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package com.example; | |
import android.content.Context; | |
import android.support.v7.widget.GridLayoutManager; | |
import android.support.v7.widget.RecyclerView; | |
import android.util.AttributeSet; | |
import android.view.ViewGroup; | |
public class SpanningGridLayoutManager extends GridLayoutManager { | |
public SpanningGridLayoutManager(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { | |
super(context, attrs, defStyleAttr, defStyleRes); | |
} | |
public SpanningGridLayoutManager(Context context, int spanCount) { | |
super(context, spanCount); | |
} | |
public SpanningGridLayoutManager(Context context, int spanCount, int orientation, boolean reverseLayout) { | |
super(context, spanCount, orientation, reverseLayout); | |
} | |
@Override | |
public RecyclerView.LayoutParams generateDefaultLayoutParams() { | |
return spanLayoutSize(super.generateDefaultLayoutParams()); | |
} | |
@Override | |
public RecyclerView.LayoutParams generateLayoutParams(Context c, AttributeSet attrs) { | |
return spanLayoutSize(super.generateLayoutParams(c, attrs)); | |
} | |
@Override | |
public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { | |
return spanLayoutSize(super.generateLayoutParams(lp)); | |
} | |
@Override | |
public boolean checkLayoutParams(RecyclerView.LayoutParams lp) { | |
return super.checkLayoutParams(lp); | |
} | |
private RecyclerView.LayoutParams spanLayoutSize(RecyclerView.LayoutParams layoutParams){ | |
if(getOrientation() == HORIZONTAL){ | |
layoutParams.width = (int) Math.round(getHorizontalSpace() / Math.ceil(getItemCount() / getSpanCount())); | |
} | |
else if(getOrientation() == VERTICAL){ | |
layoutParams.height = (int) Math.round(getVerticalSpace() / Math.ceil(getItemCount() / getSpanCount())); | |
} | |
return layoutParams; | |
} | |
@Override | |
public boolean canScrollVertically() { | |
return false; | |
} | |
@Override | |
public boolean canScrollHorizontally() { | |
return false; | |
} | |
private int getHorizontalSpace() { | |
return getWidth() - getPaddingRight() - getPaddingLeft(); | |
} | |
private int getVerticalSpace() { | |
return getHeight() - getPaddingBottom() - getPaddingTop(); | |
} | |
} |
First of all, thank you for this snippet. It has been of much help to me.
But I had a problem: as every item in the recyclerview has to appear on the screen, every time a change happens such as items are added or removed programmatically, all items has to be resized. Generally it works correctly but sometimes not, just only changing the item in question.
Also I had trouble when trying to change programatically the spanCount using setSpanCount.
Therefore, I made some changes to your code. I apologize I don't know how to make a new revision of this gist, and I have created a fork to upload my changes (maybe this is the right way to make a revision), what include:
- Changed from java to kotlin
- Override of checkLayoutParams method to invalidate all items sizes when a new item is added/removed.
You can find it at https://gist.github.com/vyguera/e6babe1995bff6e8694c2a14b69c595c
thanks
spanLayoutSize
should take into account any margins in thelayoutParams