Java tutorial
/* * Copyright (C) 2016 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 com.by_syk.lib.nanoiconpack.widget; import android.annotation.SuppressLint; 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.annotation.NonNull; import android.support.v4.view.ViewCompat; import android.support.v7.widget.RecyclerView; import android.view.View; import android.widget.LinearLayout; import com.by_syk.lib.nanoiconpack.R; /** * DividerItemDecoration is a {@link RecyclerView.ItemDecoration} that can be used as a divider * between items of a {@link LinearLayoutManager}. It supports both {@link #HORIZONTAL} and * {@link #VERTICAL} orientations. * * <pre> * mDividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(), * mLayoutManager.getOrientation()); * recyclerView.addItemDecoration(mDividerItemDecoration); * </pre> */ public class DividerItemDecoration extends RecyclerView.ItemDecoration { public static final int HORIZONTAL = LinearLayout.HORIZONTAL; public static final int VERTICAL = LinearLayout.VERTICAL; private static final int[] ATTRS = new int[] { android.R.attr.listDivider }; private Drawable mDivider; /** * Current orientation. Either {@link #HORIZONTAL} or {@link #VERTICAL}. */ private int mOrientation; private final Rect mBounds = new Rect(); /** * Creates a divider {@link RecyclerView.ItemDecoration} that can be used with a * {@link LinearLayoutManager}. * * @param context Current context, it will be used to access resources. * @param orientation Divider orientation. Should be {@link #HORIZONTAL} or {@link #VERTICAL}. */ public DividerItemDecoration(Context context, int orientation) { // final TypedArray a = context.obtainStyledAttributes(ATTRS); // mDivider = a.getDrawable(0); // a.recycle(); // @By_syk mDivider = context.getDrawable(R.drawable.app_list_divider); setOrientation(orientation); } /** * Sets the orientation for this divider. This should be called if * {@link RecyclerView.LayoutManager} changes orientation. * * @param orientation {@link #HORIZONTAL} or {@link #VERTICAL} */ public void setOrientation(int orientation) { if (orientation != HORIZONTAL && orientation != VERTICAL) { throw new IllegalArgumentException("Invalid orientation. It should be either HORIZONTAL or VERTICAL"); } mOrientation = orientation; } /** * Sets the {@link Drawable} for this divider. * * @param drawable Drawable that should be used as a divider. */ public void setDrawable(@NonNull Drawable drawable) { if (drawable == null) { throw new IllegalArgumentException("Drawable cannot be null."); } mDivider = drawable; } @Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) { if (parent.getLayoutManager() == null) { return; } if (mOrientation == VERTICAL) { drawVertical(c, parent); } else { drawHorizontal(c, parent); } } @SuppressLint("NewApi") private void drawVertical(Canvas canvas, RecyclerView parent) { canvas.save(); final int left; final int right; if (parent.getClipToPadding()) { left = parent.getPaddingLeft(); right = parent.getWidth() - parent.getPaddingRight(); canvas.clipRect(left, parent.getPaddingTop(), right, parent.getHeight() - parent.getPaddingBottom()); } else { left = 0; right = parent.getWidth(); } final int childCount = parent.getChildCount(); // for (int i = 0; i < childCount; i++) { // Remove the last divider // @By_syk for (int i = 0; i < childCount - 1; i++) { final View child = parent.getChildAt(i); parent.getDecoratedBoundsWithMargins(child, mBounds); final int bottom = mBounds.bottom + Math.round(ViewCompat.getTranslationY(child)); final int top = bottom - mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(canvas); } canvas.restore(); } @SuppressLint("NewApi") private void drawHorizontal(Canvas canvas, RecyclerView parent) { canvas.save(); final int top; final int bottom; if (parent.getClipToPadding()) { top = parent.getPaddingTop(); bottom = parent.getHeight() - parent.getPaddingBottom(); canvas.clipRect(parent.getPaddingLeft(), top, parent.getWidth() - parent.getPaddingRight(), bottom); } else { top = 0; bottom = parent.getHeight(); } final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); parent.getLayoutManager().getDecoratedBoundsWithMargins(child, mBounds); final int right = mBounds.right + Math.round(ViewCompat.getTranslationX(child)); final int left = right - mDivider.getIntrinsicWidth(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(canvas); } canvas.restore(); } @Override public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) { if (mOrientation == VERTICAL) { outRect.set(0, 0, 0, mDivider.getIntrinsicHeight()); } else { outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0); } } }