构建自动填充服务

override fun onFillRequest(
    request: FillRequest,
    cancellationSignal: CancellationSignal,
    callback: FillCallback
) {
    // Get the structure from the request
    val context: List<FillContext> = request.fillContexts
    val structure: AssistStructure = context[context.size - 1].structure

    // Traverse the structure looking for nodes to fill out
    val parsedStructure: ParsedStructure = parseStructure(structure)

    // Fetch user data that matches the fields
    val (username: String, password: String) = fetchUserData(parsedStructure)

    // Build the presentation of the datasets
    val usernamePresentation = RemoteViews(packageName, android.R.layout.simple_list_item_1)
    usernamePresentation.setTextViewText(android.R.id.text1, "my_username")
    val passwordPresentation = RemoteViews(packageName, android.R.layout.simple_list_item_1)
    passwordPresentation.setTextViewText(android.R.id.text1, "Password for my_username")

    // Add a dataset to the response
    val fillResponse: FillResponse = FillResponse.Builder()
            .addDataset(Dataset.Builder()
                    .setValue(
                            parsedStructure.usernameId,
                            AutofillValue.forText(username),
                            usernamePresentation
                    )
                    .setValue(
                            parsedStructure.passwordId,
                            AutofillValue.forText(password),
                            passwordPresentation
                    )
                    .build())
            .build()

    // If there are no errors, call onSuccess() and pass the response
    callback.onSuccess(fillResponse)
}

data class ParsedStructure(var usernameId: AutofillId, var passwordId: AutofillId)

data class UserData(var username: String, var password: String)

@Override
public void onFillRequest(FillRequest request, CancellationSignal cancellationSignal, FillCallback callback) {
    // Get the structure from the request
    List<FillContext> context = request.getFillContexts();
    AssistStructure structure = context.get(context.size() - 1).getStructure();

    // Traverse the structure looking for nodes to fill out
    ParsedStructure parsedStructure = parseStructure(structure);

    // Fetch user data that matches the fields
    UserData userData = fetchUserData(parsedStructure);

    // Build the presentation of the datasets
    RemoteViews usernamePresentation = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);
    usernamePresentation.setTextViewText(android.R.id.text1, "my_username");
    RemoteViews passwordPresentation = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);
    passwordPresentation.setTextViewText(android.R.id.text1, "Password for my_username");

    // Add a dataset to the response
    FillResponse fillResponse = new FillResponse.Builder()
            .addDataset(new Dataset.Builder()
                    .setValue(parsedStructure.usernameId,
                            AutofillValue.forText(userData.username), usernamePresentation)
                    .setValue(parsedStructure.passwordId,
                            AutofillValue.forText(userData.password), passwordPresentation)
                    .build())
            .build();

    // If there are no errors, call onSuccess() and pass the response
    callback.onSuccess(fillResponse);
}

class ParsedStructure {
    AutofillId usernameId;
    AutofillId passwordId;
}

class UserData {
    String username;
    String password;
}

// Add multiple datasets to the response
val fillResponse: FillResponse = FillResponse.Builder()
        .addDataset(Dataset.Builder()
                .setValue(parsedStructure.usernameId,
                        AutofillValue.forText(user1Data.username), username1Presentation)
                .setValue(parsedStructure.passwordId,
                        AutofillValue.forText(user1Data.password), password1Presentation)
                .build())
        .addDataset(Dataset.Builder()
                .setValue(parsedStructure.usernameId,
                        AutofillValue.forText(user2Data.username), username2Presentation)
                .setValue(parsedStructure.passwordId,
                        AutofillValue.forText(user2Data.password), password2Presentation)
                .build())
        .build()

// Add multiple datasets to the response
FillResponse fillResponse = new FillResponse.Builder()
        .addDataset(new Dataset.Builder()
                .setValue(parsedStructure.usernameId,
                        AutofillValue.forText(user1Data.username), username1Presentation)
                .setValue(parsedStructure.passwordId,
                        AutofillValue.forText(user1Data.password), password1Presentation)
                .build())
        .addDataset(new Dataset.Builder()
                .setValue(parsedStructure.usernameId,
                        AutofillValue.forText(user2Data.username), username2Presentation)
                .setValue(parsedStructure.passwordId,
                        AutofillValue.forText(user2Data.password), password2Presentation)
                .build())
        .build();

fun traverseStructure(structure: AssistStructure) {
    val windowNodes: List<AssistStructure.WindowNode> =
            structure.run {
                (0 until windowNodeCount).map { getWindowNodeAt(it) }
            }

    windowNodes.forEach { windowNode: AssistStructure.WindowNode ->
        val viewNode: ViewNode? = windowNode.rootViewNode
        traverseNode(viewNode)
    }
}

fun traverseNode(viewNode: ViewNode?) {
    if (viewNode?.autofillHints?.isNotEmpty() == true) {
        // If the client app provides autofill hints, you can obtain them using
        // viewNode.getAutofillHints();
    } else {
        // Or use your own heuristics to describe the contents of a view
        // using methods such as getText() or getHint()
    }

    val children: List<ViewNode>? =
            viewNode?.run {
                (0 until childCount).map { getChildAt(it) }
            }

    children?.forEach { childNode: ViewNode ->
        traverseNode(childNode)
    }
}

public void traverseStructure(AssistStructure structure) {
    int nodes = structure.getWindowNodeCount();

    for (int i = 0; i < nodes; i++) {
        WindowNode windowNode = structure.getWindowNodeAt(i);
        ViewNode viewNode = windowNode.getRootViewNode();
        traverseNode(viewNode);
    }
}

public void traverseNode(ViewNode viewNode) {
    if(viewNode.getAutofillHints() != null && viewNode.getAutofillHints().length > 0) {
        // If the client app provides autofill hints, you can obtain them using
        // viewNode.getAutofillHints();
    } else {
        // Or use your own heuristics to describe the contents of a view
        // using methods such as getText() or getHint()
    }

    for(int i = 0; i < viewNode.getChildCount(); i++) {
        ViewNode childNode = viewNode.getChildAt(i);
        traverseNode(childNode);
    }
}

override fun onFillRequest(
    request: FillRequest,
    cancellationSignal: CancellationSignal,
    callback: FillCallback
) {
    ...
    // Builder object requires a non-null presentation
    val notUsed = RemoteViews(packageName, android.R.layout.simple_list_item_1)

    val fillResponse: FillResponse = FillResponse.Builder()
            .addDataset(
                    Dataset.Builder()
                            .setValue(parsedStructure.usernameId, null, notUsed)
                            .setValue(parsedStructure.passwordId, null, notUsed)
                            .build()
            )
            .setSaveInfo(
                    SaveInfo.Builder(
                            SaveInfo.SAVE_DATA_TYPE_USERNAME or SaveInfo.SAVE_DATA_TYPE_PASSWORD,
                            arrayOf(parsedStructure.usernameId, parsedStructure.passwordId)
                    ).build()
            )
            .build()
    ...
}

@Override
public void onFillRequest(FillRequest request, CancellationSignal cancellationSignal, FillCallback callback) {
    ...
    // Builder object requires a non-null presentation
    RemoteViews notUsed = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);

    FillResponse fillResponse = new FillResponse.Builder()
            .addDataset(new Dataset.Builder()
                    .setValue(parsedStructure.usernameId, null, notUsed)
                    .setValue(parsedStructure.passwordId, null, notUsed)
                    .build())
            .setSaveInfo(new SaveInfo.Builder(
                    SaveInfo.SAVE_DATA_TYPE_USERNAME | SaveInfo.SAVE_DATA_TYPE_PASSWORD,
                    new AutofillId[] {parsedStructure.usernameId, parsedStructure.passwordId})
                    .build())
            .build();
    ...
}

override fun onSaveRequest(request: SaveRequest, callback: SaveCallback) {
    // Get the structure from the request
    val context: List<FillContext> = request.fillContexts
    val structure: AssistStructure = context[context.size - 1].structure

    // Traverse the structure looking for data to save
    traverseStructure(structure)

    // Persist the data - if there are no errors, call onSuccess()
    callback.onSuccess()
}

@Override
public void onSaveRequest(SaveRequest request, SaveCallback callback) {
    // Get the structure from the request
    List<FillContext> context = request.getFillContexts();
    AssistStructure structure = context.get(context.size() - 1).getStructure();

    // Traverse the structure looking for data to save
    traverseStructure(structure);

    // Persist the data - if there are no errors, call onSuccess()
    callback.onSuccess();
}

val authPresentation = RemoteViews(packageName, android.R.layout.simple_list_item_1).apply {
    setTextViewText(android.R.id.text1, "requires authentication")
}
val authIntent = Intent(this, AuthActivity::class.java).apply {
    // Send any additional data required to complete the request
    putExtra(MY_EXTRA_DATASET_NAME, "my_dataset")
}

val intentSender: IntentSender = PendingIntent.getActivity(
        this,
        1001,
        authIntent,
        PendingIntent.FLAG_CANCEL_CURRENT
).intentSender

// Build a FillResponse object that requires authentication
val fillResponse: FillResponse = FillResponse.Builder()
        .setAuthentication(autofillIds, intentSender, authPresentation)
        .build()

RemoteViews authPresentation = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);
authPresentation.setTextViewText(android.R.id.text1, "requires authentication");
Intent authIntent = new Intent(this, AuthActivity.class);

// Send any additional data required to complete the request
authIntent.putExtra(MY_EXTRA_DATASET_NAME, "my_dataset");
IntentSender intentSender = PendingIntent.getActivity(
                this,
                1001,
                authIntent,
                PendingIntent.FLAG_CANCEL_CURRENT
        ).getIntentSender();

// Build a FillResponse object that requires authentication
FillResponse fillResponse = new FillResponse.Builder()
        .setAuthentication(autofillIds, intentSender, authPresentation)
        .build();

// The data sent by the service and the structure are included in the intent
val datasetName: String? = intent.getStringExtra(MY_EXTRA_DATASET_NAME)
val structure: AssistStructure = intent.getParcelableExtra(EXTRA_ASSIST_STRUCTURE)
val parsedStructure: ParsedStructure = parseStructure(structure)
val (username, password) = fetchUserData(parsedStructure)

// Build the presentation of the datasets
val usernamePresentation =
        RemoteViews(packageName, android.R.layout.simple_list_item_1).apply {
            setTextViewText(android.R.id.text1, "my_username")
        }
val passwordPresentation =
        RemoteViews(packageName, android.R.layout.simple_list_item_1).apply {
            setTextViewText(android.R.id.text1, "Password for my_username")
        }

// Add the dataset to the response
val fillResponse: FillResponse = FillResponse.Builder()
        .addDataset(Dataset.Builder()
                .setValue(
                        parsedStructure.usernameId,
                        AutofillValue.forText(username),
                        usernamePresentation
                )
                .setValue(
                        parsedStructure.passwordId,
                        AutofillValue.forText(password),
                        passwordPresentation
                )
                .build()
        ).build()

val replyIntent = Intent().apply {
    // Send the data back to the service
    putExtra(MY_EXTRA_DATASET_NAME, datasetName)
    putExtra(EXTRA_AUTHENTICATION_RESULT, fillResponse)
}

setResult(Activity.RESULT_OK, replyIntent)

Intent intent = getIntent();

// The data sent by the service and the structure are included in the intent
String datasetName = intent.getStringExtra(MY_EXTRA_DATASET_NAME);
AssistStructure structure = intent.getParcelableExtra(EXTRA_ASSIST_STRUCTURE);
ParsedStructure parsedStructure = parseStructure(structure);
UserData userData = fetchUserData(parsedStructure);

// Build the presentation of the datasets
RemoteViews usernamePresentation = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);
usernamePresentation.setTextViewText(android.R.id.text1, "my_username");
RemoteViews passwordPresentation = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);
passwordPresentation.setTextViewText(android.R.id.text1, "Password for my_username");

// Add the dataset to the response
FillResponse fillResponse = new FillResponse.Builder()
        .addDataset(new Dataset.Builder()
                .setValue(parsedStructure.usernameId,
                        AutofillValue.forText(userData.username), usernamePresentation)
                .setValue(parsedStructure.passwordId,
                        AutofillValue.forText(userData.password), passwordPresentation)
                .build())
        .build();

Intent replyIntent = new Intent();

// Send the data back to the service
replyIntent.putExtra(MY_EXTRA_DATASET_NAME, datasetName);
replyIntent.putExtra(EXTRA_AUTHENTICATION_RESULT, fillResponse);

setResult(RESULT_OK, replyIntent);

// Parse the structure and fetch payment data
val parsedStructure: ParsedStructure = parseStructure(structure)
val paymentData: Payment = fetchPaymentData(parsedStructure)

// Build the presentation that shows the bank and the last four digits of the
// credit card number, such as 'Bank-1234'
val maskedPresentation: String = "${paymentData.bank}-" +
        paymentData.creditCardNumber.substring(paymentData.creditCardNumber.length - 4)
val authPresentation = RemoteViews(packageName, android.R.layout.simple_list_item_1).apply {
    setTextViewText(android.R.id.text1, maskedPresentation)
}

// Prepare an intent that displays the UI that asks for the CVC
val cvcIntent = Intent(this, CvcActivity::class.java)
val cvcIntentSender: IntentSender = PendingIntent.getActivity(
        this,
        1001,
        cvcIntent,
        PendingIntent.FLAG_CANCEL_CURRENT
).intentSender

// Build a FillResponse object that includes a Dataset that requires authentication
val fillResponse: FillResponse = FillResponse.Builder()
        .addDataset(
                Dataset.Builder()
                        // The values in the dataset are replaced by the actual
                        // data once the user provides the CVC
                        .setValue(parsedStructure.creditCardId, null, authPresentation)
                        .setValue(parsedStructure.expDateId, null, authPresentation)
                        .setAuthentication(cvcIntentSender)
                        .build()
        ).build()

// Parse the structure and fetch payment data
ParsedStructure parsedStructure = parseStructure(structure);
Payment paymentData = fetchPaymentData(parsedStructure);

// Build the presentation that shows the bank and the last four digits of the
// credit card number, such as 'Bank-1234'
String maskedPresentation = paymentData.bank + "-" +
    paymentData.creditCardNumber.subString(paymentData.creditCardNumber.length - 4);
RemoteViews authPresentation = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);
authPresentation.setTextViewText(android.R.id.text1, maskedPresentation);

// Prepare an intent that displays the UI that asks for the CVC
Intent cvcIntent = new Intent(this, CvcActivity.class);
IntentSender cvcIntentSender = PendingIntent.getActivity(
        this,
        1001,
        cvcIntent,
        PendingIntent.FLAG_CANCEL_CURRENT
).getIntentSender();

// Build a FillResponse object that includes a Dataset that requires authentication
FillResponse fillResponse = new FillResponse.Builder()
        .addDataset(new Dataset.Builder()
                // The values in the dataset are replaced by the actual
                // data once the user provides the CVC
                .setValue(parsedStructure.creditCardId, null, authPresentation)
                .setValue(parsedStructure.expDateId, null, authPresentation)
                .setAuthentication(cvcIntentSender)
                .build())
        .build();

// Parse the structure and fetch payment data.
val parsedStructure: ParsedStructure = parseStructure(structure)
val paymentData: Payment = fetchPaymentData(parsedStructure)

// Build a non-null RemoteViews object to use as the presentation when
// creating the Dataset object. This presentation isn't actually used, but the
// Builder object requires a non-null presentation.
val notUsed = RemoteViews(packageName, android.R.layout.simple_list_item_1)

// Create a dataset with the credit card number and expiration date.
val responseDataset: Dataset = Dataset.Builder()
        .setValue(
                parsedStructure.creditCardId,
                AutofillValue.forText(paymentData.creditCardNumber),
                notUsed
        )
        .setValue(
                parsedStructure.expDateId,
                AutofillValue.forText(paymentData.expirationDate),
                notUsed
        )
        .build()

val replyIntent = Intent().apply {
    putExtra(EXTRA_AUTHENTICATION_RESULT, responseDataset)
}

// Parse the structure and fetch payment data.
ParsedStructure parsedStructure = parseStructure(structure);
Payment paymentData = fetchPaymentData(parsedStructure);

// Build a non-null RemoteViews object to use as the presentation when
// creating the Dataset object. This presentation isn't actually used, but the
// Builder object requires a non-null presentation.
RemoteViews notUsed = new RemoteViews(getPackageName(), android.R.layout.simple_list_item_1);

// Create a dataset with the credit card number and expiration date.
Dataset responseDataset = new Dataset.Builder()
        .setValue(parsedStructure.creditCardId,
                AutofillValue.forText(paymentData.creditCardNumber), notUsed)
        .setValue(parsedStructure.expDateId,
                AutofillValue.forText(paymentData.expirationDate), notUsed)
        .build();

Intent replyIntent = new Intent();
replyIntent.putExtra(EXTRA_AUTHENTICATION_RESULT, responseDataset);

val CHROME_CHANNEL_PACKAGE = "com.android.chrome" // Chrome Stable.
val CONTENT_PROVIDER_NAME = ".AutofillThirdPartyModeContentProvider"
val THIRD_PARTY_MODE_COLUMN = "autofill_third_party_state"
val THIRD_PARTY_MODE_ACTIONS_URI_PATH = "autofill_third_party_mode"

val uri = Uri.Builder()
    .scheme(ContentResolver.SCHEME_CONTENT)
    .authority(CHROME_CHANNEL_PACKAGE + CONTENT_PROVIDER_NAME)
    .path(THIRD_PARTY_MODE_ACTIONS_URI_PATH)
    .build()

val cursor = contentResolver.query(
    uri,
    arrayOf(THIRD_PARTY_MODE_COLUMN), // projection
    null, // selection
    null, // selectionArgs
    null  // sortOrder
)

if (cursor == null) {
  // Terminate now! Older versions of Chromium don't provide this information.
}

cursor?.use { // Use the safe call operator and the use function for auto-closing
    if (it.moveToFirst()) { // Check if the cursor has any rows
        val index = it.getColumnIndex(THIRD_PARTY_MODE_COLUMN)
        if (index != -1) { // Check if the column exists
          val value = it.getInt(index)
          if (0 == value) {
              // 0 means that the third party mode is turned off. Chrome uses its built-in
              // password manager. This is the default for new users.
          } else {
              // 1 means that the third party mode is turned on. Chrome uses forwards all
              // autofill requests to Android Autofill. Users have to opt-in for this.
          }
        } else {
          // Handle the case where the column doesn't exist.  Log a warning, perhaps.
          Log.w("Autofill", "Column $THIRD_PARTY_MODE_COLUMN not found in cursor")
        }
    }
} // The cursor is automatically closed here

final String CHROME_CHANNEL_PACKAGE = "com.android.chrome";  // Chrome Stable.
final String CONTENT_PROVIDER_NAME = ".AutofillThirdPartyModeContentProvider";
final String THIRD_PARTY_MODE_COLUMN = "autofill_third_party_state";
final String THIRD_PARTY_MODE_ACTIONS_URI_PATH = "autofill_third_party_mode";

final Uri uri = new Uri.Builder()
                  .scheme(ContentResolver.SCHEME_CONTENT)
                  .authority(CHROME_CHANNEL_PACKAGE + CONTENT_PROVIDER_NAME)
                  .path(THIRD_PARTY_MODE_ACTIONS_URI_PATH)
                  .build();

final Cursor cursor = getContentResolver().query(
                  uri,
                  /*projection=*/new String[] {THIRD_PARTY_MODE_COLUMN},
                  /*selection=*/ null,
                  /*selectionArgs=*/ null,
                  /*sortOrder=*/ null);

if (cursor == null) {
  // Terminate now! Older versions of Chromium don't provide this information.
}

cursor.moveToFirst(); // Retrieve the result;

int index = cursor.getColumnIndex(THIRD_PARTY_MODE_COLUMN);

if (0 == cursor.getInt(index)) {
  // 0 means that the third party mode is turned off. Chrome uses its built-in
  // password manager. This is the default for new users.
} else {
  // 1 means that the third party mode is turned on. Chrome uses forwards all
  // autofill requests to Android Autofill. Users have to opt-in for this.
}

val autofillSettingsIntent = Intent(Intent.ACTION_APPLICATION_PREFERENCES)
autofillSettingsIntent.addCategory(Intent.CATEGORY_DEFAULT)
autofillSettingsIntent.addCategory(Intent.CATEGORY_APP_BROWSER)
autofillSettingsIntent.addCategory(Intent.CATEGORY_PREFERENCE)

// Invoking the intent with a chooser allows users to select the channel they
// want to configure. If only one browser reacts to the intent, the chooser is
// skipped.
val chooser = Intent.createChooser(autofillSettingsIntent, "Pick Chrome Channel")
startActivity(chooser)

// If the caller knows which Chrome channel they want to configure,
// they can instead add a package hint to the intent, e.g.
val specificChromeIntent = Intent(Intent.ACTION_APPLICATION_PREFERENCES) // Create a *new* intent
specificChromeIntent.addCategory(Intent.CATEGORY_DEFAULT)
specificChromeIntent.addCategory(Intent.CATEGORY_APP_BROWSER)
specificChromeIntent.addCategory(Intent.CATEGORY_PREFERENCE)
specificChromeIntent.setPackage("com.android.chrome") // Set the package on the *new* intent
startActivity(specificChromeIntent) // Start the *new* intent

Intent autofillSettingsIntent = new Intent(Intent.ACTION_APPLICATION_PREFERENCES);
autofillSettingsIntent.addCategory(Intent.CATEGORY_DEFAULT);
autofillSettingsIntent.addCategory(Intent.CATEGORY_APP_BROWSER);
autofillSettingsIntent.addCategory(Intent.CATEGORY_PREFERENCE);

// Invoking the intent with a chooser allows users to select the channel they
// want to configure. If only one browser reacts to the intent, the chooser is
// skipped.
Intent chooser = Intent.createChooser(autofillSettingsIntent, "Pick Chrome Channel");
startActivity(chooser);

// If the caller knows which Chrome channel they want to configure,
// they can instead add a package hint to the intent, e.g.
autofillSettingsIntent.setPackage("com.android.chrome");
startActivity(autofillSettingsInstent);