Make pager a completely separate class for easier reuse

This commit is contained in:
Ensar Sarajčić 2023-08-23 12:56:36 +02:00
parent 53efffde51
commit 59975c77f4
1 changed files with 285 additions and 268 deletions

View File

@ -11,6 +11,7 @@ import android.content.Context
import android.graphics.*
import android.graphics.drawable.BitmapDrawable
import android.os.Bundle
import android.os.Handler
import android.text.Layout
import android.text.StaticLayout
import android.text.TextPaint
@ -67,7 +68,14 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
private var redrawWidgets = false
private var iconSize = 0
private val pager = Pager()
private val pager = AnimatedGridPager(
getMaxPage = ::getMaxPage,
redrawGrid = ::redrawGrid,
getWidth = { width },
getHandler = { handler },
getNextPageBound = { right - sideMargins.right - cellWidth / 2 },
getPrevPageBound = { left + sideMargins.left + cellWidth / 2 }
)
// apply fake margins at the home screen. Real ones would cause the icons be cut at dragging at screen sides
var sideMargins = Rect()
@ -203,7 +211,7 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
return
}
if (draggedItemCurrentCoords.first == -1 && draggedItemCurrentCoords.second == -1 && draggedItem != null) {
if (draggedItemCurrentCoords.first == -1 && draggedItemCurrentCoords.second == -1) {
if (draggedItem!!.type == ITEM_TYPE_WIDGET) {
val draggedWidgetView = widgetViews.firstOrNull { it.tag == draggedItem?.widgetId }
if (draggedWidgetView != null) {
@ -965,14 +973,40 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
fun setSwipeMovement(diffX: Float) {
if (draggedItem != null) {
pager.setSwipeMovement(diffX)
}
}
fun finalizeSwipe() {
pager.finalizeSwipe()
}
}
/**
* Helper class responsible for managing current page and providing utilities for animating page changes,
* as well as partial dragigng between pages
*/
private class AnimatedGridPager(
private val getMaxPage: () -> Int,
private val redrawGrid: () -> Unit,
private val getWidth: () -> Int,
private val getHandler: () -> Handler,
private val getNextPageBound: () -> Int,
private val getPrevPageBound: () -> Int,
) {
companion object {
private const val PAGE_CHANGE_HOLD_THRESHOLD = 500L
private const val PAGE_INDICATORS_FADE_DELAY = PAGE_CHANGE_HOLD_THRESHOLD + 300L
private enum class PageChangeArea {
LEFT,
MIDDLE,
RIGHT
}
}
private inner class Pager {
private var lastPage = 0
private var currentPage = 0
private var pageChangeLastArea = PageChangeArea.MIDDLE
@ -988,7 +1022,7 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
fun isItemOnLastPage(item: HomeScreenGridItem) = item.page == lastPage
fun getPageCount() = max(getMaxPage(), pager.currentPage) + 1
fun getPageCount() = max(getMaxPage(), currentPage) + 1
fun isOutsideOfPageRange() = currentPage > getMaxPage()
@ -998,12 +1032,12 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
fun isSwiped() = abs(pageChangeSwipedPercentage) > 0f
fun isAnimatingPageChange() = pager.pageChangeAnimLeftPercentage > 0f
fun isAnimatingPageChange() = pageChangeAnimLeftPercentage > 0f
fun shouldDisplayPageChangeIndicator() = isSwiped() || isAnimatingPageChange() || pageChangeIndicatorsAlpha > 0f
fun getPageChangeIndicatorsAlpha() = if (pageChangeIndicatorsAlpha != 0f) {
(pager.pageChangeIndicatorsAlpha * 255.0f).toInt()
(pageChangeIndicatorsAlpha * 255.0f).toInt()
} else {
255
}
@ -1053,12 +1087,12 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
}
fun setSwipeMovement(diffX: Float) {
if (!pageChangeEnabled || draggedItem != null) {
if (!pageChangeEnabled) {
return
}
if (currentPage < getMaxPage() && diffX > 0f || currentPage > 0 && diffX < 0f) {
pageChangeSwipedPercentage = (-diffX / width.toFloat()).coerceIn(-1f, 1f)
pageChangeSwipedPercentage = (-diffX / getWidth().toFloat()).coerceIn(-1f, 1f)
redrawGrid()
}
}
@ -1089,11 +1123,11 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
fun handleItemMovement(x: Int, y: Int) {
showIndicators()
if (x > right - sideMargins.right - cellWidth / 2) {
if (x > getNextPageBound()) {
doWithPageChangeDelay(PageChangeArea.RIGHT) {
nextOrAdditionalPage()
}
} else if (x < left + sideMargins.left + cellWidth / 2) {
} else if (x < getPrevPageBound()) {
doWithPageChangeDelay(PageChangeArea.LEFT) {
prevPage()
}
@ -1162,23 +1196,23 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
private fun showIndicators() {
pageChangeIndicatorsAlpha = 1f
removeCallbacks(startFadingIndicators)
getHandler().removeCallbacks(startFadingIndicators)
}
private fun clearPageChangeFlags() {
pageChangeLastArea = PageChangeArea.MIDDLE
pageChangeLastAreaEntryTime = 0
removeCallbacks(checkAndExecuteDelayedPageChange)
getHandler().removeCallbacks(checkAndExecuteDelayedPageChange)
}
private fun schedulePageChange() {
pageChangeLastAreaEntryTime = System.currentTimeMillis()
postDelayed(checkAndExecuteDelayedPageChange, PAGE_CHANGE_HOLD_THRESHOLD)
getHandler().postDelayed(checkAndExecuteDelayedPageChange, PAGE_CHANGE_HOLD_THRESHOLD)
}
private fun scheduleIndicatorsFade() {
pageChangeIndicatorsAlpha = 1f
postDelayed(startFadingIndicators, PAGE_INDICATORS_FADE_DELAY)
getHandler().postDelayed(startFadingIndicators, PAGE_INDICATORS_FADE_DELAY)
}
private fun doWithPageChangeDelay(needed: PageChangeArea, pageChangeFunction: () -> Boolean) {
@ -1208,7 +1242,7 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
pageChangeIndicatorsAlpha = 0f
val startingAt = 1 - abs(pageChangeSwipedPercentage)
pageChangeSwipedPercentage = 0f
removeCallbacks(startFadingIndicators)
getHandler().removeCallbacks(startFadingIndicators)
if (redraw) {
redrawGrid()
}
@ -1224,11 +1258,7 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
pageChangeAnimLeftPercentage = 0f
pageChangeEnabled = true
lastPage = currentPage
if (draggedItem != null) {
schedulePageChange()
} else {
clearPageChangeFlags()
}
scheduleIndicatorsFade()
redrawGrid()
}
@ -1236,17 +1266,4 @@ class HomeScreenGrid(context: Context, attrs: AttributeSet, defStyle: Int) : Rel
start()
}
}
}
companion object {
private const val PAGE_CHANGE_HOLD_THRESHOLD = 500L
private const val PAGE_INDICATORS_FADE_DELAY = PAGE_CHANGE_HOLD_THRESHOLD + 300L
private enum class PageChangeArea {
LEFT,
MIDDLE,
RIGHT
}
}
}