@ohos.data.unifiedDataChannel (Unified Data Channel)

As a part of the Unified Data Management Framework (UDMF), the unifiedDataChannel module provides unified data channels and standard data access interfaces for many-to-many data sharing across applications. It also provides standard definitions for data types, such as text and image, to streamline data interaction between different applications and minimize the workload of data type adaptation.

NOTE

The initial APIs of this module are supported since API version 10. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';

UnifiedData

Provides APIs for encapsulating a set of data records.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

constructor

constructor(record: UnifiedRecord)

A constructor used to create a UnifiedData object with a data record.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
record	UnifiedRecord	Yes	Data record in the UnifiedData object. It is a UnifiedRecord child class object.

Example

let text = new unifiedDataChannel.PlainText();
text.textContent = 'this is textContent of text';
let unifiedData = new unifiedDataChannel.UnifiedData(text);

addRecord

addRecord(record: UnifiedRecord): void

Adds a data record to this UnifiedRecord object.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
record	UnifiedRecord	Yes	Data record to add. It is a UnifiedRecord child class object.

Example

let text1 = new unifiedDataChannel.PlainText();
text1.textContent = 'this is textContent of text1';
let unifiedData = new unifiedDataChannel.UnifiedData(text1);

let text2 = new unifiedDataChannel.PlainText();
text2.textContent = 'this is textContent of text2';
unifiedData.addRecord(text2);

getRecords

getRecords(): Array<UnifiedRecord>

Obtains all data records from this UnifiedData object. The data obtained is of the UnifiedRecord type. Before using the data, you need to use getType to obtain the data type and convert the data type to a child class.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Return value

Type	Description
Array<UnifiedRecord>	Records in the UnifiedData object obtained.

Example

import uniformTypeDescriptor from '@ohos.data.uniformTypeDescriptor';

let text = new unifiedDataChannel.PlainText();
text.textContent = 'this is textContent of text';
let unifiedData = new unifiedDataChannel.UnifiedData(text);

let link = new unifiedDataChannel.Hyperlink();
link.url = 'www.XXX.com';
unifiedData.addRecord(link);

let records = unifiedData.getRecords();
for (let i = 0; i < records.length; i++) {
  let record = records[i];
  if (record.getType() == uniformTypeDescriptor.UniformDataType.PLAIN_TEXT) {
    let plainText = record as unifiedDataChannel.PlainText;
    console.info(`textContent: ${plainText.textContent}`);
  } else if (record.getType() == uniformTypeDescriptor.UniformDataType.HYPERLINK) {
    let hyperlink = record as unifiedDataChannel.Hyperlink;
    console.info(`linkUrl: ${hyperlink.url}`);
  }
}

Summary

Defines the summary of a UnifiedData object, including the data types and sizes. Currently, it is not supported.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
summary	{ [key: string]: number }	Yes	No	Dictionary type object, where the key indicates the data type (see UniformDataType), and the value indicates the total size (in bytes) of this type of records in the UnifiedData object.
totalSize	number	Yes	No	Total size of all the records in the UnifiedData object, in bytes.

UnifiedRecord

An abstract definition of the data content supported by the UDMF. A UnifiedRecord object contains one or more data records, for example, a text record, an image record, or an HTML record.

UnifiedRecord is an abstract parent class that does not hold specific data content. It cannot be added to a UnifiedData object directly. Instead, a child class with specific content, such as text and image, must be created.

getType

getType(): string

Obtains the type of this UnfiedRecord. The data obtained by getRecords from the UnifiedData object is a UnifiedRecord object. You need to use this API to obtain the specific type of the record, convert the UnifiedRecord object to its child class, and call the child class interfaces.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Return value

Type	Description
string	Data type obtained. For details, see UniformDataType.

Example

import uniformTypeDescriptor from '@ohos.data.uniformTypeDescriptor';

let text = new unifiedDataChannel.PlainText();
text.textContent = 'this is textContent of text';
let unifiedData = new unifiedDataChannel.UnifiedData(text);

let records = unifiedData.getRecords();
if (records[0].getType() == uniformTypeDescriptor.UniformDataType.PLAIN_TEXT) {
  let plainText = records[0] as unifiedDataChannel.PlainText;
  console.info(`textContent: ${plainText.textContent}`);
}

Text

Represents the text data. It is a child class of UnifiedRecord and a base class of text data. You are advised to use the child class of Text, for example, PlainText, Hyperlink, and HTML, to describe data.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
details	{ [key: string]: string }	Yes	Yes	A dictionary type object, where both the key and value are of the string type and are used to describe the text content. For example, a data object with the following content can be created to describe a text file: { "title":"Title", "content":"Content" } This parameter is optional. The default value is an empty dictionary object.

Example

let text = new unifiedDataChannel.Text();
text.details = {
  title: 'MyTitle',
  content: 'this is content',
};
let unifiedData = new unifiedDataChannel.UnifiedData(text);

PlainText

Represents the plaintext data. It is a child class of Text and is used to describe plaintext data.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
textContent	string	Yes	Yes	Plaintext content.
abstract	string	Yes	Yes	Text abstract. This parameter is optional. The default value is an empty string.

Example

let text = new unifiedDataChannel.PlainText();
text.textContent = 'this is textContent';
text.abstract = 'this is abstract';

Hyperlink

Represents hyperlink data. It is a child class of Text and is used to describe data of the hyperlink type.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
url	string	Yes	Yes	URL.
description	string	Yes	Yes	Description of the linked content. This parameter is optional. The default value is an empty string.

Example

let link = new unifiedDataChannel.Hyperlink();
link.url = 'www.XXX.com';
link.description = 'this is description';

HTML

Represents the HTML data. It is a child class of Text and is used to describe HTML data.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
htmlContent	string	Yes	Yes	Content in HTML format.
plainContent	string	Yes	Yes	Plaintext without HTML tags. This parameter is optional. The default value is an empty string.

Example

let html = new unifiedDataChannel.HTML();
html.htmlContent = '<div><p>Title</p></div>';
html.plainContent = 'this is plainContent';

File

Represents the file data. It is a child class of UnifiedRecord and a base class of the data of the file type. You are advised to use the child class of File, for example, Image, Video, and Folder, to describe data.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
details	{ [key: string]: string }	Yes	Yes	A dictionary type object, where both the key and value are of the string type and are used to describe file information. For example, a data object with the following content can be created to describe a file: { "name":"File name", "type":"File type" } This parameter is optional. The default value is an empty dictionary object.
uri	string	Yes	Yes	URI of the file data.

Example

let file = new unifiedDataChannel.File();
file.details = {
    name: 'test',
    type: 'txt',
};
file.uri = 'schema://com.samples.test/files/test.txt';

Image

Represents the image data. It is a child class of File and is used to describe images.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
imageUri	string	Yes	Yes	URI of the image.

Example

let image = new unifiedDataChannel.Image();
image.imageUri = 'schema://com.samples.test/files/test.jpg';

Video

Represents video data. It is a child class of File and is used to describe a video file.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
videoUri	string	Yes	Yes	URI of the video file.

Example

let video = new unifiedDataChannel.Video();
video.videoUri = 'schema://com.samples.test/files/test.mp4';

Audio

Represents video data. It is a child class of File and is used to describe a video file.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
audioUri	string	Yes	Yes	Audio data URI.

Example

let audio = new unifiedDataChannel.Audio();
audio.audioUri = 'schema://com.samples.test/files/test.mp3';

Folder

Represents the folder data. It is a child class of File and is used to describe a folder.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
folderUri	string	Yes	Yes	URI of the folder.

Example

let folder = new unifiedDataChannel.Folder();
folder.folderUri = 'schema://com.samples.test/files/folder/';

SystemDefinedRecord

Represents specific data types defined by OpenHarmony. It is a child class of UnifiedRecord and a base class of OpenHarmony-specific data types. You are advised to use the child class of SystemDefinedRecord, for example, SystemDefinedForm, SystemDefinedAppItem, and SystemDefinedPixelMap, to describe OpenHarmony-specific data.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
details	{ [key: string]: number \|string \|Uint8Array }	Yes	Yes	A dictionary type object, where the key is of the string type, and the value can be a number, a string, or a Uint8Array. This parameter is optional. The default value is an empty dictionary object.

Example

let sdr = new unifiedDataChannel.SystemDefinedRecord();
let u8Array = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
sdr.details = {
    title: 'recordTitle',
    version: 1,
    content: u8Array,
};
let unifiedData = new unifiedDataChannel.UnifiedData(sdr);

SystemDefinedForm

Represents the widget data. It is a child class of SystemDefinedRecord.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
formId	number	Yes	Yes	Service widget ID.
formName	string	Yes	Yes	Widget name.
bundleName	string	Yes	Yes	Name of the bundle to which a widget belongs.
abilityName	string	Yes	Yes	Ability name corresponding to the widget.
module	string	Yes	Yes	Name of the module to which the widget belongs.

Example

let form = new unifiedDataChannel.SystemDefinedForm();
form.formId = 123456;
form.formName = 'MyFormName';
form.bundleName = 'MyBundleName';
form.abilityName = 'MyAbilityName';
form.module = 'MyModule';
let u8Array = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
form.details = {
  formKey1: 123,
  formKey2: 'formValue',
  formKey3: u8Array,
};
let unifiedData = new unifiedDataChannel.UnifiedData(form);

SystemDefinedAppItem

Represents the icon data. It is a child class of SystemDefinedRecord.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
appId	string	Yes	Yes	ID of the application, for which the icon is used.
appName	string	Yes	Yes	Name of the application, for which the icon is used.
appIconId	string	Yes	Yes	Image ID of the icon.
appLabelId	string	Yes	Yes	Label ID corresponding to the icon name.
bundleName	string	Yes	Yes	Bundle name corresponding to the icon.
abilityName	string	Yes	Yes	Application ability name corresponding to the icon.

Example

let appItem = new unifiedDataChannel.SystemDefinedAppItem();
appItem.appId = 'MyAppId';
appItem.appName = 'MyAppName';
appItem.appIconId = 'MyAppIconId';
appItem.appLabelId = 'MyAppLabelId';
appItem.bundleName = 'MyBundleName';
appItem.abilityName = 'MyAbilityName';
let u8Array = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
appItem.details = {
    appItemKey1: 123,
    appItemKey2: 'appItemValue',
    appItemKey3: u8Array,
};
let unifiedData = new unifiedDataChannel.UnifiedData(appItem);

SystemDefinedPixelMap

Represents the image data corresponding to the PixelMap defined by OpenHarmony. It is a child class of SystemDefinedRecord and used to store only the binary data of PixelMap.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
rawData	Uint8Array	Yes	Yes	Binary data of the PixelMap object.

Example

import image from '@ohos.multimedia.image'; // Module where the PixelMap class is defined.

const color = new ArrayBuffer(96); // Create a PixelMap object.
let opts: image.InitializationOptions = {
  editable: true, pixelFormat: 3, size: {
    height: 4, width: 6
  }
}
image.createPixelMap(color, opts, (error, pixelmap) => {
  if (error) {
    console.error('Failed to create pixelmap.');
  } else {
    console.info('Succeeded in creating pixelmap.');
    let arrayBuf = new ArrayBuffer(pixelmap.getPixelBytesNumber());
    pixelmap.readPixelsToBuffer(arrayBuf);
    let u8Array = new Uint8Array(arrayBuf);
    let sdpixel = new unifiedDataChannel.SystemDefinedPixelMap();
    sdpixel.rawData = u8Array;
    let unifiedData = new unifiedDataChannel.UnifiedData(sdpixel);
  }
})

ApplicationDefinedRecord

Represents the custom data type for applications only. It is a child class of UnifiedRecord and a base class of custom data types of applications. Applications can extend custom data types based on this class.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Description
applicationDefinedType	string	Yes	Yes	Application's custom data type identifier, which must start with ApplicationDefined.
rawData	Uint8Array	Yes	Yes	Binary data of the custom data type.

Example

let record = new unifiedDataChannel.ApplicationDefinedRecord();
let u8Array = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
record.applicationDefinedType = 'ApplicationDefinedType';
record.rawData = u8Array;
let unifiedData = new unifiedDataChannel.UnifiedData(record);

Intention

Enumerates the data channel types supported by the UDMF. It is used to identify different service scenarios, to which the UDMF data channels apply.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Value	Description
DATA_HUB	'DataHub'	Public data channel.

Options

Defines the data operation performed by the UDMF. It includes two optional parameters: intention and key. The two parameters have no default value, and can be left unspecified. For details, see the parameter description of the specific API.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Name	Type	Readable	Writable	Mandatory	Description
intention	Intention	Yes	Yes	No	Type of the data channel related to the data operation.
key	string	Yes	Yes	No	Unique identifier of the data object in the UDMF, which can be obtained from the value returned by insertData. The key consists of udmf:/, intention, bundleName, and groupId with a (/) in between, for example, udmf://DataHub/com.ohos.test/0123456789. udmf:/ is fixed, DataHub is an enum of intention, com.ohos.test is the bundle name, and 0123456789 is a group ID randomly generated.

unifiedDataChannel.insertData

insertData(options: Options, data: UnifiedData, callback: AsyncCallback<string>): void

Inserts data to the UDMF public data channel. This API uses an asynchronous callback to return the unique identifier of the data inserted.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Only the intention is required.
data	UnifiedData	Yes	Data to insert.
callback	AsyncCallback<string>	Yes	Callback invoked to return the key (unique identifier) of the data inserted.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import { BusinessError } from '@ohos.base';

let plainText = new unifiedDataChannel.PlainText();
plainText.textContent = 'hello world!';
let unifiedData = new unifiedDataChannel.UnifiedData(plainText);

let options: unifiedDataChannel.Options = {
  intention: unifiedDataChannel.Intention.DATA_HUB
}
try {
  unifiedDataChannel.insertData(options, unifiedData, (err, data) => {
    if (err === undefined) {
      console.info(`Succeeded in inserting data. key = ${data}`);
    } else {
      console.error(`Failed to insert data. code is ${err.code},message is ${err.message} `);
    }
  });
  } catch (e) {
    let error: BusinessError = e as BusinessError;
    console.error(`Insert data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.insertData

insertData(options: Options, data: UnifiedData): Promise<string>

Inserts data to the UDMF public data channel. This API uses a promise to return the unique identifier of the data inserted.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Only the intention is required.
data	UnifiedData	Yes	Data to insert.

Return value

Type	Description
Promise<string>	Promise used to return the key of the data inserted.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import { BusinessError } from '@ohos.base';

let plainText = new unifiedDataChannel.PlainText();
plainText.textContent = 'hello world!';
let unifiedData = new unifiedDataChannel.UnifiedData(plainText);

let options: unifiedDataChannel.Options = {
  intention: unifiedDataChannel.Intention.DATA_HUB
}
try {
  unifiedDataChannel.insertData(options, unifiedData).then((data) => {
    console.info(`Succeeded in inserting data. key = ${data}`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to insert data. code is ${err.code},message is ${err.message} `);
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Insert data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.updateData

updateData(options: Options, data: UnifiedData, callback: AsyncCallback<void>): void

Updates the data in the UDMF public data channel. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Only the value of key is required.
data	UnifiedData	Yes	New data.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result. If the data is updated successfully, err is undefined. Otherwise, err is an error object.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import { BusinessError } from '@ohos.base';

let plainText = new unifiedDataChannel.PlainText();
plainText.textContent = 'hello world!';
let unifiedData = new unifiedDataChannel.UnifiedData(plainText);

let options: unifiedDataChannel.Options = {
  key: 'udmf://DataHub/com.ohos.test/0123456789'
};

try {
  unifiedDataChannel.updateData(options, unifiedData, (err) => {
    if (err === undefined) {
      console.info('Succeeded in updating data.');
    } else {
      console.error(`Failed to update data. code is ${err.code},message is ${err.message} `);
    }
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Update data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.updateData

updateData(options: Options, data: UnifiedData): Promise<void>

Updates the data in the UDMF public data channel. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Only the value of key is required.
data	UnifiedData	Yes	New data.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import { BusinessError } from '@ohos.base';

let plainText = new unifiedDataChannel.PlainText();
plainText.textContent = 'hello world!';
let unifiedData = new unifiedDataChannel.UnifiedData(plainText);

let options: unifiedDataChannel.Options = {
  key: 'udmf://DataHub/com.ohos.test/0123456789'
};

try {
  unifiedDataChannel.updateData(options, unifiedData).then(() => {
    console.info('Succeeded in updating data.');
  }).catch((err: BusinessError) => {
    console.error(`Failed to update data. code is ${err.code},message is ${err.message} `);
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Update data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.queryData

queryData(options: Options, callback: AsyncCallback<Array<UnifiedData>>): void

Queries data in the UDMF public data channel. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Both the key and intention are optional, and the return value varies depending on the parameters passed in.
callback	AsyncCallback<Array<UnifiedData>>	Yes	Callback invoked to return the queried data. If only the key is specified in options, the data corresponding to the key is returned. If only the intention is specified in options, all data in the intention is returned. If both intention and key are specified, the intersection of the two is returned, which is the result obtained when only key is specified. If there is no intersection between the specified intention and key, an error object is returned.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import uniformTypeDescriptor from '@ohos.data.uniformTypeDescriptor';
import { BusinessError } from '@ohos.base';

let options: unifiedDataChannel.Options = {
  intention: unifiedDataChannel.Intention.DATA_HUB
};

try {
  unifiedDataChannel.queryData(options, (err, data) => {
    if (err === undefined) {
      console.info(`Succeeded in querying data. size = ${data.length}`);
      for (let i = 0; i < data.length; i++) {
        let records = data[i].getRecords();
        for (let j = 0; j < records.length; j++) {
          if (records[j].getType() === uniformTypeDescriptor.UniformDataType.PLAIN_TEXT) {
            let text = records[j] as unifiedDataChannel.PlainText;
            console.info(`${i + 1}.${text.textContent}`);
          }
        }
      }
    } else {
      console.error(`Failed to query data. code is ${err.code},message is ${err.message} `);
    }
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Query data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.queryData

queryData(options: Options): Promise<Array<UnifiedData>>

Queries data in the UDMF public data channel. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Both the key and intention are optional, and the return value varies depending on the parameters passed in.

Return value

Type	Description
Promise<Array<UnifiedData>>	Promise used to return the result. If only the key is specified in options, the data corresponding to the key is returned. If only the intention is specified in options, all data in the intention is returned. If both intention and key are specified, the intersection of the two is returned, which is the result obtained when only key is specified. If there is no intersection between the specified intention and key, an error object is returned.

Type

Description

Promise<Array<UnifiedData>>

Promise used to return the result.
If only the key is specified in options, the data corresponding to the key is returned.
If only the intention is specified in options, all data in the intention is returned.
If both intention and key are specified, the intersection of the two is returned, which is the result obtained when only key is specified. If there is no intersection between the specified intention and key, an error object is returned.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import uniformTypeDescriptor from '@ohos.data.uniformTypeDescriptor';
import { BusinessError } from '@ohos.base';

let options: unifiedDataChannel.Options = {
  key: 'udmf://DataHub/com.ohos.test/0123456789'
};

try {
  unifiedDataChannel.queryData(options).then((data) => {
    console.info(`Succeeded in querying data. size = ${data.length}`);
    for (let i = 0; i < data.length; i++) {
      let records = data[i].getRecords();
      for (let j = 0; j < records.length; j++) {
        if (records[j].getType() === uniformTypeDescriptor.UniformDataType.PLAIN_TEXT) {
          let text = records[j] as unifiedDataChannel.PlainText;
          console.info(`${i + 1}.${text.textContent}`);
        }
      }
    }
  }).catch((err: BusinessError) => {
    console.error(`Failed to query data. code is ${err.code},message is ${err.message} `);
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Query data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.deleteData

deleteData(options: Options, callback: AsyncCallback<Array<UnifiedData>>): void

Deletes data from the UDMF public data channel. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Both the key and intention are optional, and the return value varies depending on the parameters passed in.
callback	AsyncCallback<Array<UnifiedData>>	Yes	Callback invoked to return the data deleted. If only the key is specified in options, the data corresponding to the key deleted is returned. If only the intention is specified in options, all data in the intention deleted is returned. If both intention and key are specified, the intersection of the two deleted is returned. If there is no intersection between the two, an error object is returned.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import uniformTypeDescriptor from '@ohos.data.uniformTypeDescriptor';
import { BusinessError } from '@ohos.base';

let options: unifiedDataChannel.Options = {
  intention: unifiedDataChannel.Intention.DATA_HUB
};

try {
  unifiedDataChannel.deleteData(options, (err, data) => {
    if (err === undefined) {
      console.info(`Succeeded in deleting data. size = ${data.length}`);
      for (let i = 0; i < data.length; i++) {
        let records = data[i].getRecords();
        for (let j = 0; j < records.length; j++) {
          if (records[j].getType() === uniformTypeDescriptor.UniformDataType.PLAIN_TEXT) {
            let text = records[j] as unifiedDataChannel.PlainText;
            console.info(`${i + 1}.${text.textContent}`);
          }
        }
      }
    } else {
      console.error(`Failed to delete data. code is ${err.code},message is ${err.message} `);
    }
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Delete data throws an exception. code is ${error.code},message is ${error.message} `);
}

unifiedDataChannel.deleteData

deleteData(options: Options): Promise<Array<UnifiedData>>

Deletes data from the UDMF public data channel. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

Parameters

Name	Type	Mandatory	Description
options	Options	Yes	Configuration parameters. Both the key and intention are optional, and the return value varies depending on the parameters passed in.

Return value

Type	Description
Promise<Array<UnifiedData>>	Promise used to return the data deleted. If only the key is specified in options, the data corresponding to the key deleted is returned. If only the intention is specified in options, all data in the intention deleted is returned. If both intention and key are specified, the intersection of the two deleted is returned. If there is no intersection between the two, an error object is returned.

Type

Description

Promise<Array<UnifiedData>>

Promise used to return the data deleted.
If only the key is specified in options, the data corresponding to the key deleted is returned.
If only the intention is specified in options, all data in the intention deleted is returned.
If both intention and key are specified, the intersection of the two deleted is returned. If there is no intersection between the two, an error object is returned.

Example

import unifiedDataChannel from '@ohos.data.unifiedDataChannel';
import uniformTypeDescriptor from '@ohos.data.uniformTypeDescriptor';
import { BusinessError } from '@ohos.base';

let options: unifiedDataChannel.Options = {
  key: 'udmf://DataHub/com.ohos.test/0123456789'
};

try {
  unifiedDataChannel.deleteData(options).then((data) => {
    console.info(`Succeeded in deleting data. size = ${data.length}`);
    for (let i = 0; i < data.length; i++) {
      let records = data[i].getRecords();
      for (let j = 0; j < records.length; j++) {
        if (records[j].getType() === uniformTypeDescriptor.UniformDataType.PLAIN_TEXT) {
          let text = records[j] as unifiedDataChannel.PlainText;
          console.info(`${i + 1}.${text.textContent}`);
        }
      }
    }
  }).catch((err: BusinessError) => {
    console.error(`Failed to delete data. code is ${err.code},message is ${err.message} `);
  });
} catch (e) {
  let error: BusinessError = e as BusinessError;
  console.error(`Query data throws an exception. code is ${error.code},message is ${error.message} `);
}

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@ohos.data.unifiedDataChannel (Unified Data Channel)

Modules to Import

UnifiedData

constructor

addRecord

getRecords

Summary

UnifiedRecord

getType

Text

PlainText

Hyperlink

HTML

File

Image

Video

Audio

Folder

SystemDefinedRecord

SystemDefinedForm

SystemDefinedAppItem

SystemDefinedPixelMap

ApplicationDefinedRecord

Intention

Options

unifiedDataChannel.insertData

unifiedDataChannel.insertData

unifiedDataChannel.updateData

unifiedDataChannel.updateData

unifiedDataChannel.queryData

unifiedDataChannel.queryData

unifiedDataChannel.deleteData

unifiedDataChannel.deleteData

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@ohos.data.unifiedDataChannel (Unified Data Channel)

Modules to Import

UnifiedData

constructor

addRecord

getRecords

Summary

UnifiedRecord

getType

Text

PlainText

Hyperlink

HTML

File

Image

Video

Audio

Folder

SystemDefinedRecord

SystemDefinedForm

SystemDefinedAppItem

SystemDefinedPixelMap

ApplicationDefinedRecord

Intention

Options

unifiedDataChannel.insertData

unifiedDataChannel.insertData

unifiedDataChannel.updateData

unifiedDataChannel.updateData

unifiedDataChannel.queryData

unifiedDataChannel.queryData

unifiedDataChannel.deleteData

unifiedDataChannel.deleteData

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