Intent Example

An Android application can contain zero or more activities. When your application has more than one activity, you may need to navigate from one activity to another. In Android, you navigate between activities through what is known as an intent.

In this tutorial we will show how to pass a message using Intents :

File : res/layout/activity_main.xml

<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"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="24dp"
        android:text="Intent Example"
        android:textAppearance="?android:attr/textAppearanceMedium" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="50dp"
        android:ems="10" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="26dp"
        android:text="Send" />


</RelativeLayout>

File : res/layout/next_activity.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" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="29dp"
        android:layout_marginTop="32dp"
        android:textAppearance="?android:attr/textAppearanceLarge" />


</RelativeLayout>


File : MainActivity.java

package com.example.intent_example;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends Activity {

private Button Submit;
private EditText Value;
public String message;
public final static String EXTRA_MESSAGE = "com.example.intent_example.MESSAGE";

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

this.Submit = (Button) findViewById(R.id.button1);
this.Value = (EditText) findViewById(R.id.editText1);

this.Submit.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
sendMessage(v);
}
});
}

/** Called when the user clicks the Send button */
public void sendMessage(View view) {
// Do something in response to button
message = Value.getText().toString();
Intent intent = new Intent(MainActivity.this,
DisplayMessageActivity.class);
intent.putExtra(EXTRA_MESSAGE, message);
   startActivity(intent);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}


}

File : DisplayMessageActivity.java


package com.example.intent_example;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

public class DisplayMessageActivity extends Activity {

private TextView display_msg;

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

this.display_msg = (TextView) findViewById(R.id.textView1);

// Get the message from the intent
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);

this.display_msg.setText(message);

}

}


Add this code snippet to AndroidManifest.xml file : 

<activity  android:name=".DisplayMessageActivity"

              android:label="Display Message"> </activity>



Output :