Design Chat Bubble UI in Android

    Instant Messaging is the familiar type of applications with us. They show each of our message in a bubble layout. It automatic change the dimension depend on message content size.
    In this post, I will provide a simple example that making this layout through using 9-patch images and ListView.

Designing bubble layout

    The "core design" is making the message bubble background with nine-patch images. So, firstly, you must prepare 2 bubble PNG images (for in and out messages).
     You can create the 9-patch images from them by using draw9patch tool in Android SDK. Let go to [YOUR_SDK_PATH]\sdk\tools folder and open Command Prompt (in Windows) or Terminal (in Mac, Linux) and type this command:
draw9patch
    You will see this dialog box:
    Dragging your bubble images to it, custom some details and saving it, you'll have new 9-patch images after done:
Out message background
In message background

Sample project code

    Put 2 9-patch images above to drawable folder and start coding!
    Design two layouts based on message type first:
item_chat_right.xml

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

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:background="@drawable/bubble_out"
        android:orientation="vertical"
        android:paddingBottom="10dp">

        <TextView
            android:id="@+id/txt_msg"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:maxWidth="100dp"
            android:padding="5dp"
            android:textColor="@android:color/holo_green_dark" />

    </LinearLayout>

</RelativeLayout>
item_chat_left.xml

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

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:background="@drawable/bubble_in"
        android:orientation="vertical"
        android:paddingBottom="10dp">

        <TextView
            android:id="@+id/txt_msg"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:maxWidth="100dp"
            android:padding="5dp"
            android:textColor="@android:color/holo_red_dark" />

    </LinearLayout>

</RelativeLayout>
    Create a POJO (chat message) for the project:
ChatMessage.java
package info.devexchanges.chatbubble;

public class ChatMessage {

    private String content;
    private boolean isMine;

    public ChatMessage(String content, boolean isMine) {
        this.content = content;
        this.isMine = isMine;
    }

    public String getContent() {
        return content;
    }

    public boolean isMine() {
        return isMine;
    }
}
    The nature of the chat messages list is ListView with odd/even row based on in or out message. Creating a ListView adapter with this design style, never forget to override getViewTypeCount() and getItemViewType() in code:
MessageAdapter.java
package info.devexchanges.chatbubble;

import android.app.Activity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

import java.util.List;

public class MessageAdapter extends ArrayAdapter<ChatMessage> {

    private Activity activity;
    private List<ChatMessage> messages;

    public MessageAdapter(Activity context, int resource, List<ChatMessage> objects) {
        super(context, resource, objects);
        this.activity = context;
        this.messages = objects;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        LayoutInflater inflater = (LayoutInflater) activity.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);

        int layoutResource = 0; // determined by view type
        ChatMessage chatMessage = getItem(position);
        int viewType = getItemViewType(position);

        if (chatMessage.isMine()) {
            layoutResource = R.layout.item_chat_left;
        } else {
            layoutResource = R.layout.item_chat_right;
        }

        if (convertView != null) {
            holder = (ViewHolder) convertView.getTag();
        } else {
            convertView = inflater.inflate(layoutResource, parent, false);
            holder = new ViewHolder(convertView);
            convertView.setTag(holder);
        }

        //set message content
        holder.msg.setText(chatMessage.getContent());

        return convertView;
    }

    @Override
    public int getViewTypeCount() {
        // return the total number of view types. this value should never change
        // at runtime
        return 2;
    }

    @Override
    public int getItemViewType(int position) {
        // return a value between 0 and (getViewTypeCount - 1)
        return position % 2;
    }

    private class ViewHolder {
        private TextView msg;

        public ViewHolder(View v) {
            msg = (TextView) v.findViewById(R.id.txt_msg);
        }
    }
}
    Simple Activity to run, there is no special point here:
MainActivity.java
package info.devexchanges.chatbubble;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private ListView listView;
    private View btnSend;
    private EditText editText;
    boolean isMine = true;
    private List<ChatMessage> chatMessages;
    private ArrayAdapter<ChatMessage> adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        chatMessages = new ArrayList<>();

        listView = (ListView) findViewById(R.id.list_msg);
        btnSend = findViewById(R.id.btn_chat_send);
        editText = (EditText) findViewById(R.id.msg_type);

        //set ListView adapter first
        adapter = new MessageAdapter(this, R.layout.item_chat_left, chatMessages);
        listView.setAdapter(adapter);

        //event for button SEND
        btnSend.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (editText.getText().toString().trim().equals("")) {
                    Toast.makeText(MainActivity.this, "Please input some text...", Toast.LENGTH_SHORT).show();
                } else {
                    //add message to list
                    ChatMessage chatMessage = new ChatMessage(editText.getText().toString(), isMine);
                    chatMessages.add(chatMessage);
                    adapter.notifyDataSetChanged();
                    editText.setText("");
                    if (isMine) {
                        isMine = false;
                    } else {
                        isMine = true;
                    }
                }
            }
        });
    }
}
    And it's layout:
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="@dimen/activity_horizontal_margin">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="0.9">

        <ListView
            android:id="@+id/list_msg"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginBottom="@dimen/activity_horizontal_margin"
            android:divider="@null"
            android:listSelector="@android:color/transparent"
            android:transcriptMode="alwaysScroll" />

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="0.1"
        android:orientation="horizontal">

        <EditText
            android:id="@+id/msg_type"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="0.7"
            android:hint="Input message" />

        <Button
            android:id="@+id/btn_chat_send"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="0.3"
            android:background="@color/background_floating_material_dark"
            android:text="Send"
            android:textColor="@color/background_material_light" />
    </LinearLayout>
</LinearLayout>
    Running application, you will have this result:

Conclusions

    Designing chatting bubble layout not as hard as you think. With the 9-patch images and the ListView widget, you can create the UI easily. Visit my @Github to get this full project code.
    Update: thank you, my all visitors! This is one of the most viewed posts on my blog. Some readers has asked me about making a "real" chat application, not only bubble UI. Please read my newer post about creating a simple chat app using Firebase to find out the solution!

Share


Previous post
« Prev Post
Next post
Next Post »