Tutorial of passing Strings or ArrayList or Arrays from one java file to another using Intents in Android..

Here I declared two java files in package and two xml files with respect to java files..

MainActivity.java:

package com.example.ex;
import java.util.ArrayList;
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;

public class MainActivity extends Activity {
/*ArrayList for Storing values*/
ArrayList ar=new ArrayList();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button b1=(Button) findViewById(R.id.button1);
/*inserting values into Arraylist*/
for(int i=0;i<10;i++)
{
/*add is method through which values are binded to ArrayList */
ar.add(i);
}
/*setting up OnClickListener and Passing values to Second.java file */
b1.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub

/*Declaring an Intent to Start another activity*/
Intent i=new Intent(MainActivity.this,Second.class);
/*putExtra() is method used to add some extra content to Intent variable..
* here as i am passing ArrayList i choose putStringArrayListExtra(),
* this method takes two parameters,first refers to key or id for ArrayList and
* Second is ArrayList name9It is similar for others also */
i.putStringArrayListExtra("key",ar);
/*now i am Starting activity Second */
startActivity(i);
}
});
}
}

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"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context=".MainActivity" >

    <Button

        android:id="@+id/button1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_marginLeft="38dp"

        android:layout_marginTop="152dp"

        android:text="@string/pas" />

</RelativeLayout>

Second.java:

package com.example.ex;

import java.util.ArrayList;

import android.app.Activity;

import android.os.Bundle;

import android.widget.ArrayAdapter;

import android.widget.ListView;

import android.widget.TextView;

public class Second extends Activity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.lay2);

ListView li=(ListView) findViewById(R.id.listView1);

/* Bundle for getting extras sent through Intent from MainActivity*/

Bundle b1=getIntent().getExtras();

/* ArrayList for Storing values which are sent from from MainActivty,

* getStringArrayList() will get values From Intent

* this method takes one parameter which is the first parameter of putStringArrayListExtra()*/

ArrayList s1=b1.getStringArrayList("key");

/*setting values of ArrayList to ListView */

li.setAdapter(new ArrayAdapter(Second.this,android.R.layout.simple_list_item_1,s1));

}

}

lay2.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" >

    <ListView

        android:id="@+id/listView1"

        android:layout_width="match_parent"

        android:layout_height="wrap_content" >

    </ListView>

</LinearLayout>

The output for the above Application is:

CHECK My Android APPS:
NCDupRemover-Backup,Clear all Contacts and Remove Duplicate Contacts..
NLauncherV2.2.2-Multipurpose Launcher
NLauncherCV0.2
NMemoV0.2

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