--- title: "Changing configuration at runtime" canonical_url: "https://www.nutrient.io/guides/android/customizing-the-interface/changing-configuration-at-runtime/" md_url: "https://www.nutrient.io/guides/android/customizing-the-interface/changing-configuration-at-runtime.md" last_updated: "2026-06-09T10:23:03.889Z" description: "You might want to change the configuration used to display your documents at runtime. This can easily be achieved when using PdfActivity or PdfFragment." --- You might want to change the configuration used to display your documents at runtime. This can easily be achieved when using `PdfActivity` or `PdfFragment`. Continue reading for instructions on how to change the configuration for each of these. ## Changing the configuration of the PdfActivity To change the configuration of the [`PdfActivity`](https://www.nutrient.io/api/android/nutrient/com.pspdfkit.ui/-pdf-activity/index.html), call [`PdfActivity#setConfiguration`](https://www.nutrient.io/api/android/nutrient/com.pspdfkit.ui/-pdf-activity/set-configuration.html), which will take care of saving the state and recreating the activity with the new configuration: ### DYNAMICCONFIGURATIONACTIVITY.KT ```kt class DynamicConfigurationActivity : PdfActivity() { override fun onPrepareOptionsMenu(menu: Menu): Boolean { super.onPrepareOptionsMenu(menu) menuInflater.inflate(R.menu.dynamic_configuration_menu, menu) return true } override fun onOptionsItemSelected(item: MenuItem): Boolean { var handled = false when (item.itemId) { R.id.toggle_scroll_direction -> { handled = true // Create the configuration builder with the configuration prefilled from the current configuration. val newConfiguration = PdfActivityConfiguration.Builder(configuration).scrollDirection( if (configuration.configuration.scrollDirection == PageScrollDirection.HORIZONTAL) PageScrollDirection.VERTICAL else PageScrollDirection.HORIZONTAL).build() // Set the configuration on the activity. This will recreate the activity, similar to changing the orientation or language. configuration = newConfiguration } } return handled || super.onOptionsItemSelected(item) } } ``` ### DYNAMICCONFIGURATIONACTIVITY.JAVA ```java public class DynamicConfigurationActivity extends PdfActivity { @Override public boolean onPrepareOptionsMenu(Menu menu) { super.onPrepareOptionsMenu(menu); getMenuInflater().inflate(R.menu.dynamic_configuration_menu, menu); return true; } @Override public boolean onOptionsItemSelected(@NonNull MenuItem item) { boolean handled = false; PdfActivityConfiguration configuration = getConfiguration(); switch (item.getItemId()) { case R.id.toggle_scroll_direction: { handled = true; // Create the configuration builder with the configuration prefilled from the current configuration. PdfActivityConfiguration newConfiguration = new PdfActivityConfiguration.Builder(getConfiguration()).scrollDirection( configuration.getConfiguration().getScrollDirection() == PageScrollDirection.HORIZONTAL? PageScrollDirection.VERTICAL : PageScrollDirection.HORIZONTAL).build(); // Set the configuration on the activity. This will recreate the activity, similar to changing the orientation or language. setConfiguration(newConfiguration); break; } } return handled || super.onOptionsItemSelected(item); } } ``` If you want to change the configuration immediately after the activity is opened, we recommend doing it before `onCreate()`. In this case, we won’t restart the current activity, thereby making the configuration change much quicker: ### STARTUPCONFIGURATIONCHANGEACTIVITY.KT ```kt class StartupConfigurationChangeActivity : PdfActivity() { override fun onCreate(savedInstanceState: Bundle) { val newConfiguration = PdfActivityConfiguration.Builder(configuration) // Change your configuration.....build() // Set the new configuration. this.configuration = newConfiguration // Make sure to call `super.onCreate()` on the parent `PdfActivity`. super.onCreate(savedInstanceState) } } ``` ### STARTUPCONFIGURATIONCHANGEACTIVITY.JAVA ```java public class StartupConfigurationChangeActivity extends PdfActivity { @Override protected void onCreate(Bundle savedInstanceState) { PdfActivityConfigurations newConfiguration = PdfActivityConfiguration.Builder(configuration) // Change your configuration.....build(); // Set the new configuration. setConfiguration(newConfiguration); // Make sure to call `super.onCreate()` on the parent `PdfActivity`. super.onCreate(savedInstanceState); } } ``` ## Changing the configuration of the PdfFragment To change the configuration of the [`PdfFragment`](https://www.nutrient.io/api/android/nutrient/com.pspdfkit.ui/-pdf-fragment/index.html), you need to: 1. Save the state of your current fragment using [`PdfFragment#getState`](https://www.nutrient.io/api/android/nutrient/com.pspdfkit.ui/-pdf-fragment/get-state.html). 2. Create a new fragment with the desired configuration using [`PdfFragment#newInstance`](https://www.nutrient.io/api/android/nutrient/com.pspdfkit.ui/-pdf-fragment/new-instance.html). 3. Replace the original fragment with the new one. 4. Restore the state using [`PdfFragment#setState`](https://www.nutrient.io/api/android/nutrient/com.pspdfkit.ui/-pdf-fragment/set-state.html). ### KOTLIN ```kotlin /** The currently displayed `PdfFragment`. **/ private var fragment: PdfFragment? = null set(fragment) { // Remove the previous fragment. this.fragment?.let { it.removeDocumentListener(this) } field = fragment if (fragment!= null) { // Replace the old fragment with a new one. supportFragmentManager.beginTransaction().replace(R.id.fragmentContainer, fragment).commit() // Register the activity to be notified when the document is loaded. fragment.addDocumentListener(this) } } /** Switches between horizontal and vertical scrolling. */ private fun toggleScrollDirection() { val currentFragment = fragment val currentDocument = fragment?.document if (currentFragment == null || currentDocument == null || currentFragment.configuration == null) return val scrollDirection = currentFragment.configuration.scrollDirection // Copy the existing configuration to a new configuration builder. val configurationBuilder = PdfConfiguration.Builder(currentFragment.configuration) // Toggle the scroll direction. configurationBuilder.scrollDirection( if (scrollDirection == PageScrollDirection.HORIZONTAL) PageScrollDirection.VERTICAL else PageScrollDirection.HORIZONTAL) // Save the old fragment state. val state = currentFragment.state // Create the fragment with the already loaded document and the new configuration. val newFragment = PdfFragment.newInstance(currentDocument, configurationBuilder.build()) fragment = newFragment // Restore the fragment state. newFragment.state = state } ``` ### JAVA ```java /** The currently displayed `PdfFragment`. **/ private PdfFragment fragment; /** Replaces the currently displayed fragment. */ private void setFragment(@NonNull PdfFragment fragment) { // Remove the previous fragment. if (this.fragment!= null) { this.fragment.removeDocumentListener(this); } this.fragment = fragment; // Replace the old fragment with a new one. getSupportFragmentManager().beginTransaction().replace(R.id.fragmentContainer, fragment).commit(); // Register the activity to be notified when the document is loaded. fragment.addDocumentListener(this); } /** Switches between horizontal and vertical scrolling. */ private void toggleScrollDirection() { if (fragment == null || fragment.getDocument() == null || fragment.getConfiguration() == null) return; PageScrollDirection scrollDirection = fragment.getConfiguration().getScrollDirection(); // Copy the existing configuration to a new configuration builder. PdfConfiguration.Builder configurationBuilder = new PdfConfiguration.Builder(fragment.getConfiguration()); // Toggle the scroll direction. configurationBuilder.scrollDirection( scrollDirection == PageScrollDirection.HORIZONTAL? PageScrollDirection.VERTICAL : PageScrollDirection.HORIZONTAL); // Save the old fragment state. Bundle state = fragment.getState(); // Create the fragment with the already loaded document and the new configuration. PdfFragment newFragment = PdfFragment.newInstance(fragment.getDocument(), configurationBuilder.build()); setFragment(newFragment); // Restore the fragment state. newFragment.setState(state); } ``` For more details, you can check out `DynamicConfigurationExample` and `CustomFragmentDynamicConfigurationExample` in the Catalog app. --- ## Related pages - [Text Markup Annotations](/guides/android/annotations/text-markup-annotations.md) - [Document Sharing](/guides/android/miscellaneous/document-sharing.md) - [Retrieving Highlighted Text](/guides/android/prebuilt-solutions/common-use-cases/retrieving-highlighted-text.md) - [Document Title Styling](/guides/android/prebuilt-solutions/common-use-cases/document-title-styling.md)