In Android, an activity is represent a single screen. Most applications have multiple activities to represent different screens, for example, one activity to display a list of the application settings, another activity to display the application status.
Note
Refer to this official Android activity article to understand more about Android activity.
In this tutorial, we show you how to interact with activity, when a button is clicked, navigate from current screen (current activity) to another screen (another activity).
1. XML Layouts
Create following two XML layout files in “res/layout/” folder :
res/layout/main.xml – Represent screen 1res/layout/main2.xml – Represent screen 2
File : res/layout/main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="I'm screen 1 (main.xml)"
android:textAppearance="?android:attr/textAppearanceLarge" />
<Button
android:id="@+id/button1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Click me to another screen" />
File : res/layout/main2.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="I'm screen 2 (main2.xml)"
android:textAppearance="?android:attr/textAppearanceLarge" />
2. Activities
Create two activity classes :
AppActivity.java –> main.xml
App2Activity.java –> main2.xml
To navigate from one screen to another screen, use following code :
Intent intent = new Intent(context, anotherActivity.class);
startActivity(intent);
File : AppActivity.java
package com.nadavatisiva.android;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.view.View;
import android.view.View.OnClickListener;
public class AppActivity extends Activity {
Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
addListenerOnButton();
}
public void addListenerOnButton() {
final Context context = this;
button = (Button) findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
Intent intent = new Intent(context, App2Activity.class);
startActivity(intent);
}
});
}
}
File : App2Activity.java
package com.nadavatisiva.android;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
public class App2Activity extends Activity {
Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main2);
}
}
3. AndroidManifest.xml
Declares above two activity classes in AndroidManifest.xml.
File : AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.nadavatisiva.android"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="10" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:label="@string/app_name"
android:name=".AppActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:label="@string/app_name"
android:name=".App2Activity" >
</activity>
</application>
</manifest>
4. Demo
Run application.
AppActivity.java (main.xml) screen is display.
When above button is clicked, it will navigate to another screen App2Activity.java (main2.xml)
If you have any doubts or suggestions, please place them in the comments.
Thanks happy coding :-)
