Add DividerItemDecoration both sides of recyclerView - android

I'm trying make GUI for an app in Android I'm novice in that.
First I make a horizontal recyclerView, add DividerItemDecoration with a custom drawable and and setup LinearSnapHelper for always snap to center.
It works, but the left side is next to side of the screen because dividerItemDecorator only put the line between elements.
Exists any way to put divider at start of the recycler, I have tried put some padding or margin but when I slide it "cuts" before reach the end of the screen
Sorry in advance for the English
My code is
MainActivity
#BindView(R.id.rvRecentNews)
RecyclerView rvRecentNews;
private ArrayList<String> horizontalList;
private HorizontalAdapter horizontalAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
ButterKnife.bind(this);
horizontalList=new ArrayList<>();
horizontalList.add("horizontal 1");
horizontalList.add("horizontal 2");
horizontalList.add("horizontal 3");
horizontalList.add("horizontal 4");
horizontalList.add("horizontal 5");
horizontalList.add("horizontal 6");
horizontalList.add("horizontal 7");
horizontalList.add("horizontal 8");
horizontalList.add("horizontal 9");
horizontalList.add("horizontal 10");
horizontalAdapter=new HorizontalAdapter(horizontalList);
LinearLayoutManager horizontalLayoutManagaer
= new LinearLayoutManager(MainActivity.this, LinearLayoutManager.HORIZONTAL, false);
rvRecentNews.setLayoutManager(horizontalLayoutManagaer);
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(rvRecentNews.getContext(),
horizontalLayoutManagaer.getOrientation());
dividerItemDecoration.setDrawable(getApplicationContext().getResources().getDrawable(R.drawable.line_divider));
rvRecentNews.addItemDecoration(dividerItemDecoration);
SnapHelper helper = new LinearSnapHelper();
helper.attachToRecyclerView(rvRecentNews);
rvRecentNews.setAdapter(horizontalAdapter);
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:orientation="vertical"
tools:context="com.sgd.pawfriends.MainActivity"
tools:showIn="#layout/app_bar_main">
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:layout_marginTop="8dp"
android:id="#+id/rvRecentNews"
android:layout_width="match_parent"
android:layout_height="200dp"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</LinearLayout>
</ScrollView>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="salir"
android:onClick="logout"
/>
</LinearLayout>
Thanks in advance

Try this:
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipToPadding="false"
android:paddingLeft="10dp"/>
clipToPadding="false" means, only clip when scroll reaches to end/start point.

I found in this page many options for implement custom ItemDecoration
https://www.bignerdranch.com/blog/a-view-divided-adding-dividers-to-your-recyclerview-with-itemdecoration/
and i only change
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(rvRecentNews.getContext(),
horizontalLayoutManagaer.getOrientation());
dividerItemDecoration.setDrawable(ContextCompat.getDrawable(this,R.drawable.line_divider));
rvRecentNews.addItemDecoration(dividerItemDecoration);
for this
rvRecentNews.addItemDecoration(new StartOffsetItemDecoration(ContextCompat.getDrawable(this,R.drawable.line_divider)));
class StartOffsetItemDecoration
public class StartOffsetItemDecoration extends RecyclerView.ItemDecoration {
private int mOffsetPx;
private Drawable mOffsetDrawable;
private int mOrientation;
public StartOffsetItemDecoration(int offsetPx) {
mOffsetPx = offsetPx;
}
public StartOffsetItemDecoration(Drawable offsetDrawable) {
mOffsetDrawable = offsetDrawable;
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
mOrientation = ((LinearLayoutManager) parent.getLayoutManager()).getOrientation();
if (mOrientation == LinearLayoutManager.HORIZONTAL) {
if (mOffsetPx > 0) {
outRect.left = mOffsetPx;
outRect.right = mOffsetPx;
} else if (mOffsetDrawable != null) {
outRect.left = mOffsetDrawable.getIntrinsicWidth();
outRect.right = mOffsetDrawable.getIntrinsicWidth();
}
} else if (mOrientation == LinearLayoutManager.VERTICAL) {
if (mOffsetPx > 0) {
outRect.top = mOffsetPx;
} else if (mOffsetDrawable != null) {
outRect.top = mOffsetDrawable.getIntrinsicHeight();
}
}
}
#Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
super.onDraw(c, parent, state);
if (mOffsetDrawable == null) {
return;
}
if (mOrientation == LinearLayoutManager.HORIZONTAL) {
drawOffsetHorizontal(c, parent);
} else if (mOrientation == LinearLayoutManager.VERTICAL) {
drawOffsetVertical(c, parent);
}
}
private void drawOffsetHorizontal(Canvas canvas, RecyclerView parent) {
int parentTop = parent.getPaddingTop();
int parentBottom = parent.getHeight() - parent.getPaddingBottom();
int parentLeft = parent.getPaddingLeft();
int offsetDrawableRight = parentLeft + mOffsetDrawable.getIntrinsicWidth();
mOffsetDrawable.setBounds(parentLeft, parentTop, offsetDrawableRight, parentBottom);
mOffsetDrawable.draw(canvas);
}
private void drawOffsetVertical(Canvas canvas, RecyclerView parent) {
int parentLeft = parent.getPaddingLeft();
int parentRight = parent.getWidth() - parent.getPaddingRight();
int parentTop = parent.getPaddingTop();
int offsetDrawableBottom = parentTop + mOffsetDrawable.getIntrinsicHeight();
mOffsetDrawable.setBounds(parentLeft, parentTop, parentRight, offsetDrawableBottom);
mOffsetDrawable.draw(canvas);
}
Thanks to author of the post David Greenhalgh and Shayan Pourvatan for the idea to create custom class

Related

How to show the view from bottom while recyclerview scrolling

I am having 15 to 30 items in my recyclerview. At the End of the recyclerview I want to show the Image/Layout at bottom. This image will slowly come to top while scroll the recylerview to top. When the list end the image/layout will fully shown. If we scroll down the recyclerview the image/layout should go down. If I stop the scroll at middle the image/layout will show partially. For example the Image/Layout height will be 100 dp. it will be placed in the bottom. It will not visible at first time. When we scroll the Recyclerview that view will be slowly appear. Please give me any idea to achieve this. Sorry for my bad English.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="vertical" />
<RelativeLayout
android:id="#+id/bottomView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Will show while Scroll"
android:textSize="30sp"
/>
</RelativeLayout>
</RelativeLayout>
Scrolling Recyclerview
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
if (dy > 0) {
footerHeight = +10;
bottomView.setTranslationY(footerHeight);
Log.i("Test","...Scrolling up");
} else {
footerHeight = -10;
bottomView.setTranslationY(footerHeight);
Log.i("Test","...Scrolling down");
}
}
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
switch (newState) {
case RecyclerView.SCROLL_STATE_IDLE:
Log.i("Test","...The RecyclerView is not scrolling");
break;
case RecyclerView.SCROLL_STATE_DRAGGING:
Log.i("Test","...Scrolling now");
break;
case RecyclerView.SCROLL_STATE_SETTLING:
Log.i("Test","...Scroll Settling");
break;
}
}
});
Here I just increase/decrease the bottomX view while scrolling. But still I am missing something.
OP:
In this image bottom view is showing always. But initially it want view should be hidden state. While scroll up Bottom view slowly come up. If I scroll down Bottom view should slowly goes down.
Start a new project and try this:
MainActivity.java:
public class MainActivity extends AppCompatActivity {
private static final int DATA_LIST_SIZE = 50;
RecyclerView recyclerView;
TextView footer;
ArrayList<SampleData> dataArrayList;
LinearLayoutManager linearLayoutManager;
int totalHeight = -1;
int invisibleHeight = -1;
int scrolledHeight = -1;
int childHeight = -1;
int footerHeight = -1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recycler_view);
footer = findViewById(R.id.text_view_footer);
dataArrayList = genSampleDataList();
CustomRecyclerViewAdapter adapter = new CustomRecyclerViewAdapter(dataArrayList);
linearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
recyclerView.setLayoutManager(linearLayoutManager);
recyclerView.setAdapter(adapter);
footer.measure( View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
footerHeight = footer.getMeasuredHeight();
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(#NonNull RecyclerView recyclerView, int dx, int dy) {
View firstVisibleView = recyclerView.getChildAt(0);
if (invisibleHeight == -1) {
childHeight = linearLayoutManager.getDecoratedMeasuredHeight(firstVisibleView);
totalHeight = childHeight * DATA_LIST_SIZE;
invisibleHeight = totalHeight - recyclerView.getHeight() + footerHeight;
}
scrolledHeight = linearLayoutManager.findFirstVisibleItemPosition() * childHeight +
recyclerView.getTop() - firstVisibleView.getTop();
int newRecyclerViewHeight = totalHeight - invisibleHeight + footerHeight -
scrolledHeight * footerHeight / invisibleHeight;
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, newRecyclerViewHeight);
recyclerView.setLayoutParams(params);
footer.setBackgroundColor(Color.rgb(255 * (invisibleHeight - scrolledHeight) / invisibleHeight,
255 * scrolledHeight / invisibleHeight, 0));
}
#Override
public void onScrollStateChanged(#NonNull RecyclerView recyclerView, int newState) {
}
});
}
private ArrayList<SampleData> genSampleDataList() {
ArrayList<SampleData> tmpList = new ArrayList<>();
for (int i = 0; i < DATA_LIST_SIZE; i++) {
tmpList.add(new SampleData("Item " + (i + 1), "Description " + (i + 1)));
}
return tmpList;
}
}
SampleData.java:
public class SampleData {
String name;
String description;
public SampleData(String name, String description) {
this.name = name;
this.description = description;
}
}
CustomRecyclerViewAdapter.java:
public class CustomRecyclerViewAdapter extends RecyclerView.Adapter<CustomRecyclerViewAdapter.ViewHolder> {
ArrayList<SampleData> dataList;
public CustomRecyclerViewAdapter(ArrayList<SampleData> dataList) {
this.dataList = dataList;
}
#NonNull
#Override
public ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_view, null);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull ViewHolder holder, int position) {
SampleData sampleData = dataList.get(position);
holder.textViewName.setText(sampleData.name);
holder.textViewDescription.setText(sampleData.description);
}
#Override
public int getItemCount() {
return dataList.size();
}
class ViewHolder extends RecyclerView.ViewHolder {
TextView textViewName;
TextView textViewDescription;
public ViewHolder(#NonNull View itemView) {
super(itemView);
textViewName = itemView.findViewById(R.id.text_view_name);
textViewDescription = itemView.findViewById(R.id.text_view_description);
}
}
}
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:scrollbars="vertical" />
<TextView
android:id="#+id/text_view_footer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/recycler_view"
android:gravity="center"
android:text="Will show while Scroll"
android:textSize="30sp" />
</RelativeLayout>
item_view.xml:
<TextView
android:id="#+id/text_view_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="25sp"
android:textStyle="bold" />
<TextView
android:id="#+id/text_view_description"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="20sp" />
</LinearLayout>
One solution if I've read your question correctly is in your model class to include link or Uri of ImageView in a String.
Then in your RecyclerView adapter do some boolean checking to see if item added has a link to it and if it has load it with library called Picasso for example. Picasso is simple just one line of code. If you are using image from phone you might just add uri to image.
And when items are added on last item add link to image or set it yourself.

View not appearing at bottom of CardView?

Hi I have a simple CardView where I want to show a divider between each Cardview. The issue is, my View that I use as a divider never gets shown on the last CardView in my RecyclerView. Here is my attempt:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
xmlns:fresco="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="100dp"
card_view:cardElevation="0dp"
android:id="#+id/cv_news_feed">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp">
...Content...
</RelativeLayout>
</LinearLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#color/material_color_grey_300" />
</android.support.v7.widget.CardView>
The divider shows up for every CardView except for the last for whatever reason and I'm not sure why this is occurring. Any help would be appreciated, thanks!
EDIT: Image posted:
Remove following view from your item
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#color/material_color_grey_300" />
and try to use ItemDecoration as follows
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(
Utility.ItemDecorationConst);
recyclerView.addItemDecoration(5);
DividerItemDecoration.java
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public DividerItemDecoration(int space) {
this.space = space;
}
#Override
public void getItemOffsets(Rect outRect, View view,
RecyclerView parent, RecyclerView.State state) {
outRect.left = space;
outRect.right = space;
outRect.top = space;
outRect.bottom = space;
}
}
CardView is an extension of FrameLayout which means that your divider is not in the bottom of your CardView but in the top.
Place your divider in your LinearLayout instead.
Add layout_gravity attribute to the View:
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_gravity="bottom"
android:background="#color/material_color_grey_300" />
You can try to this code , hope this can help you
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
xmlns:fresco="http://schemas.android.com/tools"
android:id="#+id/cv_news_feed"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="100dp"
card_view:cardElevation="0dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp">
...Content...
</RelativeLayout>
</LinearLayout>
</android.support.v7.widget.CardView>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_below="#+id/cv_news_feed"
android:layout_marginTop="5dp"
android:background="#android:color/holo_red_dark" />
</RelativeLayout>
Create a class DividerItemDecoration:
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.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
/**
* Created by Lincoln on 30/10/15.
*/
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{
android.R.attr.listDivider
};
public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
private Drawable mDivider;
private int mOrientation;
public DividerItemDecoration(Context context, int orientation) {
final TypedArray a = context.obtainStyledAttributes(ATTRS);
mDivider = a.getDrawable(0);
a.recycle();
setOrientation(orientation);
}
public void setOrientation(int orientation) {
if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
throw new IllegalArgumentException("invalid orientation");
}
mOrientation = orientation;
}
#Override
public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
if (mOrientation == VERTICAL_LIST) {
drawVertical(c, parent);
} else {
drawHorizontal(c, parent);
}
}
public void drawVertical(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 int top = child.getBottom() + params.bottomMargin;
final int bottom = top + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
public void drawHorizontal(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 int left = child.getRight() + params.rightMargin;
final int right = left + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
if (mOrientation == VERTICAL_LIST) {
outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
} else {
outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
}
}
}
Then set the item decoration using addItemDecoration() method before setting the adapter.
recyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));
// set the adapter
recyclerView.setAdapter(mAdapter);
N.B. Remove the view that you are using in cardview layout to show the divider.
Try to put your divider into LinearLayout,i.e.:
You should use like this
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp">
...Content...
</RelativeLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#color/material_color_grey_300" />
</LinearLayout>
Because CardView extends FrameLayout so your devider will be behind LinearLayout content.

recycler view gridmanager layout column spacing does not give equal space in all side

enter image description here//I have recycler view as follows in xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include layout="#layout/toolbar" />
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/grid_recycle_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipToPadding="false"
android:background="#f8f9fb"
/>
<android.support.v7.widget.RecyclerView
android:id="#+id/list_recycle_view"
android:visibility="invisible"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</FrameLayout>
</LinearLayout>
//in my onprepareGridView method i have done following
private void prepareGridRecycleView() {
gridRecyclerView.setHasFixedSize(true);
SpaceItemDecoration itemDecoration = new SpaceItemDecoration(10);
gridRecyclerView.setClipToPadding(false);
gridRecyclerView.addItemDecoration(itemDecoration);
adapter = new ShopPageGridViewAdapter(ShopPageContent.this, new ShopPageHeaderGridInterface() {
#Override
public void onClick(boolean isClicked) {
gridRecyclerView.setVisibility(View.INVISIBLE);
listRecycleView.setVisibility(View.VISIBLE);
}
}, new ShopPageHeaderListInterface() {
#Override
public void onClick(boolean isClicked) {
}
}, new CartCoordivateInfoHolder() {
#Override
public void setViewCoordinate(ImageView view, int x, int y) {
view.setVisibility(View.VISIBLE);
view.bringToFront();
view.invalidate();
int pos[] = new int[2];
cart.getLocationOnScreen(pos);
Log.e("x", String.valueOf(pos[0]));
Log.e("y", String.valueOf(pos[1]));
TranslateAnimation anim = new TranslateAnimation(0, pos[0] - x, 0, pos[1] - y);
anim.setDuration(5000);
anim.setFillAfter(true);
view.startAnimation(anim);
}
});
final GridLayoutManager manager = new GridLayoutManager(this, 2);
manager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
#Override
public int getSpanSize(int position) {
return adapter.isPositionHeader(position) ? manager.getSpanCount() : 1;
}
});
gridRecyclerView.setAdapter(adapter);
gridRecyclerView.setLayoutManager(manager);
}
//and the item decorator class looks like the following
public class SpaceItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public SpaceItemDecoration(int space) {
this.space = space;
}
#Override
public void getItemOffsets(Rect outRect, View view,
RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view);
if (position == 0) {
outRect.left = 0;
outRect.right = 0;
outRect.bottom = 0;
outRect.top = 0;
return;
}
if (parent.getChildAdapterPosition(view) == 1 || parent.getChildAdapterPosition(view) == 2) {
outRect.top = 0;
outRect.left =(space);
outRect.right = space;
outRect.bottom = space;
return;
}
outRect.left = space;[enter image description here][1]
outRect.right = space;
outRect.bottom = space;
outRect.top = space;
}
}
//The problem i am facing is space at the left side and right side different. Left side space are smaller than the right side space.
//image link
Try to:
public class SpaceItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public SpaceItemDecoration(int space) {
this.space = space;
}
#Override
public void getItemOffsets(Rect outRect, View view,
RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view);
outRect.left = space;
outRect.right = space;
outRect.bottom = space;
outRect.top = space;
if(position%2==0){
outRect.left = 0;
}
}
}
This code is not tested;

Dividers didn't display in RecyclerView after addItemDecoration() called

A RecyclerView is nested in a CardView. I tried to call addItemDecoration() to add dividers into RecycylerView,but it didn't work.
<android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
card_view:cardBackgroundColor="#color/white_color"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
card_view:cardElevation="3dp">
<android.support.v4.widget.SwipeRefreshLayout
android:id="#+id/swipe_saleproduct_list"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_saleproduct_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:visibility="visible" />
</android.support.v4.widget.SwipeRefreshLayout>
</android.support.v7.widget.CardView>
The java code:
mSwipe = (SwipeRefreshLayout)view.findViewById(R.id.swipe_saleproduct_list);
mRecyclerView= (RecyclerView) view.findViewById(R.id.recycler_saleproduct_list);
mRecyclerView.setLayoutManager(new LinearLayoutManager(UIUtils.getContext()));
mRecyclerView.addItemDecoration(new DividerItemDecoration(UIUtils.getContext(), DividerItemDecoration.VERTICAL_LIST));
SaleProductListAdapter saleProductListAdapter = new SaleProductListAdapter(UIUtils.getContext(), mRecyclerView, list, mSwipe);
mRecyclerView.setAdapter(saleProductListAdapter);
This below is a good example, take a look at it:
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{
android.R.attr.listDivider
};
public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
private Drawable mDivider;
private int mOrientation;
public DividerItemDecoration(Context context, int orientation) {
final TypedArray a = context.obtainStyledAttributes(ATTRS);
mDivider = a.getDrawable(0);
a.recycle();
setOrientation(orientation);
}
public void setOrientation(int orientation) {
if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
throw new IllegalArgumentException("invalid orientation");
}
mOrientation = orientation;
}
#Override
public void onDraw(Canvas c, RecyclerView parent) {
if (mOrientation == VERTICAL_LIST) {
drawVertical(c, parent);
} else {
drawHorizontal(c, parent);
}
}
public void drawVertical(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 int top = child.getBottom() + params.bottomMargin;
final int bottom = top + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
public void drawHorizontal(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 int left = child.getRight() + params.rightMargin;
final int right = left + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
#Override
public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
if (mOrientation == VERTICAL_LIST) {
outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
} else {
outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
}
}
}
And here is my Fragment, it works well, which divider is clear and thin:
public static class RecyclerViewFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_recyclerview, container, false);
RecyclerView recyclerView = (RecyclerView) root.findViewById(R.id.recycler_view);
recyclerView.setHasFixedSize(true);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerView.addItemDecoration(new DividerItemDecoration(getActivity(), DividerItemDecoration.VERTICAL_LIST));
RecyclerViewAdapter adapter = new RecyclerViewAdapter(getActivity(), getResources()
.getStringArray(R.array.countries));
recyclerView.setAdapter(adapter);
return root;
}
}
I hope you will be inspired.
The mDivider with System maybe NullPointerException on platform KitKat and below,so I suggest use mDivider with oneself like:
public MyDecoration(Context context, int orientation) {
mDivider = context.getResources().getDrawable(R.drawable.line_divider);
setOrientation(orientation);
}
And Here is the line_divider:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size
android:width="1dp"
android:height="1dp" />
<solid android:color="#color/color_in_common_green" />
</shape>
It maybe work well

How to add dividers and spaces between items in RecyclerView

This is an example of how it could have been done previously in the ListView class, using the divider and dividerHeight parameters:
<ListView
android:id="#+id/activity_home_list_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:divider="#android:color/transparent"
android:dividerHeight="8dp"/>
However, I don't see such possibility in the RecyclerView class.
<android.support.v7.widget.RecyclerView
android:id="#+id/activity_home_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="vertical"/>
In that case, is it ok to define margins and/or add a custom divider view directly into a list item's layout or is there a better way to achieve my goal?
October 2016 Update
The version 25.0.0 of Android Support Library introduced the DividerItemDecoration class:
DividerItemDecoration is a RecyclerView.ItemDecoration that can be used as a divider between items of a LinearLayoutManager. It supports both HORIZONTAL and VERTICAL orientations.
Usage:
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(),
layoutManager.getOrientation());
recyclerView.addItemDecoration(dividerItemDecoration);
Previous answer
Some answers either use methods that have since become deprecated, or don't give a complete solution, so I tried to do a short, up-to-date wrap-up.
Unlike ListView, the RecyclerView class doesn't have any divider-related parameters. Instead, you need to extend ItemDecoration, a RecyclerView's inner class:
An ItemDecoration allows the application to add a special drawing and layout offset to specific item views from the adapter's data set. This can be useful for drawing dividers between items, highlights, visual grouping boundaries and more.
All ItemDecorations are drawn in the order they were added, before the item views (in onDraw()) and after the items (in onDrawOver(Canvas, RecyclerView, RecyclerView.State).
Vertical spacing ItemDecoration
Extend ItemDecoration, add a custom constructor which takes space height as a parameter and override the getItemOffsets() method:
public class VerticalSpaceItemDecoration extends RecyclerView.ItemDecoration {
private final int verticalSpaceHeight;
public VerticalSpaceItemDecoration(int verticalSpaceHeight) {
this.verticalSpaceHeight = verticalSpaceHeight;
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
RecyclerView.State state) {
outRect.bottom = verticalSpaceHeight;
}
}
If you don't want to insert space below the last item, add the following condition:
if (parent.getChildAdapterPosition(view) != parent.getAdapter().getItemCount() - 1) {
outRect.bottom = verticalSpaceHeight;
}
Note: you can also modify outRect.top, outRect.left and outRect.right properties for the desired effect.
Divider ItemDecoration
Extend ItemDecoration and override the onDraw() method:
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
private Drawable divider;
/**
* Default divider will be used
*/
public DividerItemDecoration(Context context) {
final TypedArray styledAttributes = context.obtainStyledAttributes(ATTRS);
divider = styledAttributes.getDrawable(0);
styledAttributes.recycle();
}
/**
* Custom divider will be used
*/
public DividerItemDecoration(Context context, int resId) {
divider = ContextCompat.getDrawable(context, resId);
}
#Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
int left = parent.getPaddingLeft();
int right = parent.getWidth() - parent.getPaddingRight();
int childCount = parent.getChildCount();
for (int i = 0; i < childCount; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
int top = child.getBottom() + params.bottomMargin;
int bottom = top + divider.getIntrinsicHeight();
divider.setBounds(left, top, right, bottom);
divider.draw(c);
}
}
}
You can either call the first constructor that uses the default Android divider attributes, or the second one that uses your own drawable, for example drawable/divider.xml:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size android:height="1dp" />
<solid android:color="#ff992900" />
</shape>
Note: if you want the divider to be drawn over your items, override the onDrawOver() method instead.
Usage
To use your new class, add VerticalSpaceItemDecoration or DividerSpaceItemDecoration to RecyclerView, for example in your fragment's onCreateView() method:
private static final int VERTICAL_ITEM_SPACE = 48;
private RecyclerView recyclerView;
private LinearLayoutManager linearLayoutManager;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_feed, container, false);
recyclerView = (RecyclerView) rootView.findViewById(R.id.fragment_home_recycler_view);
linearLayoutManager = new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(linearLayoutManager);
//add ItemDecoration
recyclerView.addItemDecoration(new VerticalSpaceItemDecoration(VERTICAL_ITEM_SPACE));
//or
recyclerView.addItemDecoration(new DividerItemDecoration(getActivity()));
//or
recyclerView.addItemDecoration(
new DividerItemDecoration(getActivity(), R.drawable.divider));
recyclerView.setAdapter(...);
return rootView;
}
There's also Lucas Rocha's library which is supposed to simplify the item decoration process. I haven't tried it though.
Among its features are:
A collection of stock item decorations including:
Item spacing Horizontal/vertical dividers.
List item
Just add
recyclerView.addItemDecoration(new DividerItemDecoration(getContext(),
DividerItemDecoration.VERTICAL));
Also you may need to add the dependency
implementation 'com.android.support:recyclerview-v7:28.0.0'
For customizing it a little bit you can add a custom drawable:
DividerItemDecoration itemDecorator = new DividerItemDecoration(getContext(), DividerItemDecoration.VERTICAL);
itemDecorator.setDrawable(ContextCompat.getDrawable(getContext(), R.drawable.divider));
You are free to use any custom drawable, for instance:
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#color/colorPrimary"/>
<size android:height="0.5dp"/>
</shape>
Might I direct your attention to this particular file on GitHub by Alex Fu:
link
It's the DividerItemDecoration.java example file "pulled straight from the support demos".
I was able to get divider lines nicely after importing this file in my project and add it as an item decoration to the recycler view.
Here's how my onCreateView look like in my fragment containing the Recyclerview:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_recycler_view, container, false);
mRecyclerView = (RecyclerView) rootView.findViewById(R.id.my_recycler_view);
mRecyclerView.addItemDecoration(new DividerItemDecoration(getActivity(), DividerItemDecoration.VERTICAL));
mRecyclerView.setHasFixedSize(true);
mLayoutManager = new LinearLayoutManager(getActivity());
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setItemAnimator(new DefaultItemAnimator());
return rootView;
}
I'm sure additional styling can be done, but it's a starting point. :)
A simple ItemDecoration implementation for equal spaces between all items:
public class SpacesItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public SpacesItemDecoration(int space) {
this.space = space;
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
outRect.left = space;
outRect.right = space;
outRect.bottom = space;
// Add top margin only for the first item to avoid double space between items
if(parent.getChildAdapterPosition(view) == 0) {
outRect.top = space;
}
}
}
The simple one is to set the background color for RecyclerView and a different background color for items. Here is an example...
<android.support.v7.widget.RecyclerView
android:background="#ECEFF1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="vertical"/>
And the TextView item (it can be anything though) with bottom margin "x" dp or px.
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginBottom="1dp"
android:background="#FFFFFF"/>
The output...
This is simple, and you don't need such complicated code:
DividerItemDecoration divider = new DividerItemDecoration(
mRVMovieReview.getContext(), DividerItemDecoration.VERTICAL
);
divider.setDrawable(
ContextCompat.getDrawable(getBaseContext(), R.drawable.line_divider)
);
mRVMovieReview.addItemDecoration(divider);
Add this in your drawable: line_divider.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size android:height="1dp" />
<solid android:color="#android:color/black" />
</shape>
The way how I'm handling the Divider view and also Divider Insets is by adding a RecyclerView extension.
1.
Add a new extension file by naming View or RecyclerView:
RecyclerViewExtension.kt
and add the setDivider extension method inside the RecyclerViewExtension.kt file.
/*
* RecyclerViewExtension.kt
* */
import androidx.annotation.DrawableRes
import androidx.core.content.ContextCompat
import androidx.recyclerview.widget.DividerItemDecoration
import androidx.recyclerview.widget.RecyclerView
fun RecyclerView.setDivider(#DrawableRes drawableRes: Int) {
val divider = DividerItemDecoration(
this.context,
DividerItemDecoration.VERTICAL
)
val drawable = ContextCompat.getDrawable(
this.context,
drawableRes
)
drawable?.let {
divider.setDrawable(it)
addItemDecoration(divider)
}
}
2.
Create a Drawable resource file inside of drawable package like recycler_view_divider.xml:
<inset xmlns:android="http://schemas.android.com/apk/res/android"
android:insetLeft="10dp"
android:insetRight="10dp">
<shape>
<size android:height="0.5dp" />
<solid android:color="#android:color/darker_gray" />
</shape>
</inset>
where you can specify the left and right margin on android:insetLeft and android:insetRight.
3.
On your Activity or Fragment where the RecyclerView is initialized, you can set the custom drawable by calling:
recyclerView.setDivider(R.drawable.recycler_view_divider)
4.
Cheers 🍺
As I have set ItemAnimators. The ItemDecorator don't enter or exit along with the animation.
I simply ended up in having a view line in my item view layout file of each item. It solved my case. DividerItemDecoration felt to be too much of sorcery for a simple divider.
<View
android:layout_width="match_parent"
android:layout_height="1px"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:background="#color/lt_gray"/>
I think using a simple divider will help you
To add divider to each item:
1. Add this to drawable directory line_divider.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size
android:width="1dp"
android:height="1dp" />
<solid android:color="#999999" />
</shape>
2. Create SimpleDividerItemDecoration class
I used this example to define this class:
https://gist.github.com/polbins/e37206fbc444207c0e92
package com.example.myapp;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import com.example.myapp.R;
public class SimpleDividerItemDecoration extends RecyclerView.ItemDecoration{
private Drawable mDivider;
public SimpleDividerItemDecoration(Resources resources) {
mDivider = resources.getDrawable(R.drawable.line_divider);
}
public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
int left = parent.getPaddingLeft();
int right = parent.getWidth() - parent.getPaddingRight();
int childCount = parent.getChildCount();
for (int i = 0; i < childCount; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
int top = child.getBottom() + params.bottomMargin;
int bottom = top + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
}
3. In activity or fragment that using RecyclerView, inside onCreateView add this:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
RecyclerView myRecyclerView = (RecyclerView) layout.findViewById(R.id.my_recycler_view);
myRecyclerView.addItemDecoration(new SimpleDividerItemDecoration(getResources()));
....
}
4. To add spacing between Items
You just need to add padding property to your item view
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:padding="4dp"
>
..... item structure
</RelativeLayout>
If anyone is looking to only add, say, 10 dp spacing between items, you can do so by setting a drawable to DividerItemDecoration:
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(
recyclerView.getContext(),
layoutManager.getOrientation()
);
dividerItemDecoration.setDrawable(
ContextCompat.getDrawable(getContext(), R.drawable.divider_10dp)
);
recyclerView.addItemDecoration(dividerItemDecoration);
Where divider_10dpis a drawable resource containing:
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
<size android:height="10dp"/>
<solid android:color="#android:color/transparent"/>
</shape>
Since there is no right way to implement this yet properly using Material Design, I just did the following trick to add a divider on the list item directly:
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#color/dividerColor"/>
Instead of creating a shape xml for changing the divider height and color, you can create it programmatically like:
val divider = DividerItemDecoration(
context,
DividerItemDecoration.VERTICAL)
divider.setDrawable(ShapeDrawable().apply {
intrinsicHeight = resources.getDimensionPixelOffset(R.dimen.dp_15)
paint.color = Color.RED // Note:
// Currently (support version 28.0.0), we
// can not use tranparent color here. If
// we use transparent, we still see a
// small divider line. So if we want
// to display transparent space, we
// can set color = background color
// or we can create a custom ItemDecoration
// instead of DividerItemDecoration.
})
recycler_devices.addItemDecoration(divider)
OCTOBER 2016 UPDATE
With support library v25.0.0 there finally is a default implementation of basic horizontal and vertical dividers available!
DividerItemDecoration
Add a margin to your view. It worked for me.
android:layout_marginTop="10dp"
If you just want to add equal spacing and want to do it in XML, just set padding to your RecyclerView and equal amount of layoutMargin to the item you inflate into your RecyclerView, and let the background color determine the spacing color.
For those who are looking just for spaces between items in the RecyclerView, see my approach where you get equal spaces between all items, except in the first and last items where I gave a bigger padding. I only apply padding to left/right in a horizontal LayoutManager and to top/bottom in a vertical LayoutManager.
public class PaddingItemDecoration extends RecyclerView.ItemDecoration {
private int mPaddingPx;
private int mPaddingEdgesPx;
public PaddingItemDecoration(Activity activity) {
final Resources resources = activity.getResources();
mPaddingPx = (int) resources.getDimension(R.dimen.paddingItemDecorationDefault);
mPaddingEdgesPx = (int) resources.getDimension(R.dimen.paddingItemDecorationEdge);
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
final int itemPosition = parent.getChildAdapterPosition(view);
if (itemPosition == RecyclerView.NO_POSITION) {
return;
}
int orientation = getOrientation(parent);
final int itemCount = state.getItemCount();
int left = 0;
int top = 0;
int right = 0;
int bottom = 0;
/** Horizontal */
if (orientation == LinearLayoutManager.HORIZONTAL) {
/** All positions */
left = mPaddingPx;
right = mPaddingPx;
/** First position */
if (itemPosition == 0) {
left += mPaddingEdgesPx;
}
/** Last position */
else if (itemCount > 0 && itemPosition == itemCount - 1) {
right += mPaddingEdgesPx;
}
}
/** Vertical */
else {
/** All positions */
top = mPaddingPx;
bottom = mPaddingPx;
/** First position */
if (itemPosition == 0) {
top += mPaddingEdgesPx;
}
/** Last position */
else if (itemCount > 0 && itemPosition == itemCount - 1) {
bottom += mPaddingEdgesPx;
}
}
if (!isReverseLayout(parent)) {
outRect.set(left, top, right, bottom);
} else {
outRect.set(right, bottom, left, top);
}
}
private boolean isReverseLayout(RecyclerView parent) {
if (parent.getLayoutManager() instanceof LinearLayoutManager) {
LinearLayoutManager layoutManager = (LinearLayoutManager) parent.getLayoutManager();
return layoutManager.getReverseLayout();
} else {
throw new IllegalStateException("PaddingItemDecoration can only be used with a LinearLayoutManager.");
}
}
private int getOrientation(RecyclerView parent) {
if (parent.getLayoutManager() instanceof LinearLayoutManager) {
LinearLayoutManager layoutManager = (LinearLayoutManager) parent.getLayoutManager();
return layoutManager.getOrientation();
} else {
throw new IllegalStateException("PaddingItemDecoration can only be used with a LinearLayoutManager.");
}
}
}
File dimens.xml
<resources>
<dimen name="paddingItemDecorationDefault">10dp</dimen>
<dimen name="paddingItemDecorationEdge">20dp</dimen>
</resources>
Here is a simple hack to add a divider
Just add a background to the layout of your recycler item as follows
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/shape_border"
android:gravity="center"
android:orientation="horizontal"
android:padding="5dp">
<ImageView
android:id="#+id/imageViewContactLogo"
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_marginRight="10dp"
android:src="#drawable/ic_user" />
<LinearLayout
android:id="#+id/linearLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0.92"
android:gravity="center|start"
android:orientation="vertical">
<TextView
android:id="#+id/textViewContactName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:singleLine="true"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="#+id/textViewStatusOrNumber"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:singleLine="true"
android:text=""
android:textAppearance="?android:attr/textAppearanceMedium" />
</LinearLayout>
<TextView
android:id="#+id/textViewUnreadCount"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="10dp"
android:padding="5dp"
android:text=""
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#color/red"
android:textSize="22sp" />
<Button
android:id="#+id/buttonInvite"
android:layout_width="54dp"
android:layout_height="wrap_content"
android:background="#drawable/ic_add_friend" />
</LinearLayout>
Create the following shape_border.xml file in the drawable folder:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle" >
<gradient
android:angle="270"
android:centerColor="#android:color/transparent"
android:centerX="0.01"
android:startColor="#000" />
</shape>
Here is the final result - a RecyclerView with divider.
This doesn't actually solve the problem, but as a temporary workaround, you can set the useCompatPadding property on the card in your XML layout to make it measure the same as it does on pre-Lollipop versions.
card_view:cardUseCompatPadding="true"
I forked the DividerItemDecoration from an older gist and simplified it to fit my use case, and I also modified it to draw the dividers the way they are drawn in ListView, including a divider after the last list item. This will also handle vertical ItemAnimator animations:
1) Add this class to your project:
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
private Drawable divider;
public DividerItemDecoration(Context context) {
try {
final TypedArray a = context.obtainStyledAttributes(ATTRS);
divider = a.getDrawable(0);
a.recycle();
} catch (Resources.NotFoundException e) {
// TODO Log or handle as necessary.
}
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
if (divider == null) return;
if (parent.getChildAdapterPosition(view) < 1) return;
if (getOrientation(parent) == LinearLayoutManager.VERTICAL)
outRect.top = divider.getIntrinsicHeight();
else
throw new IllegalArgumentException("Only usable with vertical lists");
}
#Override
public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
if (divider == null) {
super.onDrawOver(c, parent, state);
return;
}
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 int size = divider.getIntrinsicHeight();
final int top = (int) (child.getTop() - params.topMargin - size + child.getTranslationY());
final int bottom = top + size;
divider.setBounds(left, top, right, bottom);
divider.draw(c);
if (i == childCount - 1) {
final int newTop = (int) (child.getBottom() + params.bottomMargin + child.getTranslationY());
final int newBottom = newTop + size;
divider.setBounds(left, newTop, right, newBottom);
divider.draw(c);
}
}
}
private int getOrientation(RecyclerView parent) {
if (!(parent.getLayoutManager() instanceof LinearLayoutManager))
throw new IllegalStateException("Layout manager must be an instance of LinearLayoutManager");
return ((LinearLayoutManager) parent.getLayoutManager()).getOrientation();
}
}
2) Add the decorator to your RecylerView:
recyclerView.addItemDecoration(new DividerItemDecoration(getActivity()));
I feel like there's a need for a simple, code-based answer that doesn't use XML
DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(), DividerItemDecoration.VERTICAL);
ShapeDrawable shapeDrawableForDivider = new ShapeDrawable(new RectShape());
int dividerThickness = // (int) (SomeOtherView.getHeight() * desiredPercent);
shapeDrawableForDivider.setIntrinsicHeight(dividerThickness);
shapeDrawableForDivider.setAlpha(0);
dividerItemDecoration.setDrawable(shapeDrawableForDivider);
recyclerView.addItemDecoration(dividerItemDecoration);
I love this answer so much, I re-wrote it in a single-expression Kotlin answer:
recyclerView.addItemDecoration(DividerItemDecoration(this,DividerItemDecoration.VERTICAL).also { deco ->
with (ShapeDrawable(RectShape())){
intrinsicHeight = (resources.displayMetrics.density * 24).toInt()
alpha = 0
deco.setDrawable(this)
}
})
This does the same thing as #Nerdy's original answer, except it sets the height of the divider to 24dp instead of a percentage of another view's height.
Here's a decoration that lets you set a spacing between items as well as a spacing on the edges. This works for both HORIZONTAL and VERTICAL layouts.
class LinearSpacingDecoration(
#Px private val itemSpacing: Int,
#Px private val edgeSpacing: Int = 0
): RecyclerView.ItemDecoration() {
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
val count = parent.adapter?.itemCount ?: 0
val position = parent.getChildAdapterPosition(view)
val leading = if (position == 0) edgeSpacing else itemSpacing
val trailing = if (position == count - 1) edgeSpacing else 0
outRect.run {
if ((parent.layoutManager as? LinearLayoutManager)?.orientation == LinearLayout.VERTICAL) {
top = leading
bottom = trailing
} else {
left = leading
right = trailing
}
}
}
}
Usage:
recyclerView.addItemDecoration(LinearSpacingDecoration(itemSpacing = 10, edgeSpacing = 20))
Taken from a Google search, add this ItemDecoration to your RecyclerView:
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private Drawable mDivider;
private boolean mShowFirstDivider = false;
private boolean mShowLastDivider = false;
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(Context context, AttributeSet attrs, boolean showFirstDivider,
boolean showLastDivider) {
this(context, attrs);
mShowFirstDivider = showFirstDivider;
mShowLastDivider = showLastDivider;
}
public DividerItemDecoration(Drawable divider) {
mDivider = divider;
}
public DividerItemDecoration(Drawable divider, boolean showFirstDivider,
boolean showLastDivider) {
this(divider);
mShowFirstDivider = showFirstDivider;
mShowLastDivider = showLastDivider;
}
#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, RecyclerView.State state) {
if (mDivider == null) {
super.onDrawOver(c, parent, state);
return;
}
// Initialization needed to avoid compiler warning
int left = 0, right = 0, top = 0, bottom = 0, size;
int orientation = getOrientation(parent);
int childCount = parent.getChildCount();
if (orientation == LinearLayoutManager.VERTICAL) {
size = mDivider.getIntrinsicHeight();
left = parent.getPaddingLeft();
right = parent.getWidth() - parent.getPaddingRight();
} else { // Horizontal
size = mDivider.getIntrinsicWidth();
top = parent.getPaddingTop();
bottom = parent.getHeight() - parent.getPaddingBottom();
}
for (int i = mShowFirstDivider ? 0 : 1; i < childCount; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
if (orientation == LinearLayoutManager.VERTICAL) {
top = child.getTop() - params.topMargin;
bottom = top + size;
} else { // Horizontal
left = child.getLeft() - params.leftMargin;
right = left + size;
}
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
// Show the last divider
if (mShowLastDivider && childCount > 0) {
View child = parent.getChildAt(childCount - 1);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
if (orientation == LinearLayoutManager.VERTICAL) {
top = child.getBottom() + params.bottomMargin;
bottom = top + size;
} else { // hHorizontal
left = child.getRight() + params.rightMargin;
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.");
}
}
}
This link worked like a charm for me:
https://gist.github.com/lapastillaroja/858caf1a82791b6c1a36
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.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.view.View;
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private Drawable mDivider;
private boolean mShowFirstDivider = false;
private boolean mShowLastDivider = false;
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(Context context, AttributeSet attrs, boolean showFirstDivider,
boolean showLastDivider) {
this(context, attrs);
mShowFirstDivider = showFirstDivider;
mShowLastDivider = showLastDivider;
}
public DividerItemDecoration(Drawable divider) {
mDivider = divider;
}
public DividerItemDecoration(Drawable divider, boolean showFirstDivider,
boolean showLastDivider) {
this(divider);
mShowFirstDivider = showFirstDivider;
mShowLastDivider = showLastDivider;
}
#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, RecyclerView.State state) {
if (mDivider == null) {
super.onDrawOver(c, parent, state);
return;
}
// Initialization needed to avoid compiler warning
int left = 0, right = 0, top = 0, bottom = 0, size;
int orientation = getOrientation(parent);
int childCount = parent.getChildCount();
if (orientation == LinearLayoutManager.VERTICAL) {
size = mDivider.getIntrinsicHeight();
left = parent.getPaddingLeft();
right = parent.getWidth() - parent.getPaddingRight();
} else { //horizontal
size = mDivider.getIntrinsicWidth();
top = parent.getPaddingTop();
bottom = parent.getHeight() - parent.getPaddingBottom();
}
for (int i = mShowFirstDivider ? 0 : 1; i < childCount; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
if (orientation == LinearLayoutManager.VERTICAL) {
top = child.getTop() - params.topMargin;
bottom = top + size;
} else { //horizontal
left = child.getLeft() - params.leftMargin;
right = left + size;
}
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
// show last divider
if (mShowLastDivider && childCount > 0) {
View child = parent.getChildAt(childCount - 1);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
if (orientation == LinearLayoutManager.VERTICAL) {
top = child.getBottom() + params.bottomMargin;
bottom = top + size;
} else { // horizontal
left = child.getRight() + params.rightMargin;
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.");
}
}
}
Then in your activity:
mCategoryRecyclerView.addItemDecoration(
new DividerItemDecoration(this, null));
Or this if you are using a fragment:
mCategoryRecyclerView.addItemDecoration(
new DividerItemDecoration(getActivity(), null));
We can decorate the items using various decorators attached to the recyclerview such as the DividerItemDecoration:
Simply use the following ...taken from the answer byEyesClear:
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
private Drawable mDivider;
/**
* Default divider will be used
*/
public DividerItemDecoration(Context context) {
final TypedArray styledAttributes = context.obtainStyledAttributes(ATTRS);
mDivider = styledAttributes.getDrawable(0);
styledAttributes.recycle();
}
/**
* Custom divider will be used
*/
public DividerItemDecoration(Context context, int resId) {
mDivider = ContextCompat.getDrawable(context, resId);
}
#Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
int left = parent.getPaddingLeft();
int right = parent.getWidth() - parent.getPaddingRight();
int childCount = parent.getChildCount();
for (int i = 0; i < childCount; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
int top = child.getBottom() + params.bottomMargin;
int bottom = top + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
}
And then use the above as follows:
RecyclerView.ItemDecoration itemDecoration = new DividerItemDecoration(this, DividerItemDecoration.VERTICAL_LIST);
recyclerView.addItemDecoration(itemDecoration);
This will display dividers between each item within the list as shown below:
And for those of who are looking for more details can check out this guide Using the RecyclerView _ CodePath Android Cliffnotes.
Some answers here suggest the use of margins, but the catch is that:
If you add both top and bottom margins, they will appear both added between items and they will be too large. If you only add either, there will be no margin either at the top or the bottom of the whole list. If you add half of the distance at the top, half at the bottom, the outer margins will be too small.
Thus, the only aesthetically correct solution is the divider that the system knows where to apply properly: between items, but not above or below items.
For GridLayoutManager I use this:
public class GridSpacesItemDecoration : RecyclerView.ItemDecoration
{
private int space;
public GridSpacesItemDecoration(int space) {
this.space = space;
}
public override void GetItemOffsets(Android.Graphics.Rect outRect, View view, RecyclerView parent, RecyclerView.State state)
{
var position = parent.GetChildLayoutPosition(view);
/// Only for GridLayoutManager Layouts
var manager = parent.GetLayoutManager() as GridLayoutManager;
if (parent.GetChildLayoutPosition(view) < manager.SpanCount)
outRect.Top = space;
if (position % 2 != 0) {
outRect.Right = space;
}
outRect.Left = space;
outRect.Bottom = space;
}
}
This works for any span count you have.
You can easily add it programmatically.
If your Layout Manager is Linearlayout then you can use:
DividerItemDecoration is a RecyclerView.ItemDecoration that can be
used as a divider between items of a LinearLayoutManager. It supports
both HORIZONTAL and VERTICAL orientations.
mDividerItemDecoration =
new DividerItemDecoration(recyclerView.getContext(),
mLayoutManager.getOrientation());
recyclerView.addItemDecoration(mDividerItemDecoration);
Source
If you want to add the same space for items, the simplest way is to add top+left padding for RecycleView and right+bottom margins to card items.
File dimens.xml
<resources>
<dimen name="divider">1dp</dimen>
</resources>
File list_item.xml
<CardView
android:layout_marginBottom="#dimen/divider"
android:layout_marginRight="#dimen/divider">
...
</CardView>
File list.xml
<RecyclerView
...
android:paddingLeft="#dimen/divider"
android:paddingTop="#dimen/divider" />
In order to accomplish spacing between items in a RecylerView, we can use ItemDecorators:
addItemDecoration(object : RecyclerView.ItemDecoration() {
override fun getItemOffsets(
outRect: Rect,
view: View,
parent: RecyclerView,
state: RecyclerView.State,
) {
super.getItemOffsets(outRect, view, parent, state)
if (parent.getChildAdapterPosition(view) > 0) {
outRect.top = 8.dp // Change this value with anything you want. Remember that you need to convert integers to pixels if you are working with dps :)
}
}
})
A few things to have in consideration given the code I pasted:
You don't really need to call super.getItemOffsets but I chose to, because I want to extend the behavior defined by the base class. If the library got an update doing more logic behind the scenes, we would miss it.
As an alternative to adding top spacing to the Rect, you could also add bottom spacing, but the logic related to getting the last item of the adapter is more complex, so this might be slightly better.
I used an extension property to convert a simple integer to dps: 8.dp. Something like this might work:
val Int.dp: Int
get() = (this * Resources.getSystem().displayMetrics.density + 0.5f).toInt()
// Extension function works too, but invoking it would become something like 8.dp()
I have added a line in a list item like below:
<View
android:id="#+id/divider"
android:layout_width="match_parent"
android:layout_height="1px"
android:background="#color/dividerColor"/>
"1px" will draw the thin line.
If you want to hide the divider for the last row, then use divider.setVisiblity(View.GONE); on the onBindViewHolder for the last list Item.
One of the ways is by using the cardview and recycler view together. We can easily add an effect, like a divider.
Example: Create dynamic lists with RecyclerView
And another is by adding a view as a divider to a list_item_layout of a recycler view.
<View
android:id="#+id/view1"
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#color/colorAccent" />
public class CommonItemSpaceDecoration extends RecyclerView.ItemDecoration {
private int mSpace = 0;
private boolean mVerticalOrientation = true;
public CommonItemSpaceDecoration(int space) {
this.mSpace = space;
}
public CommonItemSpaceDecoration(int space, boolean verticalOrientation) {
this.mSpace = space;
this.mVerticalOrientation = verticalOrientation;
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
outRect.top = SizeUtils.dp2px(view.getContext(), mSpace);
if (mVerticalOrientation) {
if (parent.getChildAdapterPosition(view) == 0) {
outRect.set(0, SizeUtils.dp2px(view.getContext(), mSpace), 0, SizeUtils.dp2px(view.getContext(), mSpace));
} else {
outRect.set(0, 0, 0, SizeUtils.dp2px(view.getContext(), mSpace));
}
} else {
if (parent.getChildAdapterPosition(view) == 0) {
outRect.set(SizeUtils.dp2px(view.getContext(), mSpace), 0, 0, 0);
} else {
outRect.set(SizeUtils.dp2px(view.getContext(), mSpace), 0, SizeUtils.dp2px(view.getContext(), mSpace), 0);
}
}
}
}
This will add space in every item's top and bottom (or left and right). Then you can set it to your recyclerView.
recyclerView.addItemDecoration(new CommonItemSpaceDecoration(16));
File SizeUtils.java
public class SizeUtils {
public static int dp2px(Context context, float dpValue) {
final float scale = context.getResources().getDisplayMetrics().density;
return (int) (dpValue * scale + 0.5f);
}
}

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