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OnPageChangeListener

interface OnPageChangeListener
androidx.viewpager.widget.ViewPager.OnPageChangeListener

Callback interface for responding to changing state of the selected page.

Summary

Public methods

abstract Unit

Called when the scroll state changes.

abstract Unit
onPageScrolled(position: Int, positionOffset: Float, @Px positionOffsetPixels: Int)

This method will be invoked when the current page is scrolled, either as part of a programmatically initiated smooth scroll or a user initiated touch scroll.

abstract Unit
onPageSelected(position: Int)

This method will be invoked when a new page becomes selected.

Public methods

onPageScrollStateChanged

abstract fun onPageScrollStateChanged(state: Int): Unit

Called when the scroll state changes. Useful for discovering when the user begins dragging, when the pager is automatically settling to the current page, or when it is fully stopped/idle.

Parameters
state Int: The new scroll state.

onPageScrolled

abstract fun onPageScrolled(position: Int, positionOffset: Float, @Px positionOffsetPixels: Int): Unit

This method will be invoked when the current page is scrolled, either as part of a programmatically initiated smooth scroll or a user initiated touch scroll.

Parameters
position Int: Position index of the first page currently being displayed. Page position+1 will be visible if positionOffset is nonzero.
positionOffset Int: Value from [0, 1) indicating the offset from the page at position.
positionOffsetPixels Int: Value in pixels indicating the offset from position.

onPageSelected

abstract fun onPageSelected(position: Int): Unit

This method will be invoked when a new page becomes selected. Animation is not necessarily complete.

Parameters
position Int: Position index of the new selected page.