Android Recyclerview 网格布局分割线

来源:互联网 时间:2018-03-03

1上一篇仿微信图片选择器的时候分割线出了点bug,其实是我把一块关键代码删掉了,不过无关紧要,这次单独写一篇

2csdn上hongyang大神已经写过了,但是按照他写的方法我自己试了一下网格布局的有点问题,具体是什么问题已经记不清了(没有质疑大神代码的意思,貌似是他的代码有一个方法过期了),我这个是自己亲测没问题的

3步骤,新建一个DiciderGridItemDecoration

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.IntDef;import android.support.v4.view.ViewCompat;import android.support.v7.widget.GridLayoutManager;import android.support.v7.widget.RecyclerView;import android.support.v7.widget.StaggeredGridLayoutManager;import android.util.SparseArray;import android.util.SparseIntArray;import android.view.View;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;/** * Created by MAC on 2018/2/5. */public class DividerGridItemDecoration extends RecyclerView.ItemDecoration { private static final int[] ATTRS = new int[]{android.R.attr.listDivider}; //这个就是设置样式的地方(颜色,宽度等等) public static final int GRID_DIVIDER_HORIZONTAL = GridLayoutManager.HORIZONTAL; public static final int GRID_DIVIDER_VERTICAL = GridLayoutManager.VERTICAL; private final SparseIntArray mHorizontalDividerOffsets = new SparseIntArray(); private final SparseIntArray mVerticalDividerOffsets = new SparseIntArray(); private final SparseArray<DrawableCreator> mTypeDrawableFactories = new SparseArray<>(); @IntDef({ GRID_DIVIDER_HORIZONTAL, GRID_DIVIDER_VERTICAL }) @Retention(RetentionPolicy.SOURCE) private @interface Orientation { } @Orientation private int mOrientation; private Drawable mHorizontalDivider; private Drawable mVerticalDivider; public DividerGridItemDecoration(Context context, @Orientation int orientation) { resolveDivider(context); setOrientation(orientation); } private void resolveDivider(Context context) { final TypedArray a = context.obtainStyledAttributes(ATTRS); mVerticalDivider = mHorizontalDivider = a.getDrawable(0); a.recycle(); } public void setOrientation(int orientation) { this.mOrientation = orientation; } public void setVerticalDivider(Drawable verticalDivider) { this.mVerticalDivider = verticalDivider; } public void setHorizontalDivider(Drawable horizontalDivider) { this.mHorizontalDivider = horizontalDivider; } @Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) { drawHorizontalDividers(c, parent); drawVerticalDividers(c, parent); } @Override public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) { final int spanCount = getSpanCount(parent); final int childCount = parent.getAdapter().getItemCount(); final int adapterPosition = parent.getChildAdapterPosition(view); if (mHorizontalDividerOffsets.indexOfKey(adapterPosition) < 0) { mHorizontalDividerOffsets.put(adapterPosition, getHorizontalDivider(parent, adapterPosition).getIntrinsicHeight()); } if (mVerticalDividerOffsets.indexOfKey(adapterPosition) < 0) { mVerticalDividerOffsets.put(adapterPosition, getVerticalDivider(parent, adapterPosition).getIntrinsicHeight()); } outRect.set(0, 0, mHorizontalDividerOffsets.get(adapterPosition), mVerticalDividerOffsets.get(adapterPosition)); if (isLastRow(adapterPosition, spanCount, childCount)) { outRect.bottom = 0; } if (isLastColumn(adapterPosition, spanCount, childCount)) { outRect.right = 0; } } private boolean isLastColumn(int position, int spanCount, int childCount) { if (mOrientation == GRID_DIVIDER_VERTICAL) { return (position + 1) % spanCount == 0; } else { int lastColumnCount = childCount % spanCount; lastColumnCount = lastColumnCount == 0 ? spanCount : lastColumnCount; return position >= childCount - lastColumnCount; } } private boolean isLastRow(int position, int spanCount, int childCount) { if (mOrientation == GRID_DIVIDER_VERTICAL) { int lastColumnCount = childCount % spanCount; lastColumnCount = lastColumnCount == 0 ? spanCount : lastColumnCount; return position >= childCount - lastColumnCount; } else { return (position + 1) % spanCount == 0; } } private int getSpanCount(RecyclerView parent) { RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { return ((GridLayoutManager) layoutManager).getSpanCount(); } else if (layoutManager instanceof StaggeredGridLayoutManager) { return ((StaggeredGridLayoutManager) layoutManager).getSpanCount(); } else { throw new UnsupportedOperationException("the GridDividerItemDecoration can only be used in " + "the RecyclerView which use a GridLayoutManager or StaggeredGridLayoutManager"); } } public void drawVerticalDividers(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 Drawable divider = getVerticalDivider(parent, params.getViewAdapterPosition()); final int top = child.getBottom() + params.bottomMargin + Math.round(ViewCompat.getTranslationY(child)); final int bottom = top + divider.getIntrinsicHeight(); mVerticalDividerOffsets.put(params.getViewAdapterPosition(), divider.getIntrinsicHeight()); divider.setBounds(left, top, right, bottom); divider.draw(c); } } public void drawHorizontalDividers(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 Drawable divider = getHorizontalDivider(parent, params.getViewAdapterPosition()); final int left = child.getRight() + params.rightMargin + Math.round(ViewCompat.getTranslationX(child)); final int right = left + divider.getIntrinsicHeight(); mHorizontalDividerOffsets.put(params.getViewAdapterPosition(), divider.getIntrinsicHeight()); divider.setBounds(left, top, right, bottom); divider.draw(c); } } private Drawable getVerticalDivider(RecyclerView parent, int adapterPosition) { RecyclerView.Adapter adapter = parent.getAdapter(); int itemType = adapter.getItemViewType(adapterPosition); DrawableCreator drawableCreator = mTypeDrawableFactories.get(itemType); if (drawableCreator != null) { return drawableCreator.createVertical(parent, adapterPosition); } return mVerticalDivider; } private Drawable getHorizontalDivider(RecyclerView parent, int adapterPosition) { RecyclerView.Adapter adapter = parent.getAdapter(); int itemType = adapter.getItemViewType(adapterPosition); DrawableCreator drawableCreator = mTypeDrawableFactories.get(itemType); if (drawableCreator != null) { return drawableCreator.createHorizontal(parent, adapterPosition); } return mHorizontalDivider; } public void registerTypeDrawable(int itemType, DrawableCreator drawableCreator) { mTypeDrawableFactories.put(itemType, drawableCreator); } public interface DrawableCreator { Drawable createVertical(RecyclerView parent, int adapterPosition); Drawable createHorizontal(RecyclerView parent, int adapterPosition); }}

4下一步 在drawable文件夹下新建分割线样式 ,divider_bg.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle" > <gradient //说来惭愧,这个是设置渐变色的,为了省事我直接把三个色改成相同颜色(正常写corners,solid,stroke这些应该也是可以的我自己没试) android:centerColor="#F5F6F6" android:endColor="#F5F6F6" android:startColor="#F5F6F6" android:type="linear" /> <size android:height="4dp"/></shape>

5下一步 在manifests 的 application里找到them,点击进入并修改

<style name="PlayerTheme" parent="Theme.AppCompat.NoActionBar"> <item name="android:windowAnimationStyle">@style/PlayerAnimation</item> <item name="android:listDivider">@drawable/divider_bg</item>//主要就是加上这句话,其他的代码跟分割线无关(具体的可以看hongyang大神的博客) </style>

6使用

binding.recyclerview.setLayoutManager(new GridLayoutManager(context, 2));binding.recyclerview.addItemDecoration(new DividerGridItemDecoration(context, DividerGridItemDecoration.GRID_DIVIDER_VERTICAL));//最后这个参数应该就是设置分割线的方向的,如果是不变色的分割线怎么设置无所谓,变色的线就自己决定方向吧

7总结一下,其实非常的简单,把DividerGridItemDecoration复制一下,写一个样式,把样式添加到them里,然后一行代码调用

相关阅读:
Top