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This is a paid asset, but now you can download Infinity Scrollview for UGUI Free.
Infinity Scrollview for UGUI
Work with Unity 4.6+ and Unity 5.0+, Unity 2017, Unity 2018 (All licenses)
Features:
+ Support Scrollview with size item from 0 to Infinity items with highest performance.
+ Support Infinity Vertical(Top To Down, Bottom To Up).
+ Support Infinity Horizontal(Left to Right, Right To Left).
+ Easy to Create Skip items in any index of scrollview (Easy to add any thing item such as Native Ads Items…).
+ Easy to use and custom like as any other UI control of UGUI.
+ Can work with all Unity platforms (PC/Mac/Console/IOS/Android/Winphone/WebGL…).
+ Working with all version of Unity 4.6 or higher, Unity 5 and above.