@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 definitions for uniform 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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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 service widget data defined by the system, which is a child class of SystemDefinedRecord.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

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 data of the home screen icon defined by the system. It is a child class of SystemDefinedRecord.

System capability: SystemCapability.DistributedDataManager.UDMF.Core

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

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

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

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

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

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

Return 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 = {
  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

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

Return 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

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

Return value

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

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

Return value

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} `);
}