How to center items of a recyclerview?

I need to center elements in each row so they will be like in this mockup. I've been searching if there is any layout that works that way without look. items are centered in their rows.

This is how it looks now in my code.

Make recyclerview width to wrap_content and its container's layout_gravity to center_horizontal

 <LinearLayout
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:orientation="vertical">

      <android.support.v7.widget.RecyclerView
           android:id="@+id/recycrer_view"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:layout_gravity="center_horizontal"
           android:paddingLeft="16dp"
           android:paddingRight="16dp" />
 </LinearLayout>

Take LinearLayout in your RecyclerView's item row layout then give android:layout_gravity="center" to LinearLayout.

For each row of images you have to take different LinearLayout.

Here is example code:

 <LinearLayout
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_gravity="center"
         android:orientation="horizontal">

            <ImageView
                android:id="@+id/image1"
                android:layout_width="64dp"
                android:layout_height="64dp"
                android:layout_marginRight="10dp"
                android:layout_weight="1"
                android:src="@drawable/image1" />

            <ImageView
                android:id="@+id/image2"
                android:layout_width="64dp"
                android:layout_height="64dp"
                android:layout_marginLeft="10dp"
                android:layout_marginRight="10dp"
                android:layout_weight="1"
                android:src="@drawable/image2" />

           <ImageView
                android:id="@+id/image3"
                android:layout_width="64dp"
                android:layout_height="64dp"
                android:layout_marginLeft="10dp"
                android:layout_marginRight="10dp"
                android:layout_weight="1"
                android:src="@drawable/image3" />

  </LinearLayout>

Achieved with:

recyclerView.adapter = MyAdapter()
val layoutManager = FlexboxLayoutManager(context).apply {
    justifyContent = JustifyContent.CENTER
    alignItems = AlignItems.CENTER
    flexDirection = FlexDirection.ROW 
    flexWrap = FlexWrap.WRAP
}
recyclerView.layoutManager = layoutManager

I am assuming that you are using a LinearLayoutManager with a RecyclerView for a ListView-style effect. In that case, use a horizontal LinearLayout for each row, with android:gravity="center" to center its contents.

Use FlexboxLayout from com.google.android:flexbox library. Note the flexwrap and justifyContent property values. Then, set layout_wrapBefore = true on the view that you want to wrap the line of items before.

    <com.google.android.flexbox.FlexboxLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:flexWrap="wrap"
        app:justifyContent="center">
        
        <View ... />

        <View app:layout_wrapBefore="true" ... />

        <View ... />

    </com.google.android.flexbox.FlexboxLayout>

Use the gridLayoutManager = new GridLayoutManager(context,6) and override setSpanSizeLookup.

Example:

int totalSize=list.size();
gridLayoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
                    @Override
                    public int getSpanSize(int position) {
                        int span;
                        span = totalSize % 3;
                        if (totalSize < 3) {
                            return 6;
                        } else if (span == 0 || (position <= ((totalSize - 1) - span))) {
                            return 2;
                        } else if (span == 1) {
                            return 6;
                        } else {
                            return 3;
                        }
                    }
                });
         

This will work if you want to display 3 items in a row and remaining in the center of the grid.

Change the grid layout manager span counts accordingly your requirement.

you can use the new layoutManager from google [FlexLayoutManager][1] it will gives you a lot of control and flexibility over the recyclerView items

[1]: https://github.com/google/flexbox-layout "FlexLayoutManager"

you can add some layouts dynamically, for example:

• adapter object can be a horizontal LinearLayout

1- create a LinearLayout in java code and customize it (gravity,...)

2- add some icons to linearLayout

3- add linearLayout to your adapter

4- repeat 1,2,3

---

    // : declare new horizontal linearLayout
    ImageView myIcons[nomOfIcons];
    // : add all icons to myIcons
    for(int i=1; i<=nomOfIcons; i++){
        linearLayout.addView(myIcons[i - 1]);
        if(i%numOfIconsInOneHorizontalLinearLayout==0) {
            results.add(linearLayout); // add linearLayout to adapter dataSet
            // : declare new horizontal linearLayout
        }
    }
    if(n%numOfIconsInOneHorizontalLinearLayout!=0) // add last linearLayout if not added in the loop
        results.add(linearLayout);
    mAdapter.notifyDataSetChanged(); // update adapter

---

Currently, I think we need to write our own custom view for it because Android has not supported this feature as we expected yet.

It is the Sample I made in case someone needs it: https://github.com/mttdat/utils

(Try the CenterGridActivity.kt by adjusting Manifest file to start this activity as default)

Trust me, this gonna work. In your main xml file where you've put the recycler view, copy my code.

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="@dimen/_50sdp"
        android:gravity="center">

        <androidx.recyclerview.widget.RecyclerView
            android:layout_width="wrap_content"
            android:layout_height="@dimen/_50sdp"/>

    </LinearLayout>