Skip to content

Instantly share code, notes, and snippets.

@akmalxxx
Created October 29, 2014 12:10
Show Gist options
  • Save akmalxxx/233abbae200b5e87297b to your computer and use it in GitHub Desktop.
Save akmalxxx/233abbae200b5e87297b to your computer and use it in GitHub Desktop.
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.LinearLayoutManager;
import android.view.View;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.graphics.Canvas;
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private Drawable mDivider;
public DividerItemDecoration(Context context, AttributeSet attrs) {
final TypedArray a = context.obtainStyledAttributes(attrs, new int [] { android.R.attr.listDivider });
mDivider = a.getDrawable(0);
a.recycle();
}
public DividerItemDecoration(Drawable divider) { mDivider = divider; }
@Override
public void getItemOffsets (Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
if (mDivider == null) return;
if (parent.getChildPosition(view) < 1) return;
if (getOrientation(parent) == LinearLayoutManager.VERTICAL) outRect.top = mDivider.getIntrinsicHeight();
else outRect.left = mDivider.getIntrinsicWidth();
}
@Override
public void onDrawOver(Canvas c, RecyclerView parent) {
if (mDivider == null) { super.onDrawOver(c, parent); return; }
if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
final int left = parent.getPaddingLeft();
final int right = parent.getWidth() - parent.getPaddingRight();
final int childCount = parent.getChildCount();
for (int i=1; i < childCount; i++) {
final View child = parent.getChildAt(i);
final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
final int size = mDivider.getIntrinsicHeight();
final int top = child.getTop() - params.topMargin;
final int bottom = top + size;
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
} else { //horizontal
final int top = parent.getPaddingTop();
final int bottom = parent.getHeight() - parent.getPaddingBottom();
final int childCount = parent.getChildCount();
for (int i=1; i < childCount; i++) {
final View child = parent.getChildAt(i);
final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
final int size = mDivider.getIntrinsicWidth();
final int left = child.getLeft() - params.leftMargin;
final int right = left + size;
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
}
private int getOrientation(RecyclerView parent) {
if (parent.getLayoutManager() instanceof LinearLayoutManager) {
LinearLayoutManager layoutManager = (LinearLayoutManager) parent.getLayoutManager();
return layoutManager.getOrientation();
} else throw new IllegalStateException("DividerItemDecoration can only be used with a LinearLayoutManager.");
}
}
@pnickv
Copy link

pnickv commented Nov 13, 2014

something like
...
mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view);
mRecyclerView.addItemDecoration(new DividerItemDecoration(getResources().getDrawable(R.drawable.abc_list_divider_mtrl_alpha)));

@cbedoy
Copy link

cbedoy commented Nov 21, 2014

is it most easy if declare a xml with margin top and margin bottom?

Copy link

ghost commented Dec 2, 2014

This si also deprecated now, onDrawOver should now also take in RecyclerView.State

@lapastillaroja
Copy link

@fatfingers
Thanks for sharing this git.
I forked and modified your DividerItemDecoration. I hope can be useful to somebody.

https://gist.github.com/lapastillaroja/858caf1a82791b6c1a36

@franciscossb
Copy link

Great work, but how can I set the divider height?

Thank you

@svenoaks
Copy link

Why do we now need 75 lines of code to draw a list divider?

@aNinjaMonk
Copy link

Because GOOGLE assumes android developers are not humans ...... but super humans... who for example if asked for time will first invent a clock and then a time machine to go back into the moment you asked for time and then tell you the time... developing for iOS is much more human...

@atabouraya
Copy link

@cbedoy you still have a problem with the first and the last items, usually you don't need margin top for the first item and margin bottom for the last one

@MrThiago
Copy link

Hi, I tried it. but I get an error, Call require API level 21

mListView.addItemDecoration(
new DividerItemDecoration(getActivity().getDrawable(R.drawable.ic_launcher), true, true));

@aricneto
Copy link

@MrThiago, getDrawable(int, theme) is for API 21+ only. Use

ContextCompat.getDrawable(getApplicationContext(), R.drawable.ic_launcher)

@mudao
Copy link

mudao commented Aug 9, 2015

this only for LinearLayoutManager ? How can I draw dividers for StaggeredGridManager or GridLayoutManager?

@pratikbutani
Copy link

getChildPosition and onDrawOver deprecated. What should i do?

@ChaosLeung
Copy link

@pratikbutani
use getChildAdapterPosition or getChildLayoutPosition instead getChildPosition

use

public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state)

instead

public void onDrawOver(Canvas c, RecyclerView parent)

@seyoung-hyun
Copy link

@fatfingers
Hi, I'm Seyoung.
I want to use your code in my commercial app.
But I can'f find any terms and conditions for use, reproduction, and distribution.
I wonder if I can use the code for commercial distribution or not.
Please let me know how I can use the code for commercial distribution.
Thanks.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment