set left margin for view ... NullPointerException is coming

Question

my code This is an adapter and I want to align my layout dynamically to left and right in a list view...And null pointer exception is coming at relativeParams.leftMargin=80;

Java:

public View getView(int position, View view, ViewGroup parent)
    {
        ViewHolder viewHolder;
        ChatItem chatItem = getItem(position);
        viewAligned = view;
        if(view == null)
        {
            LayoutInflater layoutInflater = (LayoutInflater)  
            context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            view = layoutInflater.inflate(R.layout.cell_messages_layout, null);
            viewHolder = new ViewHolder();
            viewHolder.message = (TextView) view.findViewById(R.id.fromZoneMessage1);
            viewHolder.rl = (RelativeLayout) view.findViewById(R.id.messageLayout);
            view.setTag(viewHolder);
        }
        else
        {
            viewHolder = (ViewHolder) view.getTag();
        }

        viewHolder.message.setText(chatItem.getSenderMessage());
        if (chatItem.getAllignment() == 0)
        {
//          viewHolder.message.setGravity(Gravity.LEFT);
            viewHolder.message.setBackgroundResource(R.drawable.sent_message);
//          view.setBackgroundResource(R.drawable.sent_message);
        }
        else {
//          viewHolder.rl.setBackgroundResource(R.drawable.recieved_message);
//          view.holder.rl.set
//          viewHolder.message.setGravity(Gravity.RIGHT);
            viewHolder.message.setBackgroundResource(R.drawable.recieved_message);

            RelativeLayout.LayoutParams relativeParams = (RelativeLayout.LayoutParams) viewHolder.rl.getLayoutParams();
            relativeParams.leftMargin=80;
            viewHolder.rl.setLayoutParams(relativeParams);
//          LayoutParams lp = (LayoutParams) view.getLayoutParams();
        }
        return view;
    }

And my Layout is....

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/messageLayout" 
   >


    <TextView 
        android:id="@+id/fromZoneMessage1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#000000"
        android:textSize="20dp"
        android:textStyle="bold"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="5dp"
        android:layout_marginBottom="5dp"
        android:layout_marginRight="10dp"
        android:padding="5dp"
        android:text="Hey Jack"
        />

</RelativeLayout>

Please somebody help me to put left margin for my view....

In provided layout i am not able to locate `R.id.messageLayout` id for `RelativeLayout`. are you sure using right layout for ListView row view ? — ρяσѕρєя K, Jan 06 '15 at 10:06
Yeah, I'm sure Its relative layout for listView's row... is there any other way — V Jayakar Edidiah, Jan 06 '15 at 10:10
You `RelativeLayout` does not contain `id` attribute in XML. — Pratik Butani, Jan 06 '15 at 10:11
See the edited Question please..I forgot to provide you the latest one ... sorry... — V Jayakar Edidiah, Jan 06 '15 at 10:13
http://stackoverflow.com/questions/6025872/using-relativelayout-dynamically-and-setting-margins-in-px-dp-inch-mm — codePG, Jan 06 '15 at 11:56
Hey see the Fix I made in my answer...@codePG, ツ Fell in Love with Android ツ, ρяσѕρєя K — V Jayakar Edidiah, Jan 08 '15 at 12:00

score 1 · Accepted Answer · answered Jan 08 '15 at 11:58

I just type casted the view to Relative Layout and set its Gravity...For setting the parameters , means Margins I've taken another dummy Relative Layout inside of Main Relative layout and Adjusted it.

You can watch the below code and Relative layout

public View getView(int position, View view, ViewGroup parent)
    {
        ViewHolder viewHolder;
        ChatItem chatItem = getItem(position);
        viewAligned = view;
        if(view == null)
        {
            LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            view = layoutInflater.inflate(R.layout.cell_messages_layout, null);
            viewHolder = new ViewHolder();
            viewHolder.message = (TextView) view.findViewById(R.id.fromZoneMessage1);
            viewHolder.rl = (RelativeLayout) view.findViewById(R.id.messageLayout);
            view.setTag(viewHolder);
        }
        else
        {
            viewHolder = (ViewHolder) view.getTag();
        }

        viewHolder.message.setText(chatItem.getSenderMessage());
        if (chatItem.getAllignment() == 0)
        {

            viewHolder.message.setGravity(Gravity.LEFT);
            viewHolder.message.setBackgroundResource(R.drawable.recieved_message);
            ((RelativeLayout)view).setGravity(Gravity.RIGHT);
            android.widget.RelativeLayout.LayoutParams params = new LayoutParams(android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT, android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
            params.leftMargin = 50;
            viewHolder.rl.setLayoutParams(params);

                    }
        else {
            viewHolder.message.setGravity(Gravity.LEFT);
            viewHolder.message.setBackgroundResource(R.drawable.sent_message);
            ((RelativeLayout)view).setGravity(Gravity.LEFT);
            android.widget.RelativeLayout.LayoutParams params = new LayoutParams(android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT, android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
            params.rightMargin = 50;
            viewHolder.rl.setLayoutParams(params);
        }

        return view;
    }

Layout

<?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="wrap_content"
   >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/messageLayout" 
       >


    <TextView 
        android:id="@+id/fromZoneMessage1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#000000"
        android:textSize="20dp"
        android:textStyle="bold"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="5dp"
        android:layout_marginBottom="5dp"
        android:layout_marginRight="10dp"
        android:padding="5dp"
        android:text="Hey Jack"/>

</RelativeLayout>
</RelativeLayout>

score 0 · Answer 2 · answered Jan 06 '15 at 10:26

0

Instead of using RelativeLayout.LayoutParams try to use AbsListView.LayoutParams as your view is in ListView.

answered Jan 06 '15 at 10:26

Yogesh Narayanan

866
7
10

Not Working @Yogesh Narayanan – V Jayakar Edidiah Jan 06 '15 at 13:05
Yeah @Yogesh Narayanan – V Jayakar Edidiah Jan 06 '15 at 15:13
I think you can create new instance of layoutparams (do not use getLayoutParams() of rl) and set necessary alignments and assign it to rl. – Yogesh Narayanan Jan 06 '15 at 15:36
Did you fix the issue? – Yogesh Narayanan Jan 07 '15 at 04:53
Yeah After a lot of Struggle I fixed it ... You can see the below answer by me...@Yogesh Narayanan – V Jayakar Edidiah Jan 08 '15 at 11:59

set left margin for view ... NullPointerException is coming

2 Answers2