网格布局的RecyclerView高度随Item自适应

摘要: 网格布局的RecyclerView高度随Item自适应

表格样式的RecyclerView高度随Item自适应 的解决办法就是自己去重写布局管理器GridLayoutManager。

package com.art.artcircle.widget;

import android.content.Context;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.view.ViewGroup;
public class WrapHeightGridLayoutManager extends GridLayoutManager {

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

public WrapHeightGridLayoutManager(Context context, int spanCount) {
super(context, spanCount);
this.mChildPerLines = spanCount;
}

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

final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);
int height = 0;
for (int i = 0; i < getItemCount(); ) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);
height = height + mMeasuredDimension[1];
i = i + mChildPerLines;
}

// If child view is more than screen size, there is no need to make it wrap content. We can use original onMeasure() so we can scroll view.
if (height >heightSize) {
switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
setMeasuredDimension(widthSize, height);
} else {
super.onMeasure(recycler, state, widthSpec, heightSpec);
}
}

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

View view = recycler.getViewForPosition(position);

// For adding Item Decor Insets to view
super.measureChildWithMargins(view, 0, 0);
if (view != null) {
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
getPaddingLeft() + getPaddingRight() + getDecoratedLeft(view) + getDecoratedRight(view), p.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
getPaddingTop() + getPaddingBottom() + getPaddingBottom() + getDecoratedBottom(view), p.height);
view.measure(childWidthSpec, childHeightSpec);

// Get decorated measurements
measuredDimension[0] = getDecoratedMeasuredWidth(view) + p.leftMargin + p.rightMargin;
measuredDimension[1] = getDecoratedMeasuredHeight(view) + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
}
}
在Activity中这样使用：

WrapHeightGridLayoutManager gm = new WrapHeightGridLayoutManager(mContext, Constant.RECYCLERVIEW_SIZE_GRIDLAYOUT_FIVE);
mPhotosRcv.setLayoutManager(gm);

这样就完美实现你想要的RecyclerView高度随Item自适应效果了。