Java tutorial
/* * 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. */ package ingvar.android.literepo.examples.widget; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.support.v4.view.ViewCompat; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.View; public class DividerItemDecoration extends RecyclerView.ItemDecoration { private static final int[] ATTRS = new int[] { android.R.attr.listDivider }; private Drawable mDivider; private int mOrientation; public DividerItemDecoration(Context context, int orientation) { final TypedArray a = context.obtainStyledAttributes(ATTRS); mDivider = a.getDrawable(0); a.recycle(); setOrientation(orientation); } public DividerItemDecoration(Context context) { this(context, LinearLayoutManager.VERTICAL); } public void setOrientation(int orientation) { if (orientation != LinearLayoutManager.HORIZONTAL && orientation != LinearLayoutManager.VERTICAL) { throw new IllegalArgumentException("invalid orientation"); } mOrientation = orientation; } @Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) { if (mOrientation == LinearLayoutManager.VERTICAL) { drawVertical(c, parent); } else { drawHorizontal(c, parent); } } @Override public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) { if (mOrientation == LinearLayoutManager.VERTICAL) { outRect.set(0, 0, 0, mDivider.getIntrinsicHeight()); } else { outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0); } } private void drawVertical(Canvas c, RecyclerView parent) { 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.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams(); final int top = child.getBottom() + params.bottomMargin + Math.round(ViewCompat.getTranslationY(child)); final int bottom = top + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } private void drawHorizontal(Canvas c, RecyclerView parent) { final int top = parent.getPaddingTop(); final int bottom = parent.getHeight() - parent.getPaddingBottom(); final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams(); final int left = child.getRight() + params.rightMargin + Math.round(ViewCompat.getTranslationX(child)); final int right = left + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } }