anchor_scroll_controller

• Bugfix: sometimes can not scroll to the index for pinned header list.

• Fix issue #7: Implemented addIndexListener and removeIndexListener

Added the pinGroupTitleOffset to apply to calculate current index

• Added the pinGroupTitleOffset to apply to calculate current index

#5: Add anchorOffset parameter

• Added anchorOffset property to add some offset to each anchor

• Refactor project.
• Bugfix: fix possible infinite loop problems.

• Refactor project.
• Bugfix: fix possible infinite loop problems.

• fix: onIndexChanged will not call after AnchorScrollViewWrapper is update.
• fix issue #2: When the height of item is very large which leads to only one item is in the viewport, it will fall to infinite.
• update README.md

• Fix issue #2: When the height of item is very large which leads to only one item is in the viewport, it will fall to infinite loop.
• Bugfix: onIndexChanged will not call after AnchorScrollViewWrapper is update.

• Modify README.md

add userScroll parameter for onIndexChanged to indicate whether is scrolling by user #1

• onIndexChanged gets called regardless of how the index is changed and add a userScroll parameter for onIndexChanged to indicate whether is scrolling by user.

Support the case with already existed ScrollController

• Support the case with already existed ScrollController.
• Fix errors of the critical cases.

AnchorScrollController supports to scroll to index and listen to index changed while scrolling by user.

• Initial Open Source release.