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@@ -0,0 +1,85 @@
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+/*
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+ * COPYRIGHT (c) 2018 All rights reserved by HANWHA LIFE.
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+ */
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+package kr.co.zumo.app.lifeplus.view.screen.category;
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+
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+/**
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+ * EndlessScrollListener
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+ * <pre>
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+ * </pre>
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+ *
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+ * @author 민효동
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+ * @version 1.0
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+ * @history 민효동 [2019-03-26] [최초 작성]
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+ * @since 2019-03-26
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+ */
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+
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+import android.support.v7.widget.GridLayoutManager;
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+import android.support.v7.widget.LinearLayoutManager;
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+import android.support.v7.widget.RecyclerView;
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+import android.support.v7.widget.StaggeredGridLayoutManager;
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+
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+public abstract class EndlessRecyclerViewScrollListener extends RecyclerView.OnScrollListener {
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+ // The minimum amount of items to have below your current scroll position
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+ // before loading more.
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+ private int visibleThreshold = 1;
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+
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+ private RecyclerView.LayoutManager mLayoutManager;
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+
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+ public EndlessRecyclerViewScrollListener(RecyclerView.LayoutManager layoutManager) {
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+ this.mLayoutManager = layoutManager;
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+
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+ if (mLayoutManager instanceof StaggeredGridLayoutManager) {
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+ visibleThreshold = visibleThreshold * ((StaggeredGridLayoutManager) mLayoutManager).getSpanCount();
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+ }
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+ else if (mLayoutManager instanceof GridLayoutManager) {
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+ visibleThreshold = visibleThreshold * ((GridLayoutManager) mLayoutManager).getSpanCount();
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+ }
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+ }
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+
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+ private int getLastVisibleItem(int[] lastVisibleItemPositions) {
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+ int maxSize = 0;
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+ for (int i = 0; i < lastVisibleItemPositions.length; i++) {
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+ if (i == 0) {
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+ maxSize = lastVisibleItemPositions[i];
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+ }
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+ else if (lastVisibleItemPositions[i] > maxSize) {
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+ maxSize = lastVisibleItemPositions[i];
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+ }
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+ }
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+ return maxSize;
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+ }
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+
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+ // This happens many times a second during a scroll, so be wary of the code you place here.
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+ // We are given a few useful parameters to help us work out if we need to load some more data,
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+ // but first we check if we are waiting for the previous load to finish.
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+ @Override
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+ public void onScrolled(RecyclerView view, int dx, int dy) {
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+ int lastVisibleItemPosition = 0;
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+ int totalItemCount = mLayoutManager.getItemCount();
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+
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+ if (mLayoutManager instanceof StaggeredGridLayoutManager) {
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+ int[] lastVisibleItemPositions = ((StaggeredGridLayoutManager) mLayoutManager).findLastVisibleItemPositions(null);
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+ // get maximum element within the list
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+ lastVisibleItemPosition = getLastVisibleItem(lastVisibleItemPositions);
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+ }
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+ else if (mLayoutManager instanceof GridLayoutManager) {
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+ lastVisibleItemPosition = ((GridLayoutManager) mLayoutManager).findLastVisibleItemPosition();
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+ }
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+ else if (mLayoutManager instanceof LinearLayoutManager) {
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+ lastVisibleItemPosition = ((LinearLayoutManager) mLayoutManager).findLastVisibleItemPosition();
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+ }
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+
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+ // If it isn’t currently loading, we check to see if we have breached
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+ // the visibleThreshold and need to reload more data.
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+ // If we do need to reload some more data, we execute onScrollEnd to fetch the data.
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+ // threshold should reflect how many total columns there are too
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+ if ((lastVisibleItemPosition + visibleThreshold) > totalItemCount) {
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+ onScrollEnd();
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+ }
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+ }
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+
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+ // Defines the process for actually loading more data based on page
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+ public abstract void onScrollEnd();
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+
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+}
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hyodong.min