Java tutorial
package de.geeksfactory.opacclient.ui; import android.content.Context; import android.graphics.Canvas; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.support.v4.content.ContextCompat; import android.support.v7.widget.RecyclerView; import android.view.View; import de.geeksfactory.opacclient.R; import de.geeksfactory.opacclient.frontend.adapter.AccountAdapter; import su.j2e.rvjoiner.RvJoiner; /* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ public class AccountDividerItemDecoration extends RecyclerView.ItemDecoration { private Drawable mDividerWithInset; private Drawable mDividerWithoutInset; private RvJoiner rvJoiner; public AccountDividerItemDecoration(Context context, RvJoiner rvJoiner) { mDividerWithInset = ContextCompat.getDrawable(context, R.drawable.list_divider_inset); mDividerWithoutInset = ContextCompat.getDrawable(context, R.drawable.list_divider); this.rvJoiner = rvJoiner; } @Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) { final int left = parent.getPaddingLeft(); final int right = parent.getWidth() - parent.getPaddingRight(); final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.ViewHolder vh = parent.getChildViewHolder(child); if (!isDecorated(child, parent)) continue; if (!(vh instanceof AccountAdapter.ViewHolder)) continue; final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams(); final int top = child.getBottom() + params.bottomMargin; final Drawable drawable = (((AccountAdapter.ViewHolder) vh).isCoversHidden() ? mDividerWithoutInset : mDividerWithInset); final int bottom = top + drawable.getIntrinsicHeight(); drawable.setBounds(left, top, right, bottom); drawable.draw(c); } } @Override public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) { if (isDecorated(view, parent)) { outRect.set(0, 0, 0, mDividerWithInset.getIntrinsicHeight()); } } private boolean isDecorated(View view, RecyclerView parent) { RecyclerView.ViewHolder vh = parent.getChildViewHolder(view); if (rvJoiner != null) { if (vh instanceof AccountAdapter.ViewHolder) { RvJoiner.PositionInfo pi = rvJoiner.getPositionInfo(parent.getChildAdapterPosition(view)); return (pi != null && pi.joinable.getAdapter() instanceof AccountAdapter && pi.realPosition < pi.joinable.getAdapter().getItemCount() - 1); } return true; } else { View nextView = parent.getChildAt(parent.getChildAdapterPosition(view) + 1); if (nextView != null) { RecyclerView.ViewHolder vh2 = parent.getChildViewHolder(nextView); return vh instanceof AccountAdapter.ViewHolder && vh2 instanceof AccountAdapter.ViewHolder; } } return false; } }