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add support for vertical
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‎README.md‎

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Original file line numberDiff line numberDiff line change
@@ -6,6 +6,8 @@ Demonstrate how to custom `RecycleView#LayoutManager`
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### v1.0
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A LinearLayoutManager like LayoutManager, Horizontal and Vertical support.
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## License
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```

‎app/src/main/java/github/hellocsl/gallerylayoutmanager/MainActivity.java‎

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@@ -2,7 +2,6 @@
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import android.os.Bundle;
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import android.support.v7.app.AppCompatActivity;
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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.view.View;
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import android.view.ViewGroup;
@@ -59,8 +58,9 @@ public void onItemClick(View view, int position) {
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});
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mMainRecycle1.setAdapter(demoAdapter1);
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62-
LinearLayoutManager layoutManager2 = new LinearLayoutManager(this);
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layoutManager2.setOrientation(LinearLayoutManager.VERTICAL);
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// LinearLayoutManager layoutManager2 = new LinearLayoutManager(this);
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// layoutManager2.setOrientation(LinearLayoutManager.VERTICAL);
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GalleryLayoutManager layoutManager2 = new GalleryLayoutManager(this, GalleryLayoutManager.VERTICAL);
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mMainRecycle2.setLayoutManager(layoutManager2);
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DemoAdapter demoAdapter2 = new DemoAdapter(title) {
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@Override

‎app/src/main/java/github/hellocsl/gallerylayoutmanager/layout/GalleryLayoutManager.java‎

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Original file line numberDiff line numberDiff line change
@@ -19,14 +19,8 @@
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public class GalleryLayoutManager extends RecyclerView.LayoutManager {
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private static final String TAG = "GalleryLayoutManager";
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private final Context mContext;
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/* Consistent size applied to all child views */
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// private int mDecoratedChildWidth;
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// private int mDecoratedChildHeight;
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// private int mSelectionPosition = 0;
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private int mFirstVisiblePosition = -1;
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private int mLastVisiblePos = -1;
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// private int mSelectedIndex;
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public static final int HORIZONTAL = OrientationHelper.HORIZONTAL;
@@ -103,11 +97,103 @@ private void fillCover(RecyclerView.Recycler recycler, RecyclerView.State state,
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}
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106-
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/**
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* @param recycler
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* @param state
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* @param dy
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*/
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private void fillWithVertical(RecyclerView.Recycler recycler, RecyclerView.State state, int dy) {
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// TODO: 2016/11/19
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int topEdge = getOrientationHelper().getStartAfterPadding();
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int bottomEdge = getOrientationHelper().getEndAfterPadding();
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//1.根据滑动方向，回收越界子View
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View child;
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if (getChildCount() > 0) {
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if (dy >= 0) {
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for (int i = 0; i < getChildCount(); i++) {
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child = getChildAt(i);
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if (getDecoratedBottom(child) - dy < topEdge) {
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removeAndRecycleView(child, recycler);
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mFirstVisiblePosition++;
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} else {
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break;
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}
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}
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} else { //dy<0
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for (int i = getChildCount() - 1; i >= 0; i--) {
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child = getChildAt(i);
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if (getDecoratedTop(child) - dy > bottomEdge) {
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removeAndRecycleView(child, recycler);
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mLastVisiblePos--;
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}
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}
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}
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}
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//开始进行布局的位置
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int startPosition = mFirstVisiblePosition;
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int startOffset = -1;
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int scrapWidth, scrapHeight;
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Rect scrapRect = new Rect();
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int width = getHorizontalSpace();
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int leftOffset;
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View scrap;
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//2.根据不同滑动方向，为空余位置进行布局
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if (dy >= 0) {
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if (getChildCount() != 0) {
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View lastView = getChildAt(getChildCount() - 1);
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startPosition = getPosition(lastView) + 1; //下一个View的Position
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startOffset = getDecoratedBottom(lastView);
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}
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//考虑边界和数量
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for (int i = startPosition; i < getItemCount() && startOffset < bottomEdge; i++) {
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scrap = recycler.getViewForPosition(i);
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addView(scrap);
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measureChildWithMargins(scrap, 0, 0);
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scrapWidth = getDecoratedMeasuredWidth(scrap);
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scrapHeight = getDecoratedMeasuredHeight(scrap);
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leftOffset = (int) (getPaddingLeft() + (width - scrapWidth) / 2.0f);
156+
if (startOffset == -1 && startPosition == 0) {
157+
//第0个View，居中处理
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int top = (int) (getPaddingLeft() + (getHorizontalSpace() - scrapWidth) / 2.f);
159+
scrapRect.set(leftOffset, top, leftOffset + scrapWidth, top + scrapHeight);
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} else {
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scrapRect.set(leftOffset, startOffset, leftOffset + scrapWidth, startOffset + scrapHeight);
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}
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layoutDecorated(scrap, scrapRect.left, scrapRect.top, scrapRect.right, scrapRect.bottom);
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startOffset = scrapRect.bottom;
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((LayoutParams) scrap.getLayoutParams()).mPosition = i;
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mLastVisiblePos = i;
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getState().mItemsFrames.put(i, scrapRect);
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if (BuildConfig.DEBUG) {
169+
Log.d(TAG, "fillWithHorizontal,layout:mLastVisiblePos: " + mLastVisiblePos);
170+
}
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}
172+
} else {
173+
//dy<0
174+
if (getChildCount() > 0) {
175+
View firstView = getChildAt(0);
176+
startPosition = getPosition(firstView) - 1; //前一个View的position
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startOffset = getDecoratedTop(firstView);
178+
}
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//考虑边界和数量
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for (int i = startPosition; i >= 0 && startOffset > topEdge; i--) {
181+
scrapRect = getState().mItemsFrames.get(i);
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scrap = recycler.getViewForPosition(i);
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addView(scrap, 0);
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measureChildWithMargins(scrap, 0, 0);
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scrapWidth = scrapRect.right - scrapRect.left;
186+
scrapHeight = scrapRect.bottom - scrapRect.top;
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leftOffset = (int) (getPaddingLeft() + (width - scrapWidth) / 2.0f);
188+
layoutDecorated(scrap, leftOffset, startOffset - scrapHeight, leftOffset + scrapWidth, startOffset);
189+
startOffset -= scrapHeight;
190+
((LayoutParams) scrap.getLayoutParams()).mPosition = i;
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mFirstVisiblePosition = i;
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}
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}
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}
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/**
112198
* @param recycler
113199
* @param state
@@ -247,13 +333,9 @@ class State {
247333
*/
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int mScrollDelta;
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250-
int mInitOffset;
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252-
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public State() {
254337
mItemsFrames = new SparseArray<Rect>();
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mScrollDelta = 0;
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mInitOffset = 0;
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}
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}
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@@ -303,17 +385,27 @@ public int scrollHorizontallyBy(int dx, RecyclerView.Recycler recycler, Recycler
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@Override
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public int scrollVerticallyBy(int dy, RecyclerView.Recycler recycler, RecyclerView.State state) {
306-
if (getChildCount() == 0) {
388+
if (getChildCount() == 0 || dy == 0) {
307389
return 0;
308390
}
309-
final View topView = getChildAt(0);
310-
final View bottomView = getChildAt(getChildCount() - 1);
311-
312-
int viewSpan = getDecoratedBottom(bottomView) - getDecoratedTop(topView);
313-
if (viewSpan < getVerticalSpace()) {
314-
return 0;
391+
int delta = -dy;
392+
int parentCenter = (getOrientationHelper().getEndAfterPadding() - getOrientationHelper().getStartAfterPadding()) / 2 + getOrientationHelper().getStartAfterPadding();
393+
View child;
394+
if (dy > 0) { //手势左滑
395+
if (((LayoutParams) getChildAt(getChildCount() - 1).getLayoutParams()).mPosition == getItemCount() - 1) {
396+
child = getChildAt(getChildCount() - 1);
397+
delta = -Math.max(0, Math.min(dy, (child.getBottom() - child.getTop()) / 2 + child.getTop() - parentCenter));
398+
}
399+
} else {
400+
if (mFirstVisiblePosition == 0) {
401+
child = getChildAt(0);
402+
delta = -Math.min(0, Math.max(dy, ((child.getBottom() - child.getTop()) / 2 + child.getTop()) - parentCenter));
403+
}
315404
}
316-
return super.scrollVerticallyBy(dy, recycler, state);
405+
getState().mScrollDelta = -delta;
406+
fillCover(recycler, state, -delta);
407+
offsetChildrenVertical(delta);
408+
return -delta;
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}
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private OrientationHelper getOrientationHelper() {

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