
+
+            Rectangle {
+                objectName: "steelblue"
+                color: objectName
+
+                SplitView.minimumWidth: 50
+            }
+            Rectangle {
+                objectName: "tomato"
+                color: objectName
+
+                SplitView.fillWidth: true
+                SplitView.preferredWidth: 200
+            }
+            Rectangle {
+                objectName: "navajowhite"
+                color: objectName
+                visible: false
+
+                SplitView.minimumWidth: visible ? 100 : 0
+            }
+            Rectangle {
+                objectName: "mediumseagreen"
+                color: objectName
+
+                SplitView.minimumWidth: 50
+            }
+        }
+    }
+
     function test_dragHandle_data() {
         var splitViewWidth = testCase.width - splitViewMargins * 2
         var splitViewHeight = testCase.height - splitViewMargins * 2
@@ -1151,6 +1188,36 @@ TestCase {
                     { x: 140, y: 0, width: defaultHorizontalHandleWidth, height: splitViewHeight },
                     { x: 150, y: 0, width: 150, height: splitViewHeight }
                 ]
+            },
+            {
+                tag: "hiddenItemSplitViewComponent",
+                // [50] | [200 (fill)] | [hidden] | [50]
+                component: hiddenItemSplitViewComponent,
+                orientation: Qt.Horizontal,
+                fillIndex: 1,
+                handleIndex: 1,
+                // Drag to the horizontal centre of the SplitView.
+                newHandlePos: Qt.point(splitViewMargins + 150, testCase.height / 2),
+                expectedGeometriesBeforeDrag: [
+                    { x: 0, y: 0, width: 50, height: splitViewHeight },
+                    { x: 50, y: 0, width: defaultHorizontalHandleWidth, height: splitViewHeight },
+                    { x: 50 + defaultHorizontalHandleWidth, y: 0, width: 200 - defaultHorizontalHandleWidth * 2, height: splitViewHeight },
+                    { x: 250 - (defaultHorizontalHandleWidth * 2) + defaultHorizontalHandleWidth, y: 0, width: defaultHorizontalHandleWidth, height: splitViewHeight },
+                    { hidden: true }, // Third item should be hidden.
+                    { hidden: true }, // Handle for third item should be hidden.
+                    { x: 250 - (defaultHorizontalHandleWidth * 2) + defaultHorizontalHandleWidth * 2, y: 0, width: 50, height: splitViewHeight }
+                ],
+                expectedGeometriesAfterDrag: [
+                    { x: 0, y: 0, width: 50, height: splitViewHeight },
+                    { x: 50, y: 0, width: defaultHorizontalHandleWidth, height: splitViewHeight },
+                    // Width of the fill item should end up smaller.
+                    { x: 50 + defaultHorizontalHandleWidth, y: 0, width: 100 - defaultHorizontalHandleWidth * 2, height: splitViewHeight },
+                    { x: 150 - (defaultHorizontalHandleWidth * 2) + defaultHorizontalHandleWidth, y: 0, width: defaultHorizontalHandleWidth, height: splitViewHeight },
+                    { hidden: true }, // Third item should be hidden.
+                    { hidden: true }, // Handle for third item should be hidden.
+                    // Width of the last item should grow.
+                    { x: 150 - (defaultHorizontalHandleWidth * 2) + defaultHorizontalHandleWidth * 2, y: 0, width: 150, height: splitViewHeight }
+                ]
             }
         ]
         return data
@@ -1171,7 +1238,7 @@ TestCase {
         else
             fillItem.SplitView.fillHeight = true
 
-        // Check the sizes of the items before the drag.
+        // Check the sizes (and visibility) of the items before the drag.
         verify(isPolishScheduled(control))
         verify(waitForItemPolished(control))
         compareSizes(control, data.expectedGeometriesBeforeDrag, "before drag")
@@ -1179,6 +1246,7 @@ TestCase {
         // Drag the handle.
         var handles = findHandles(control)
         var targetHandle = handles[data.handleIndex]
+        verify(targetHandle.visible)
         mousePress(targetHandle)
         verify(control.resizing)
         // newHandlePos is in scene coordinates, so map it to coordinates local to the handle.