PlatformChannel.java

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// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
 
package io.flutter.embedding.engine.systemchannels;
 
import android.content.pm.ActivityInfo;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.VisibleForTesting;
import io.flutter.Log;
import io.flutter.embedding.engine.dart.DartExecutor;
import io.flutter.plugin.common.JSONMethodCodec;
import io.flutter.plugin.common.MethodCall;
import io.flutter.plugin.common.MethodChannel;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
 
/**
 * System channel that receives requests for host platform behavior, e.g., haptic and sound effects,
 * system chrome configurations, and clipboard interaction.
 */
public class PlatformChannel {
  private static final String TAG = "PlatformChannel";
 
  @NonNull public final MethodChannel channel;
  @Nullable private PlatformMessageHandler platformMessageHandler;
 
  @NonNull @VisibleForTesting
  final MethodChannel.MethodCallHandler parsingMethodCallHandler =
      new MethodChannel.MethodCallHandler() {
        @Override
        public void onMethodCall(@NonNull MethodCall call, @NonNull MethodChannel.Result result) {
          if (platformMessageHandler == null) {
            // If no explicit PlatformMessageHandler has been registered then we don't
            // need to forward this call to an API. Return.
            return;
          }
 
          String method = call.method;
          Object arguments = call.arguments;
          Log.v(TAG, "Received '" + method + "' message.");
          try {
            switch (method) {
              case "SystemSound.play":
                try {
                  SoundType soundType = SoundType.fromValue((String) arguments);
                  platformMessageHandler.playSystemSound(soundType);
                  result.success(null);
                } catch (NoSuchFieldException exception) {
                  // The desired sound type does not exist.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "HapticFeedback.vibrate":
                try {
                  HapticFeedbackType feedbackType =
                      HapticFeedbackType.fromValue((String) arguments);
                  platformMessageHandler.vibrateHapticFeedback(feedbackType);
                  result.success(null);
                } catch (NoSuchFieldException exception) {
                  // The desired feedback type does not exist.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "SystemChrome.setPreferredOrientations":
                try {
                  int androidOrientation = decodeOrientations((JSONArray) arguments);
                  platformMessageHandler.setPreferredOrientations(androidOrientation);
                  result.success(null);
                } catch (JSONException | NoSuchFieldException exception) {
                  // JSONException: One or more expected fields were either omitted or referenced an
                  // invalid type.
                  // NoSuchFieldException: One or more expected fields were either omitted or
                  // referenced an invalid type.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "SystemChrome.setApplicationSwitcherDescription":
                try {
                  AppSwitcherDescription description =
                      decodeAppSwitcherDescription((JSONObject) arguments);
                  platformMessageHandler.setApplicationSwitcherDescription(description);
                  result.success(null);
                } catch (JSONException exception) {
                  // One or more expected fields were either omitted or referenced an invalid type.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "SystemChrome.setEnabledSystemUIOverlays":
                try {
                  List<SystemUiOverlay> overlays = decodeSystemUiOverlays((JSONArray) arguments);
                  platformMessageHandler.showSystemOverlays(overlays);
                  result.success(null);
                } catch (JSONException | NoSuchFieldException exception) {
                  // JSONException: One or more expected fields were either omitted or referenced an
                  // invalid type.
                  // NoSuchFieldException: One or more of the overlay names are invalid.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "SystemChrome.setEnabledSystemUIMode":
                try {
                  SystemUiMode mode = decodeSystemUiMode((String) arguments);
                  platformMessageHandler.showSystemUiMode(mode);
                  result.success(null);
                } catch (JSONException | NoSuchFieldException exception) {
                  // JSONException: One or more expected fields were either omitted or referenced an
                  // invalid type.
                  // NoSuchFieldException: One or more of the overlay names are invalid.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "SystemChrome.setSystemUIChangeListener":
                platformMessageHandler.setSystemUiChangeListener();
                result.success(null);
                break;
              case "SystemChrome.restoreSystemUIOverlays":
                platformMessageHandler.restoreSystemUiOverlays();
                result.success(null);
                break;
              case "SystemChrome.setSystemUIOverlayStyle":
                try {
                  SystemChromeStyle systemChromeStyle =
                      decodeSystemChromeStyle((JSONObject) arguments);
                  platformMessageHandler.setSystemUiOverlayStyle(systemChromeStyle);
                  result.success(null);
                } catch (JSONException | NoSuchFieldException exception) {
                  // JSONException: One or more expected fields were either omitted or referenced an
                  // invalid type.
                  // NoSuchFieldException: One or more of the brightness names are invalid.
                  result.error("error", exception.getMessage(), null);
                }
                break;
              case "SystemNavigator.setFrameworkHandlesBack":
                {
                  boolean frameworkHandlesBack = (boolean) arguments;
                  platformMessageHandler.setFrameworkHandlesBack(frameworkHandlesBack);
                  result.success(null);
                  break;
                }
              case "SystemNavigator.pop":
                platformMessageHandler.popSystemNavigator();
                result.success(null);
                break;
              case "Clipboard.getData":
                {
                  String contentFormatName = (String) arguments;
                  ClipboardContentFormat clipboardFormat = null;
                  if (contentFormatName != null) {
                    try {
                      clipboardFormat = ClipboardContentFormat.fromValue(contentFormatName);
                    } catch (NoSuchFieldException exception) {
                      // An unsupported content format was requested. Return failure.
                      result.error(
                          "error", "No such clipboard content format: " + contentFormatName, null);
                    }
                  }
 
                  CharSequence clipboardContent =
                      platformMessageHandler.getClipboardData(clipboardFormat);
                  if (clipboardContent != null) {
                    JSONObject response = new JSONObject();
                    response.put("text", clipboardContent);
                    result.success(response);
                  } else {
                    result.success(null);
                  }
                  break;
                }
              case "Clipboard.setData":
                {
                  String clipboardContent = ((JSONObject) arguments).getString("text");
                  platformMessageHandler.setClipboardData(clipboardContent);
                  result.success(null);
                  break;
                }
              case "Clipboard.hasStrings":
                {
                  boolean hasStrings = platformMessageHandler.clipboardHasStrings();
                  JSONObject response = new JSONObject();
                  response.put("value", hasStrings);
                  result.success(response);
                  break;
                }
              case "Share.invoke":
                String text = (String) arguments;
                platformMessageHandler.share(text);
                result.success(null);
                break;
              default:
                result.notImplemented();
                break;
            }
          } catch (JSONException e) {
            result.error("error", "JSON error: " + e.getMessage(), null);
          }
        }
      };
 
  /**
   * Constructs a {@code PlatformChannel} that connects Android to the Dart code running in {@code
   * dartExecutor}.
   *
   * <p>The given {@code dartExecutor} is permitted to be idle or executing code.
   *
   * <p>See {@link DartExecutor}.
   */
  public PlatformChannel(@NonNull DartExecutor dartExecutor) {
    channel = new MethodChannel(dartExecutor, "flutter/platform", JSONMethodCodec.INSTANCE);
    channel.setMethodCallHandler(parsingMethodCallHandler);
  }
 
  /**
   * Sets the {@link PlatformMessageHandler} which receives all events and requests that are parsed
   * from the underlying platform channel.
   */
  public void setPlatformMessageHandler(@Nullable PlatformMessageHandler platformMessageHandler) {
    this.platformMessageHandler = platformMessageHandler;
  }
 
  /** Informs Flutter of a change in the SystemUI overlays. */
  public void systemChromeChanged(boolean overlaysAreVisible) {
    Log.v(TAG, "Sending 'systemUIChange' message.");
    channel.invokeMethod("SystemChrome.systemUIChange", Arrays.asList(overlaysAreVisible));
  }
 
  // TODO(mattcarroll): add support for IntDef annotations, then add @ScreenOrientation
 
  /**
   * Decodes a series of orientations to an aggregate desired orientation.
   *
   * @throws JSONException if {@code encodedOrientations} does not contain expected keys and value
   *     types.
   * @throws NoSuchFieldException if any given encoded orientation is not a valid orientation name.
   */
  private int decodeOrientations(@NonNull JSONArray encodedOrientations)
      throws JSONException, NoSuchFieldException {
    int requestedOrientation = 0x00;
    int firstRequestedOrientation = 0x00;
    for (int index = 0; index < encodedOrientations.length(); index += 1) {
      String encodedOrientation = encodedOrientations.getString(index);
      DeviceOrientation orientation = DeviceOrientation.fromValue(encodedOrientation);
 
      switch (orientation) {
        case PORTRAIT_UP:
          requestedOrientation |= 0x01;
          break;
        case PORTRAIT_DOWN:
          requestedOrientation |= 0x04;
          break;
        case LANDSCAPE_LEFT:
          requestedOrientation |= 0x02;
          break;
        case LANDSCAPE_RIGHT:
          requestedOrientation |= 0x08;
          break;
      }
 
      if (firstRequestedOrientation == 0x00) {
        firstRequestedOrientation = requestedOrientation;
      }
    }
 
    switch (requestedOrientation) {
      case 0x00:
        return ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
      case 0x01:
        return ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
      case 0x02:
        return ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
      case 0x04:
        return ActivityInfo.SCREEN_ORIENTATION_REVERSE_PORTRAIT;
      case 0x05:
        return ActivityInfo.SCREEN_ORIENTATION_USER_PORTRAIT;
      case 0x08:
        return ActivityInfo.SCREEN_ORIENTATION_REVERSE_LANDSCAPE;
      case 0x0a:
        return ActivityInfo.SCREEN_ORIENTATION_USER_LANDSCAPE;
      case 0x0b:
        return ActivityInfo.SCREEN_ORIENTATION_USER;
      case 0x0f:
        return ActivityInfo.SCREEN_ORIENTATION_FULL_USER;
      case 0x03: // portraitUp and landscapeLeft
      case 0x06: // portraitDown and landscapeLeft
      case 0x07: // portraitUp, portraitDown, and landscapeLeft
      case 0x09: // portraitUp and landscapeRight
      case 0x0c: // portraitDown and landscapeRight
      case 0x0d: // portraitUp, portraitDown, and landscapeRight
      case 0x0e: // portraitDown, landscapeLeft, and landscapeRight
        // Android can't describe these cases, so just default to whatever the first
        // specified value was.
        switch (firstRequestedOrientation) {
          case 0x01:
            return ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
          case 0x02:
            return ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
          case 0x04:
            return ActivityInfo.SCREEN_ORIENTATION_REVERSE_PORTRAIT;
          case 0x08:
            return ActivityInfo.SCREEN_ORIENTATION_REVERSE_LANDSCAPE;
        }
    }
 
    // Execution should never get this far, but if it does then we default
    // to a portrait orientation.
    return ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
  }
 
  @NonNull
  private AppSwitcherDescription decodeAppSwitcherDescription(
      @NonNull JSONObject encodedDescription) throws JSONException {
    int color = encodedDescription.getInt("primaryColor");
    if (color != 0) { // 0 means color isn't set, use system default
      color = color | 0xFF000000; // color must be opaque if set
    }
    String label = encodedDescription.getString("label");
    return new AppSwitcherDescription(color, label);
  }
 
  /**
   * Decodes a list of JSON-encoded overlays to a list of {@link SystemUiOverlay}.
   *
   * @throws JSONException if {@code encodedSystemUiOverlay} does not contain expected keys and
   *     value types.
   * @throws NoSuchFieldException if any of the given encoded overlay names are invalid.
   */
  @NonNull
  private List<SystemUiOverlay> decodeSystemUiOverlays(@NonNull JSONArray encodedSystemUiOverlay)
      throws JSONException, NoSuchFieldException {
    List<SystemUiOverlay> overlays = new ArrayList<>();
    for (int i = 0; i < encodedSystemUiOverlay.length(); ++i) {
      String encodedOverlay = encodedSystemUiOverlay.getString(i);
      SystemUiOverlay overlay = SystemUiOverlay.fromValue(encodedOverlay);
      switch (overlay) {
        case TOP_OVERLAYS:
          overlays.add(SystemUiOverlay.TOP_OVERLAYS);
          break;
        case BOTTOM_OVERLAYS:
          overlays.add(SystemUiOverlay.BOTTOM_OVERLAYS);
          break;
      }
    }
    return overlays;
  }
 
  /**
   * Decodes an object of JSON-encoded mode to a {@link SystemUiMode}.
   *
   * @throws JSONException if {@code encodedSystemUiMode} does not contain expected keys and value
   *     types.
   * @throws NoSuchFieldException if any of the given encoded mode name is invalid.
   */
  @NonNull
  private SystemUiMode decodeSystemUiMode(@NonNull String encodedSystemUiMode)
      throws JSONException, NoSuchFieldException {
    SystemUiMode mode = SystemUiMode.fromValue(encodedSystemUiMode);
    switch (mode) {
      case LEAN_BACK:
        return SystemUiMode.LEAN_BACK;
      case IMMERSIVE:
        return SystemUiMode.IMMERSIVE;
      case IMMERSIVE_STICKY:
        return SystemUiMode.IMMERSIVE_STICKY;
      case EDGE_TO_EDGE:
        return SystemUiMode.EDGE_TO_EDGE;
    }
 
    // Execution should never ever get this far, but if it does, we default to edge to edge.
    return SystemUiMode.EDGE_TO_EDGE;
  }
 
  /**
   * Decodes a JSON-encoded {@code encodedStyle} to a {@link SystemChromeStyle}.
   *
   * @throws JSONException if {@code encodedStyle} does not contain expected keys and value types.
   * @throws NoSuchFieldException if any provided brightness name is invalid.
   */
  @NonNull
  private SystemChromeStyle decodeSystemChromeStyle(@NonNull JSONObject encodedStyle)
      throws JSONException, NoSuchFieldException {
    // TODO(mattcarroll): add color annotation
    Integer statusBarColor = null;
    Brightness statusBarIconBrightness = null;
    Boolean systemStatusBarContrastEnforced = null;
    // TODO(mattcarroll): add color annotation
    Integer systemNavigationBarColor = null;
    Brightness systemNavigationBarIconBrightness = null;
    // TODO(mattcarroll): add color annotation
    Integer systemNavigationBarDividerColor = null;
    Boolean systemNavigationBarContrastEnforced = null;
 
    if (!encodedStyle.isNull("statusBarColor")) {
      statusBarColor = encodedStyle.getInt("statusBarColor");
    }
 
    if (!encodedStyle.isNull("statusBarIconBrightness")) {
      statusBarIconBrightness =
          Brightness.fromValue(encodedStyle.getString("statusBarIconBrightness"));
    }
 
    if (!encodedStyle.isNull("systemStatusBarContrastEnforced")) {
      systemStatusBarContrastEnforced = encodedStyle.getBoolean("systemStatusBarContrastEnforced");
    }
 
    if (!encodedStyle.isNull("systemNavigationBarColor")) {
      systemNavigationBarColor = encodedStyle.getInt("systemNavigationBarColor");
    }
 
    if (!encodedStyle.isNull("systemNavigationBarIconBrightness")) {
      systemNavigationBarIconBrightness =
          Brightness.fromValue(encodedStyle.getString("systemNavigationBarIconBrightness"));
    }
 
    if (!encodedStyle.isNull("systemNavigationBarDividerColor")) {
      systemNavigationBarDividerColor = encodedStyle.getInt("systemNavigationBarDividerColor");
    }
 
    if (!encodedStyle.isNull("systemNavigationBarContrastEnforced")) {
      systemNavigationBarContrastEnforced =
          encodedStyle.getBoolean("systemNavigationBarContrastEnforced");
    }
 
    return new SystemChromeStyle(
        statusBarColor,
        statusBarIconBrightness,
        systemStatusBarContrastEnforced,
        systemNavigationBarColor,
        systemNavigationBarIconBrightness,
        systemNavigationBarDividerColor,
        systemNavigationBarContrastEnforced);
  }
 
  /**
   * Handler that receives platform messages sent from Flutter to Android through a given {@link
   * PlatformChannel}.
   *
   * <p>To register a {@code PlatformMessageHandler} with a {@link PlatformChannel}, see {@link
   * PlatformChannel#setPlatformMessageHandler(PlatformMessageHandler)}.
   */
  public interface PlatformMessageHandler {
    /** The Flutter application would like to play the given {@code soundType}. */
    void playSystemSound(@NonNull SoundType soundType);
 
    /** The Flutter application would like to play the given haptic {@code feedbackType}. */
    void vibrateHapticFeedback(@NonNull HapticFeedbackType feedbackType);
 
    /** The Flutter application would like to display in the given {@code androidOrientation}. */
    // TODO(mattcarroll): add @ScreenOrientation annotation
    void setPreferredOrientations(int androidOrientation);
 
    /**
     * The Flutter application would like to be displayed in Android's app switcher with the visual
     * representation described in the given {@code description}.
     *
     * <p>See the related Android documentation:
     * https://developer.android.com/guide/components/activities/recents
     */
    void setApplicationSwitcherDescription(@NonNull AppSwitcherDescription description);
 
    /**
     * The Flutter application would like the Android system to display the given {@code overlays}.
     *
     * <p>{@link SystemUiOverlay#TOP_OVERLAYS} refers to system overlays such as the status bar,
     * while {@link SystemUiOverlay#BOTTOM_OVERLAYS} refers to system overlays such as the
     * back/home/recents navigation on the bottom of the screen.
     *
     * <p>An empty list of {@code overlays} should hide all system overlays.
     */
    void showSystemOverlays(@NonNull List<SystemUiOverlay> overlays);
 
    /**
     * The Flutter application would like the Android system to display the given {@code mode}.
     *
     * <p>{@link SystemUiMode#LEAN_BACK} refers to a fullscreen experience that restores system bars
     * upon tapping anywhere in the application. This tap gesture is not received by the
     * application.
     *
     * <p>{@link SystemUiMode#IMMERSIVE} refers to a fullscreen experience that restores system bars
     * upon swiping from the edge of the viewport. This swipe gesture is not recived by the
     * application.
     *
     * <p>{@link SystemUiMode#IMMERSIVE_STICKY} refers to a fullscreen experience that restores
     * system bars upon swiping from the edge of the viewport. This swipe gesture is received by the
     * application, in contrast to {@link SystemUiMode#IMMERSIVE}.
     *
     * <p>{@link SystemUiMode#EDGE_TO_EDGE} refers to a layout configuration that will consume the
     * full viewport. This full screen experience does not hide status bars. These status bars can
     * be set to transparent, making the buttons and icons hover over the fullscreen application.
     */
    void showSystemUiMode(@NonNull SystemUiMode mode);
 
    /**
     * The Flutter application would like the Android system to notify the framework when the system
     * ui visibility has changed.
     *
     * <p>This is relevant when using {@link SystemUiMode}s for fullscreen applications, from which
     * the system overlays can appear or disappear based on user input.
     */
    void setSystemUiChangeListener();
 
    /**
     * The Flutter application would like to restore the visibility of system overlays to the last
     * set of overlays sent via {@link #showSystemOverlays(List)} or {@link
     * #showSystemUiMode(SystemUiMode)}.
     *
     * <p>If {@link #showSystemOverlays(List)} or {@link #showSystemUiMode(SystemUiMode)} has yet to
     * be called, then a default system overlay appearance is desired:
     *
     * <p>{@code View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN }
     */
    void restoreSystemUiOverlays();
 
    /**
     * The Flutter application would like the system chrome to present itself with the given {@code
     * systemUiOverlayStyle}, i.e., the given status bar and navigation bar colors and brightness.
     */
    void setSystemUiOverlayStyle(@NonNull SystemChromeStyle systemUiOverlayStyle);
 
    /**
     * The Flutter application would or would not like to handle navigation pop events itself.
     *
     * <p>Relevant for registering and unregistering the app's OnBackInvokedCallback for the
     * Predictive Back feature, for example as in {@link
     * io.flutter.embedding.android.FlutterActivity}.
     */
    default void setFrameworkHandlesBack(boolean frameworkHandlesBack) {}
 
    /**
     * The Flutter application would like to pop the top item off of the Android app's navigation
     * back stack.
     */
    void popSystemNavigator();
 
    /**
     * The Flutter application would like to receive the current data in the clipboard and have it
     * returned in the given {@code format}.
     */
    @Nullable
    CharSequence getClipboardData(@Nullable ClipboardContentFormat format);
 
    /**
     * The Flutter application would like to set the current data in the clipboard to the given
     * {@code text}.
     */
    void setClipboardData(@NonNull String text);
 
    /**
     * The Flutter application would like to know if the clipboard currently contains a string that
     * can be pasted.
     */
    boolean clipboardHasStrings();
 
    /**
     * The Flutter application would like to share the given {@code text} using the Android standard
     * intent action named {@code Intent.ACTION_SEND}. See:
     * https://developer.android.com/reference/android/content/Intent.html#ACTION_SEND
     */
    void share(@NonNull String text);
  }
 
  /** Types of sounds the Android OS can play on behalf of an application. */
  public enum SoundType {
    CLICK("SystemSoundType.click"),
    ALERT("SystemSoundType.alert");
 
    @NonNull
    static SoundType fromValue(@NonNull String encodedName) throws NoSuchFieldException {
      for (SoundType soundType : SoundType.values()) {
        if (soundType.encodedName.equals(encodedName)) {
          return soundType;
        }
      }
      throw new NoSuchFieldException("No such SoundType: " + encodedName);
    }
 
    @NonNull private final String encodedName;
 
    SoundType(@NonNull String encodedName) {
      this.encodedName = encodedName;
    }
  }
 
  /** The types of haptic feedback that the Android OS can generate on behalf of an application. */
  public enum HapticFeedbackType {
    STANDARD(null),
    LIGHT_IMPACT("HapticFeedbackType.lightImpact"),
    MEDIUM_IMPACT("HapticFeedbackType.mediumImpact"),
    HEAVY_IMPACT("HapticFeedbackType.heavyImpact"),
    SELECTION_CLICK("HapticFeedbackType.selectionClick");
 
    @NonNull
    static HapticFeedbackType fromValue(@Nullable String encodedName) throws NoSuchFieldException {
      for (HapticFeedbackType feedbackType : HapticFeedbackType.values()) {
        if ((feedbackType.encodedName == null && encodedName == null)
            || (feedbackType.encodedName != null && feedbackType.encodedName.equals(encodedName))) {
          return feedbackType;
        }
      }
      throw new NoSuchFieldException("No such HapticFeedbackType: " + encodedName);
    }
 
    @Nullable private final String encodedName;
 
    HapticFeedbackType(@Nullable String encodedName) {
      this.encodedName = encodedName;
    }
  }
 
  /** The possible desired orientations of a Flutter application. */
  public enum DeviceOrientation {
    PORTRAIT_UP("DeviceOrientation.portraitUp"),
    PORTRAIT_DOWN("DeviceOrientation.portraitDown"),
    LANDSCAPE_LEFT("DeviceOrientation.landscapeLeft"),
    LANDSCAPE_RIGHT("DeviceOrientation.landscapeRight");
 
    @NonNull
    static DeviceOrientation fromValue(@NonNull String encodedName) throws NoSuchFieldException {
      for (DeviceOrientation orientation : DeviceOrientation.values()) {
        if (orientation.encodedName.equals(encodedName)) {
          return orientation;
        }
      }
      throw new NoSuchFieldException("No such DeviceOrientation: " + encodedName);
    }
 
    @NonNull private String encodedName;
 
    DeviceOrientation(@NonNull String encodedName) {
      this.encodedName = encodedName;
    }
  }
 
  /**
   * The set of Android system UI overlays as perceived by the Flutter application.
   *
   * <p>Android includes many more overlay options and flags than what is provided by {@code
   * SystemUiOverlay}. Flutter only requires control over a subset of the overlays and those
   * overlays are represented by {@code SystemUiOverlay} values.
   */
  public enum SystemUiOverlay {
    TOP_OVERLAYS("SystemUiOverlay.top"),
    BOTTOM_OVERLAYS("SystemUiOverlay.bottom");
 
    @NonNull
    static SystemUiOverlay fromValue(@NonNull String encodedName) throws NoSuchFieldException {
      for (SystemUiOverlay overlay : SystemUiOverlay.values()) {
        if (overlay.encodedName.equals(encodedName)) {
          return overlay;
        }
      }
      throw new NoSuchFieldException("No such SystemUiOverlay: " + encodedName);
    }
 
    @NonNull private String encodedName;
 
    SystemUiOverlay(@NonNull String encodedName) {
      this.encodedName = encodedName;
    }
  }
 
  /** The set of Android system fullscreen modes as perceived by the Flutter application. */
  public enum SystemUiMode {
    LEAN_BACK("SystemUiMode.leanBack"),
    IMMERSIVE("SystemUiMode.immersive"),
    IMMERSIVE_STICKY("SystemUiMode.immersiveSticky"),
    EDGE_TO_EDGE("SystemUiMode.edgeToEdge");
 
    /**
     * Returns the SystemUiMode for the provied encoded value. @throws NoSuchFieldException if any
     * of the given encoded overlay names are invalid.
     */
    @NonNull
    static SystemUiMode fromValue(@NonNull String encodedName) throws NoSuchFieldException {
      for (SystemUiMode mode : SystemUiMode.values()) {
        if (mode.encodedName.equals(encodedName)) {
          return mode;
        }
      }
      throw new NoSuchFieldException("No such SystemUiMode: " + encodedName);
    }
 
    @NonNull private String encodedName;
 
    /** Returens the encoded {@link SystemUiMode} */
    SystemUiMode(@NonNull String encodedName) {
      this.encodedName = encodedName;
    }
  }
 
  /**
   * The color and label of an application that appears in Android's app switcher, AKA recents
   * screen.
   */
  public static class AppSwitcherDescription {
    // TODO(mattcarroll): add color annotation
    public final int color;
    @NonNull public final String label;
 
    public AppSwitcherDescription(int color, @NonNull String label) {
      this.color = color;
      this.label = label;
    }
  }
 
  /** The color and brightness of system chrome, e.g., status bar and system navigation bar. */
  public static class SystemChromeStyle {
    // TODO(mattcarroll): add color annotation
    @Nullable public final Integer statusBarColor;
    @Nullable public final Brightness statusBarIconBrightness;
    @Nullable public final Boolean systemStatusBarContrastEnforced;
    // TODO(mattcarroll): add color annotation
    @Nullable public final Integer systemNavigationBarColor;
    @Nullable public final Brightness systemNavigationBarIconBrightness;
    // TODO(mattcarroll): add color annotation
    @Nullable public final Integer systemNavigationBarDividerColor;
    @Nullable public final Boolean systemNavigationBarContrastEnforced;
 
    public SystemChromeStyle(
        @Nullable Integer statusBarColor,
        @Nullable Brightness statusBarIconBrightness,
        @Nullable Boolean systemStatusBarContrastEnforced,
        @Nullable Integer systemNavigationBarColor,
        @Nullable Brightness systemNavigationBarIconBrightness,
        @Nullable Integer systemNavigationBarDividerColor,
        @Nullable Boolean systemNavigationBarContrastEnforced) {
      this.statusBarColor = statusBarColor;
      this.statusBarIconBrightness = statusBarIconBrightness;
      this.systemStatusBarContrastEnforced = systemStatusBarContrastEnforced;
      this.systemNavigationBarColor = systemNavigationBarColor;
      this.systemNavigationBarIconBrightness = systemNavigationBarIconBrightness;
      this.systemNavigationBarDividerColor = systemNavigationBarDividerColor;
      this.systemNavigationBarContrastEnforced = systemNavigationBarContrastEnforced;
    }
  }
 
  public enum Brightness {
    LIGHT("Brightness.light"),
    DARK("Brightness.dark");
 
    @NonNull
    static Brightness fromValue(@NonNull String encodedName) throws NoSuchFieldException {
      for (Brightness brightness : Brightness.values()) {
        if (brightness.encodedName.equals(encodedName)) {
          return brightness;
        }
      }
      throw new NoSuchFieldException("No such Brightness: " + encodedName);
    }
 
    @NonNull private String encodedName;
 
    Brightness(@NonNull String encodedName) {
      this.encodedName = encodedName;
    }
  }
 
  /** Data formats of clipboard content. */
  public enum ClipboardContentFormat {
    PLAIN_TEXT("text/plain");
 
    @NonNull
    static ClipboardContentFormat fromValue(@NonNull String encodedName)
        throws NoSuchFieldException {
      for (ClipboardContentFormat format : ClipboardContentFormat.values()) {
        if (format.encodedName.equals(encodedName)) {
          return format;
        }
      }
      throw new NoSuchFieldException("No such ClipboardContentFormat: " + encodedName);
    }
 
    @NonNull private String encodedName;
 
    ClipboardContentFormat(@NonNull String encodedName) {
      this.encodedName = encodedName;
    }
  }
}