RecyclerView相关

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RecyclerView

  • 针对多种类型的情况，可以创建多个 ViewHolder和设置多个 type

分页加载（加载更多）

https://github.com/lyloou/lou/blob/demo/test/src/main/java/com/lyloou/test/gank/GankWelfareActivity.java

http://www.gadgetsaint.com/android/recyclerview-header-footer-pagination/#.WRwxJGh96Hs

方案一：

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mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
    @Override
    public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);

        int lastvisibleitemposition = mLayoutManager.findLastVisibleItemPosition();

        if (lastvisibleitemposition == mAdapter.getItemCount() - 1) {

            if (!loading && !isLastPage) {

                loading = true;
                fetchData((++pageCount));
                // Increment the pagecount everytime we scroll to fetch data from the next page
                // make loading = false once the data is loaded
                // call mAdapter.notifyDataSetChanged() to refresh the Adapter and Layout

            }


        }
    }
});

方案二：

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// http://www.jianshu.com/p/4feb0c16d1b5
private RecyclerView.OnScrollListener mListener = new RecyclerView.OnScrollListener() {
    @Override
    public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);
    }

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);

        LinearLayoutManager layoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();
        int lastVisibleItem = layoutManager.findLastVisibleItemPosition();
        int totalItemCount = layoutManager.getItemCount();

        if (totalItemCount < 250 && lastVisibleItem >= totalItemCount - 4) {
            // 注意：要限制请求，否则请求太多次数，导致服务器崩溃或者服务器拒绝请求（罪过，罪过）。
            if (mIsLoading) {
                Log.i(TAG, "onScrolled: " + "加载中---------");
            } else {
                Log.i(TAG, "onScrolled: " + "加载更多了=======》");
                loadSubject();
            }

        }

        Log.d(TAG, "onScrolled: lastVisibleItem=" + lastVisibleItem);
        Log.d(TAG, "onScrolled: totalItemCount=" + totalItemCount);

    }
};

加载更多调用 notifyDataSetChanged 时会白一下屏

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getDataListFromNet(++page, dataList->{
    int lastSize = mAdapter.getList().size();
    mAdapter.getList().addAll(dataList);
    // mAdapter.notifyDataSetChanged(); // 调用这个方法会白屏，可以用下面的方式解决
    mAdapter.notifyItemRangeInserted(lastSize - 1, dataList.size());
});

GridLayoutManager 均分两列的装饰器 ItemDecoration

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public class DoubleItemOffsetDecoration extends RecyclerView.ItemDecoration {
    private int offset;

    public DoubleItemOffsetDecoration(int offset) {
        this.offset = offset;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        int position = parent.getChildLayoutPosition(view);
        if (position == 0 || position == 1) {
            outRect.top = offset;
        }

        outRect.bottom = offset;
        if (position % 2 == 1) {
            outRect.left = offset / 2;
            outRect.right = offset;
        } else {
            outRect.left = offset;
            outRect.right = offset / 2;
        }
    }
}