In this tutorial, we will start another activity from an activity and finish it with transition animation.

What is Activity ? Activity Lifecycle Starting and Finishing Activities Animation Between Activity Transitions

1. What is Activity

If I give the definition of activity from developer.android.com :

“An Activity is an application component that provides a screen with which users can interact in order to do something, such as dial the phone, take a photo, send an email, or view a map.”

So, as I said before, you can assume activity as an application page-screen which is used by users to do somethings. But do not think that every different screen is an activity. We will see fragments in next lessons.

For example, in previous tutorials, Showing Toast on Button Click and Making Switch On/Off Button, every page is an activity.

How we define a class as an activity ? Open previous tutorials and see MainActivity.java classes. Those classes extends Activity. So this is how we do.

2. Activity Lifecycle

Every activity has a standart lifecycle. It starts, pauses, resumes, finishes…etc. with some spesific methods. Thanks to these methods, we can define somethings, do some configurations or release-destroy somethings at the right points. To sum up, we arrange how ui looks to users and decide reactions when users interact with ui ON THESE LIFECYCLE METHODS. Lets look what they are and when they active.

Below image is taken from here

So when an activity starts with onCreate() method. We can define, bind all view elements of layout and set some listeners to them in onCreate() scope.

Remember, in previous tutorials, we always do in this way.

What about other methods ? When an activity comes on device screen, respectively onCreate->onStart->onResume methods run and it becomes visible to user. When user press back button to close application , it follows onPause->onStop->onDestroy.

You can examine below to understand better.

Thats enough to go on our actual tutorial.

3. Starting and Finishing Activities

 Lets do something. Open an Android Studio project, if you forget how,follow this.

• We start with defining some resources which we will use.Add below string items to res/values/strings.xml
  
  <string name="main_activity_button_text">Start Second Activity</string> <string name="second_activity_button_text">Finish This Activity</string> <string name="main_activity_text">This is first activity</string> <string name="second_activity_text">This is second activity</string>

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  <string name="main_activity_button_text">Start Second Activity</string> <string name="second_activity_button_text">Finish This Activity</string> <string name="main_activity_text">This is first activity</string> <string name="second_activity_text">This is second activity</string>

  
  Add below color items to res/values/colors.xml
  
  <color name="main_activity_back_color">#deda78</color> <color name="second_activity_back_color">#de7878</color>

  1 2	<color name="main_activity_back_color">#deda78</color> <color name="second_activity_back_color">#de7878</color>

  
   
• Go on with designing our layout. Open your res/layout/activity_main.xml and write below code.
  
  Objective-C

  <?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" android:gravity="center" android:background="@color/main_activity_back_color"> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginLeft="20dp" android:layout_marginRight="20dp" android:gravity="center_horizontal" android:textSize="20sp" android:text="@string/main_activity_text"/> <Button android:id="@+id/main_activity_button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="10dp" android:padding="10dp" android:text="@string/main_activity_button_text"/> </LinearLayout>

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  <?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"     android:gravity="center"     android:background="@color/main_activity_back_color">       <TextView         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:layout_marginLeft="20dp"         android:layout_marginRight="20dp"         android:gravity="center_horizontal"         android:textSize="20sp"         android:text="@string/main_activity_text"/>       <Button         android:id="@+id/main_activity_button"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_marginTop="10dp"         android:padding="10dp"         android:text="@string/main_activity_button_text"/>   </LinearLayout>

  
   
• Above layout design contains a textview and button. You can check with switching to design mode.
  

 

 

• Our goal is starting another activity with clicking that button.
  Open your MainActivity class. Bind the button with its id and add a listener to detect click event.
  
  Java

  import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; public class MainActivity extends Activity { private Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //Bind button by id button=(Button)findViewById(R.id.main_activity_button); //Set a click listener to catch click on this button button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Call the function which starts second activity startSeconActivity(); } }); } private void startSeconActivity(){ } }

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  import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button;   public class MainActivity extends Activity {       private Button button;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);           //Bind button by id         button=(Button)findViewById(R.id.main_activity_button);           //Set a click listener to catch click on this button         button.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //Call the function which starts second activity                 startSeconActivity();             }         });     }       private void startSeconActivity(){            }   }

  
   
• This bring us to defining another activity. Click right on your package and create a class named SecondActivity

 

• Remember, there must be a layout file for an activity. So click right on your res/layout folder and create a layout file named activity_second

 

• Write below code to res/layout/activity_second.xml. This contains a textview and a button also. You can check switching to design mode.
  
  Objective-C

  <?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" android:gravity="center" android:background="@color/second_activity_back_color"> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginLeft="20dp" android:layout_marginRight="20dp" android:gravity="center_horizontal" android:textSize="20sp" android:text="@string/second_activity_text"/> <Button android:id="@+id/second_activity_button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="10dp" android:padding="10dp" android:text="@string/second_activity_button_text"/> </LinearLayout>

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  <?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"     android:gravity="center"     android:background="@color/second_activity_back_color">       <TextView         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:layout_marginLeft="20dp"         android:layout_marginRight="20dp"         android:gravity="center_horizontal"         android:textSize="20sp"         android:text="@string/second_activity_text"/>       <Button         android:id="@+id/second_activity_button"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_marginTop="10dp"         android:padding="10dp"         android:text="@string/second_activity_button_text"/>   </LinearLayout>

  
  

   

 

•  Our goal is finishing SecondActivity with clicking that button.
  Open your SecondActivity class and write below code.
  
  Java

  import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; public class SecondActivity extends Activity{ private Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_second); //Bind button by id button=(Button)findViewById(R.id.second_activity_button); //Set a click listener to catch click on this button button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Finish this activity here } }); } }

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  import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button;   public class SecondActivity extends Activity{       private Button button;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_second);           //Bind button by id         button=(Button)findViewById(R.id.second_activity_button);           //Set a click listener to catch click on this button         button.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //Finish this activity here             }         });     }   }

  
   

• So we have a SecondActivity now, it seems we need write the code which starts second activity from main activity but there is one important thing to do.
  

  Note If we create an activity, we need to declare it in AndroidManifest.xml. You can find it here. In AndroidManifest.xml , you need to find an activity declaration. (It doesnt have to be the same just pay attention <activity> …. </activity> tag). This activity declaration is for MainActivity Objective-C <activity android:name=".MainActivity" android:theme="@style/AppTheme"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> 1 2 3 4 5 6 7 8 <activity     android:name=".MainActivity"     android:theme="@style/AppTheme">     <intent-filter>         <action android:name="android.intent.action.MAIN" />         <category android:name="android.intent.category.LAUNCHER" />     </intent-filter> </activity> Declare SecondActivity below MainActivity declaration like this: Objective-C <activity android:name=".MainActivity" android:theme="@style/AppTheme"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".SecondActivity" android:theme="@style/AppTheme"> </activity> 1 2 3 4 5 6 7 8 9 10 11 12 <activity     android:name=".MainActivity"     android:theme="@style/AppTheme">     <intent-filter>         <action android:name="android.intent.action.MAIN" />         <category android:name="android.intent.category.LAUNCHER" />     </intent-filter> </activity> <activity     android:name=".SecondActivity"     android:theme="@style/AppTheme"> </activity> You can ask yourself that what <intent-filter> tag is. Android applications may have lots of activities. So the system needs to know which activity is the first activity which comes to screen when application starts. So <intent-filter></intent-filter> indicates the MainActivity as the first activity of application.

   

• Right now, we are ready to start SecondActivity. Open your MainActivity class and fill startSecondActivity() method like below. You need to Intent object to start SecondActivity.
  Java

  private void startSeconActivity(){ //Below code starts SecondActivity. //You need to create an intent to do this. Intent intent = new Intent(MainActivity.this,SecondActivity.class); startActivity(intent); }

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  private void startSeconActivity(){   //Below code starts SecondActivity.   //You need to create an intent to do this.   Intent intent = new Intent(MainActivity.this,SecondActivity.class);   startActivity(intent); }

   

• Run application and click button, see the SecondActivity begins.
• Next goal is finishing the SecondActivity and back to the MainActivity.
  Open your SecondActivity and fill the click listener scope of button like below.
  Java

  button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Call finish() method to finish second activity finish(); } });

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  button.setOnClickListener(new View.OnClickListener() {     @Override     public void onClick(View v) {         //Call finish() method to finish second activity         finish();     } });

   

• Run application again and start SecondActivity, then click button on SecondActivity and see it finishes. After finishing our MainActivity comes again.

 

4. Animation Between Activity Transitions

At this chapter, we will add an animation effect to activity transitions, forward and backward.

• We need to define animation resources and these resources must be at anim folder under res. So,click right on res and create a folder named anim.
  
  

 

• In anim folder, we create four different animation resources. Click right and create animation resource file four times.
  

 

• Animation resource files names is up to you. I choose below names.
  activity_enter_left_to_right.xml
  activity_enter_right_to_left.xml
  activity_exit_left_to_right.xml
  activity_exit_right_to_left.xml

 

• So anim folder should look after creatings.
  

 

• Write below codes for each animation resource.
  activity_enter_left_to_right
  
  Objective-C

  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android" android:fromXDelta="-100%" android:toXDelta="0%" android:duration="500"/>

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  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android"     android:fromXDelta="-100%"     android:toXDelta="0%"     android:duration="500"/>

  
  activity_enter_right_to_left
  
  Objective-C

  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android" android:fromXDelta="100%" android:toXDelta="0%" android:duration="500"/>

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  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android"     android:fromXDelta="100%"     android:toXDelta="0%"     android:duration="500"/>

  
  activity_exit_left_to_right
  
  Objective-C

  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android" android:fromXDelta="0%" android:toXDelta="100%" android:duration="500"/>

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  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android"     android:fromXDelta="0%"     android:toXDelta="100%"     android:duration="500"/>

  
  activity_exit_right_to_left
  
  Objective-C

  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android" android:fromXDelta="0%" android:toXDelta="-100%" android:duration="500"/>

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  <?xml version="1.0" encoding="utf-8"?> <translate xmlns:android="http://schemas.android.com/apk/res/android"     android:fromXDelta="0%"     android:toXDelta="-100%"     android:duration="500"/>

  
   
• Our animation resources are ready. Lets implement them on transitions.
  Open your SecondActivity and add overridePendingTransition method like below.
  
  Java

  import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; public class SecondActivity extends Activity{ private Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_second); //Define transition animation overridePendingTransition(R.anim.activity_enter_right_to_left, R.anim.activity_exit_right_to_left); //Bind button by id button=(Button)findViewById(R.id.second_activity_button); //Set a click listener to catch click on this button button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Call finish() method to finish second activity finish(); } }); } }

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  import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button;   public class SecondActivity extends Activity{       private Button button;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_second);           //Define transition animation         overridePendingTransition(R.anim.activity_enter_right_to_left, R.anim.activity_exit_right_to_left);           //Bind button by id         button=(Button)findViewById(R.id.second_activity_button);           //Set a click listener to catch click on this button         button.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //Call finish() method to finish second activity                 finish();             }         });     }   }

  
   
• Run application, start second activity clicking button and see translate animation from main activity to second activity.

 

• But when you press back button, there is no animation from second to main. We need to declare a translate animation also when main is back. Open your MainActivity and override onResume method like below.
  
  import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.Button; public class MainActivity extends Activity { private Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //Bind button by id button=(Button)findViewById(R.id.main_activity_button); //Set a click listener to catch click on this button button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //Call the function which starts second activity startSeconActivity(); } }); } @Override protected void onResume() { super.onResume(); //Define transition animation when this activity is back overridePendingTransition(R.anim.activity_enter_left_to_right, R.anim.activity_exit_left_to_right); } private void startSeconActivity(){ //Below code starts SecondActivity. //You need to create an intent to do this. Intent intent = new Intent(MainActivity.this,SecondActivity.class); startActivity(intent); } }

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  import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.Button;   public class MainActivity extends Activity {       private Button button;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);           //Bind button by id         button=(Button)findViewById(R.id.main_activity_button);           //Set a click listener to catch click on this button         button.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //Call the function which starts second activity                 startSeconActivity();             }         });     }       @Override     protected void onResume() {         super.onResume();         //Define transition animation when this activity is back         overridePendingTransition(R.anim.activity_enter_left_to_right, R.anim.activity_exit_left_to_right);     }       private void startSeconActivity(){         //Below code starts SecondActivity.         //You need to create an intent to do this.         Intent intent = new Intent(MainActivity.this,SecondActivity.class);         startActivity(intent);     }   }

  Note Remember above image of the activity lifecycle. When starting B activity from A activity, A activity paused. If B activity is finished, A activity comes to screen again with running its onResume method. At this point, we can declare an animation for transition B to A.

Run application and try forward backward animations. Thats all see you next tutorials.

Download Source Code If you don’t know how to open an existing Android Studio Project, follow this tutorial.