[FLEX-34201] GridViewLayout getDataProviderItem index out of Bounds issue

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: Apache Flex 4.12.0, Apache Flex 4.12.1
• Component/s: Spark: DataGrid
• Assignee: Unassigned
• Reporter: Alexander Mazuruk
• Created: 01/Apr/14 12:37
• Updated: 13/Jun/14 10:03

Description

Class spark.components.gridClasses.GridViewLayout

Original method code:
===========================================< cut here
private function getDataProviderItem(rowIndex:int):Object

{ const dataProviderView:IList = this.dataProviderView; if ((dataProviderView == null) || (rowIndex >= dataProviderView.length) || (rowIndex < 0)) return null; return dataProviderView.getItemAt(rowIndex); }

===========================================< cut here

// This check assumes that we have "normal" dataProviderView as an IList
if ((dataProviderView == null) || (rowIndex >= dataProviderView.length) || (rowIndex < 0))
return null;

BUT, in case our dataProviderView is SubListView, normal check is not sufficient anymore. we have to check against [startIndex and count] as well like:

if ((dataProviderView is SubListView) || (rowIndex >= dataProviderView.startIndex + dataProviderView.count) || (rowIndex < dataProviderView.startIndex))
return null;

Include the case when count is equals to -1.

Better to do it inside SubListView.getItemAt() method, to avoid code duplication and checks all around SubListView usage spots.

By ignoring this we are getting kind of this traces at runtime:

RangeError: Index '11' specified is out of bounds.
at mx.collections::ListCollectionView/getItemAt()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/framework/src/mx/collections/ListCollectionView.as:512]
at spark.collections::SubListView/getItemAt()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/collections/SubListView.as:358]
at spark.components.gridClasses::GridViewLayout/getDataProviderItem()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/components/gridClasses/GridViewLayout.as:1184]
at spark.components.gridClasses::GridViewLayout/layoutItemRenderers()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/components/gridClasses/GridViewLayout.as:1564]
at spark.components.gridClasses::GridViewLayout/updateDisplayList()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/components/gridClasses/GridViewLayout.as:965]
at spark.components.supportClasses::GroupBase/updateDisplayList()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/components/supportClasses/GroupBase.as:1302]
at spark.components::Group/updateDisplayList()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/components/Group.as:1179]
at mx.core::UIComponent/validateDisplayList()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/framework/src/mx/core/UIComponent.as:9531]
at spark.components::Group/validateDisplayList()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/spark/src/spark/components/Group.as:1101]
at mx.managers::LayoutManager/validateDisplayList()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/framework/src/mx/managers/LayoutManager.as:744]
at mx.managers::LayoutManager/doPhasedInstantiation()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/framework/src/mx/managers/LayoutManager.as:827]
at mx.managers::LayoutManager/doPhasedInstantiationCallback()[/Users/justinmclean/Documents/ApacheFlex4.12.0/frameworks/projects/framework/src/mx/managers/LayoutManager.as:1188]