diff options
| author | Gabriel de Dietrich <gabriel.dedietrich@theqtcompany.com> | 2015-09-02 13:51:45 +0200 |
|---|---|---|
| committer | Gabriel de Dietrich <gabriel.dedietrich@theqtcompany.com> | 2015-10-30 13:00:01 +0000 |
| commit | afbf1fcb251c1f751758f62317f1cd9795b79310 (patch) | |
| tree | 5a20f01711379ebca54c4c03430783ece475a460 /src/controls/ScrollView.qml | |
| parent | 2e48d16e4a230069884ac0585ae111037f4171fb (diff) | |
ScrollView: Don't depend on originY for the internal scrollbar
While originY (and originX) are always zero for Flickable,
other types, like ListView, can and will set its value as
items are added or removed from the view. However, having
the internal scrollbars depend on originY may cause extra
updates and interfere with ListView transitions.
This changes just hardcodes the scrollbar's minimum value
to 0 and translates its value by originY. We also made the
code in ScrollViewHelper a bit more readable, mostly by
renaming the top-level item's id from 'wheelArea' to
'scrollHelper'.
Change-Id: Iac0b4e1dc3ca50ff3cc50fbb85ccaf1eca88edba
Task-number: QTBUG-48044
Reviewed-by: Mitch Curtis <mitch.curtis@theqtcompany.com>
Diffstat (limited to 'src/controls/ScrollView.qml')
| -rw-r--r-- | src/controls/ScrollView.qml | 27 |
1 files changed, 14 insertions, 13 deletions
diff --git a/src/controls/ScrollView.qml b/src/controls/ScrollView.qml index 74d5ee7dd..e6001b041 100644 --- a/src/controls/ScrollView.qml +++ b/src/controls/ScrollView.qml @@ -238,13 +238,13 @@ FocusScope { onContentYChanged: { scroller.blockUpdates = true - scroller.verticalScrollBar.value = flickableItem.contentY + scroller.verticalScrollBar.value = flickableItem.contentY - flickableItem.originY scroller.blockUpdates = false } onContentXChanged: { scroller.blockUpdates = true - scroller.horizontalScrollBar.value = flickableItem.contentX + scroller.horizontalScrollBar.value = flickableItem.contentX - flickableItem.originX scroller.blockUpdates = false } @@ -274,11 +274,11 @@ FocusScope { property bool horizontalRecursionGuard: false property bool verticalRecursionGuard: false - horizontalMinimumValue: flickableItem ? flickableItem.originX : 0 - horizontalMaximumValue: flickableItem ? flickableItem.originX + flickableItem.contentWidth - viewport.width : 0 + horizontalMinimumValue: 0 + horizontalMaximumValue: flickableItem ? flickableItem.contentWidth - viewport.width : 0 - verticalMinimumValue: flickableItem ? flickableItem.originY : 0 - verticalMaximumValue: flickableItem ? flickableItem.originY + flickableItem.contentHeight - viewport.height + __viewTopMargin : 0 + verticalMinimumValue: 0 + verticalMaximumValue: flickableItem ? flickableItem.contentHeight - viewport.height + __viewTopMargin : 0 // The default scroll speed for typical angle-based mouse wheels. The value // comes originally from QTextEdit, which sets 20px steps by default, as well as @@ -291,32 +291,33 @@ FocusScope { onContentYChanged: { wheelArea.verticalRecursionGuard = true - wheelArea.verticalValue = flickableItem.contentY + wheelArea.verticalValue = flickableItem.contentY - flickableItem.originY wheelArea.verticalRecursionGuard = false } onContentXChanged: { wheelArea.horizontalRecursionGuard = true - wheelArea.horizontalValue = flickableItem.contentX + wheelArea.horizontalValue = flickableItem.contentX - flickableItem.originX wheelArea.horizontalRecursionGuard = false } } onVerticalValueChanged: { if (!verticalRecursionGuard) { - if (flickableItem.contentY < flickThreshold && verticalDelta > speedThreshold) { + var effectiveContentY = flickableItem.contentY - flickableItem.originY + if (effectiveContentY < flickThreshold && verticalDelta > speedThreshold) { flickableItem.flick(ignored, Math.min(maxFlick, acceleration * verticalDelta)) - } else if (flickableItem.contentY > flickableItem.contentHeight - - flickThreshold - viewport.height && verticalDelta < -speedThreshold) { + } else if (effectiveContentY > flickableItem.contentHeight - flickThreshold - viewport.height + && verticalDelta < -speedThreshold) { flickableItem.flick(ignored, Math.max(-maxFlick, acceleration * verticalDelta)) } else { - flickableItem.contentY = verticalValue + flickableItem.contentY = verticalValue + flickableItem.originY } } } onHorizontalValueChanged: { if (!horizontalRecursionGuard) - flickableItem.contentX = horizontalValue + flickableItem.contentX = horizontalValue + flickableItem.originX } } |