Android RecyclerView和ScrollView嵌套使用

我们的recyclerView有多个layoutmanager，通过重写layoutmanager的方法就可以让recyclerView和ScrollView嵌套了。但是请注意，如果recyclerView很长那么强烈不建议去做嵌套，因为这样recyclerView会在展示的时候立刻展示所有内容，效率极低。

本文的两部分代码来自一个博主的博客，另一个是我自己写的，正好可以完全适用于现有的layoutmanager。大家需要的话可以试试，应该问题不大。

原博主的demo：https://github.com/Frank-Zhu/AndroidRecyclerViewDemo

1.LinearLayoutManager和ScrollView嵌套

package com.frankzhu.recyclerviewdemo;

import android.content.Context;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;

/**
* Author:    ZhuWenWu
* Version    V1.0
* Date:      2015/2/26  14:15.
* Description:
* Modification  History:
* Date             Author                Version            Description
* -----------------------------------------------------------------------------------
* 2015/2/26        ZhuWenWu            1.0                    1.0
* Why & What is modified:
*/
public class FullyLinearLayoutManager extends LinearLayoutManager {

private static final String TAG = FullyLinearLayoutManager.class.getSimpleName();

public FullyLinearLayoutManager(Context context) {
super(context);
}

public FullyLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
super(context, orientation, reverseLayout);
}

private int[] mMeasuredDimension = new int[2];

@Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state,
int widthSpec, int heightSpec) {

final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);

Log.i(TAG, "onMeasure called. \nwidthMode " + widthMode
+ " \nheightMode " + heightSpec
+ " \nwidthSize " + widthSize
+ " \nheightSize " + heightSize
+ " \ngetItemCount() " + getItemCount());

int width = 0;
int height = 0;
for (int i = 0; i < getItemCount(); i++) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);

if (getOrientation() == HORIZONTAL) {
width = width + mMeasuredDimension[0];
if (i == 0) {
height = mMeasuredDimension[1];
}
} else {
height = height + mMeasuredDimension[1];
if (i == 0) {
width = mMeasuredDimension[0];
}
}
}
switch (widthMode) {
case View.MeasureSpec.EXACTLY:
width = widthSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}

switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}

setMeasuredDimension(width, height);
}

private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {
try {
View view = recycler.getViewForPosition(0);//fix 动态添加时报IndexOutOfBoundsException

if (view != null) {
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();

int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
getPaddingLeft() + getPaddingRight(), p.width);

int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
getPaddingTop() + getPaddingBottom(), p.height);

view.measure(childWidthSpec, childHeightSpec);
measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
}
}
}

2.GridLayoutManager和ScrollView进行嵌套

package com.frankzhu.recyclerviewdemo;

import android.content.Context;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.view.ViewGroup;

/**
* Author:    ZhuWenWu
* Version    V1.0
* Date:      2015/2/26  14:14.
* Description:
* Modification  History:
* Date             Author                Version            Description
* -----------------------------------------------------------------------------------
* 2015/2/26        ZhuWenWu            1.0                    1.0
* Why & What is modified:
*/
public class FullyGridLayoutManager extends GridLayoutManager {
public FullyGridLayoutManager(Context context, int spanCount) {
super(context, spanCount);
}

public FullyGridLayoutManager(Context context, int spanCount, int orientation, boolean reverseLayout) {
super(context, spanCount, orientation, reverseLayout);
}

private int[] mMeasuredDimension = new int[2];

@Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) {
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);

int width = 0;
int height = 0;
int count = getItemCount();
int span = getSpanCount();
for (int i = 0; i < count; i++) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);

if (getOrientation() == HORIZONTAL) {
if (i % span == 0) {
width = width + mMeasuredDimension[0];
}
if (i == 0) {
height = mMeasuredDimension[1];
}
} else {
if (i % span == 0) {
height = height + mMeasuredDimension[1];
}
if (i == 0) {
width = mMeasuredDimension[0];
}
}
}

switch (widthMode) {
case View.MeasureSpec.EXACTLY:
width = widthSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}

switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}

setMeasuredDimension(width, height);
}

private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {
if (position < getItemCount()) {
try {
View view = recycler.getViewForPosition(0);//fix 动态添加时报IndexOutOfBoundsException
if (view != null) {
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
getPaddingLeft() + getPaddingRight(), p.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
getPaddingTop() + getPaddingBottom(), p.height);
view.measure(childWidthSpec, childHeightSpec);
measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}

[b]3.StaggeredGridLayoutManager和ScrollView进行嵌套[/b]

package com.kale.waterfalldemo.extra.RecyclerView;

import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.view.View;
import android.view.ViewGroup;

/**
* @author Jack Tony
* @brief 不规则排列（类似于瀑布流）的布局管理器
* @date 2015/4/6
*/
public class ExStaggeredGridLayoutManager extends StaggeredGridLayoutManager {

public ExStaggeredGridLayoutManager(int spanCount, int orientation) {
super(spanCount, orientation);
}

// 尺寸的数组，[0]是宽，[1]是高
private int[] measuredDimension = new int[2];

// 用来比较同行/列那个item罪宽/高
private int[] dimension;

@Override

public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) {
// 宽的mode+size
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
// 高的mode + size
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);

// 自身宽高的初始值
int width = 0;
int height = 0;
// item的数目
int count = getItemCount();
// item的列数
int span = getSpanCount();
// 根据行数或列数来创建数组
dimension = new int[span];

for (int i = 0; i < count; i++) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED), measuredDimension);

// 如果是竖直的列表，计算item的高，否则计算宽度
//Log.d("LISTENER", "position " + i + " height = " + measuredDimension[1]);
if (getOrientation() == VERTICAL) {
dimension[findMinIndex(dimension)] += measuredDimension[1];
} else {
dimension[findMinIndex(dimension)] += measuredDimension[0];
}
}
if (getOrientation() == VERTICAL) {
height = findMax(dimension);
} else {
width = findMax(dimension);
}

switch (widthMode) {
// 当控件宽是match_parent时，宽度就是父控件的宽度
case View.MeasureSpec.EXACTLY:
width = widthSize;
break;
case View.MeasureSpec.AT_MOST:
break;
case View.MeasureSpec.UNSPECIFIED:
break;
}
switch (heightMode) {
// 当控件高是match_parent时，高度就是父控件的高度
case View.MeasureSpec.EXACTLY:
height = heightSize;
break;
case View.MeasureSpec.AT_MOST:
break;
case View.MeasureSpec.UNSPECIFIED:
break;
}
// 设置测量尺寸
setMeasuredDimension(width, height);
}

private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {

// 挨个遍历所有item
if (position < getItemCount()) {
try {
View view = recycler.getViewForPosition(position);//fix 动态添加时报IndexOutOfBoundsException

if (view != null) {
RecyclerView.LayoutParams lp = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, getPaddingLeft() + getPaddingRight(), lp.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, getPaddingTop() + getPaddingBottom(), lp.height);
// 子view进行测量，然后可以通过getMeasuredWidth()获得测量的宽，高类似
view.measure(childWidthSpec, childHeightSpec);
// 将item的宽高放入数组中
measuredDimension[0] = view.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;
measuredDimension[1] = view.getMeasuredHeight() + lp.topMargin + lp.bottomMargin;
recycler.recycleView(view);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}

private int findMax(int[] array) {
int max = array[0];
for (int value : array) {
if (value > max) {
max = value;
}
}
return max;
}

/**
* 得到最数组中最小元素的下标
*
* @param array
* @return
*/
private int findMinIndex(int[] array) {
int index = 0;
int min = array[0];
for (int i = 0; i < array.length; i++) {
if (array[i] < min) {
min = array[i];
index = i;
}
}
return index;
}

}