Using Deep Linking for Application Redirection
In Deep Linking, the system, based on the passed-in URI, searches for the application that meets the conditions from the locally installed applications and starts that application. If multiple applications are matched, a dialog box is displayed for users to select one of them.
Working Principles
Deep Linking searches for an application based on the URI matching rules in implicit Want mechanism and starts the matching application. For details about the URI matching rules of implicit Want, see Matching Rules of uri.
Procedure for the Target Application
Configuring the module.json5 File
To be accessed by other applications, an application must configure the skills field of the module.json5 file.
NOTE
By default, the skills field contains a skill object, which is used to identify the application entry. Application redirection links should not be configured in this object. Instead, separate skill objects should be used. If there are multiple redirection scenarios, create different skill objects under skills. Otherwise, the configuration does not take effect.
In Deep Linking, the value of scheme should not start with ohos. Generally, it should also not use values like https, http, or file, which are already in use by system applications, as this may cause the link to match with the corresponding system application.
A configuration example is as follows:
{
"module": {
// ···
"abilities": [
// ···
{
// ···
"skills": [
{
"entities": [
"entity.system.home"
],
"actions": [
"ohos.want.action.home"
]
},
{
"actions": [
// actions cannot be empty. Otherwise, matching the target application fails.
"ohos.want.action.viewData"
],
"uris": [
{
// scheme is mandatory and can be customized. The following uses link as an example. Replace it with the actual scheme.
"scheme": "link",
"host": "www.example.com"
}
]
} // Add a skill object for redirection. If there are multiple redirection scenarios, create multiple skill objects.
]
},
// ···
],
// ···
}
}
Obtaining and Parsing the Link Passed by the Caller
In the onCreate() or onNewWant() lifecycle callback of the UIAbility of the target application, obtain and parse the link passed by the caller.
// DeepAbility.ets is used as an example.
import { AbilityConstant, UIAbility, Want } from '@kit.AbilityKit';
import { url } from '@kit.ArkTS';
const DOMAIN = 0x0000;
export default class DeepAbility extends UIAbility {
onCreate(want: Want, launchParam: AbilityConstant.LaunchParam): void {
// Obtain the input link information from want.
// For example, the input URL is link://www.example.com/programs?action=showall.
let uri = want?.uri;
if (uri) {
// Parse the query parameter from the link. You can perform subsequent processing based on service requirements.
let urlObject = url.URL.parseURL(want?.uri);
let action = urlObject.params.get('action');
// For example, if action is set to showall, all programs are displayed.
if (action === 'showall') {
// ···
}
}
}
// ···
}
Implementing Application Redirection (Required for the Caller Application)
The following uses three cases to describe how to use openLink() and startAbility() to implement application redirection and how to implement application redirection in the Web component.
Using openLink to Implement Application Redirection
Pass in the URL of the target application into link of openLink, and set appLinkingOnly in the options field to false.
The sample code is as follows:
import { common, OpenLinkOptions } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
const TAG: string = '[UIAbilityComponentsOpenLink]';
const DOMAIN_NUMBER: number = 0xFF00;
@Entry
@Component
struct DeepOpenLinkIndex {
build() {
Button('start link', { type: ButtonType.Capsule, stateEffect: true })
.width('87%')
.height('5%')
.margin({ bottom: '12vp' })
.onClick(() => {
let context = this.getUIContext().getHostContext() as common.UIAbilityContext;
let link: string = 'link://www.example.com'; // Use the actual application link.
let openLinkOptions: OpenLinkOptions = {
appLinkingOnly: false
};
try {
context.openLink(link, openLinkOptions)
.then(() => {
hilog.info(DOMAIN_NUMBER, TAG, 'openLink success.');
}).catch((err: BusinessError) => {
hilog.error(DOMAIN_NUMBER, TAG, `openLink failed. Code is ${err.code}, message is ${err.message}`);
});
} catch (paramError) {
hilog.error(DOMAIN_NUMBER, TAG, `Failed to start link. Code is ${paramError.code}, message is ${paramError.message}`);
}
})
}
}
Using startAbility() to Implement Application Redirection
Pass in the target application's link into want of startAbility, which then uses implicit Want to trigger application redirection.
The sample code is as follows:
import { common, Want } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
const TAG: string = '[UIAbilityComponentsOpenLink]';
const DOMAIN_NUMBER: number = 0xFF00;
@Entry
@Component
struct DeepStartIndex {
build() {
Button('start ability', { type: ButtonType.Capsule, stateEffect: true })
.width('87%')
.height('5%')
.margin({ bottom: '12vp' })
.onClick(() => {
let context = this.getUIContext().getHostContext() as common.UIAbilityContext;
let want: Want = {
uri: 'link://www.example.com' // Use the actual application link.
};
try {
context.startAbility(want).then(() => {
hilog.info(DOMAIN_NUMBER, TAG, 'startAbility success.');
}).catch((err: BusinessError) => {
hilog.error(DOMAIN_NUMBER, TAG, `startAbility failed. Code is ${err.code}, message is ${err.message}`);
});
} catch (paramError) {
hilog.error(DOMAIN_NUMBER, TAG, `Failed to start ability. Code is ${paramError.code}, message is ${paramError.message}`);
}
})
}
}
Using the Web Component to Implement Application Redirection
You can use the Web component to implement application redirection in the callback function of onLoadIntercept.
The sample code is as follows:
// DeepWebIndex.ets
import { webview } from '@kit.ArkWeb';
import { BusinessError } from '@kit.BasicServicesKit';
import { common } from '@kit.AbilityKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
const DOMAIN_NUMBER = 0xF811;
const TAG = '[Sample_PullLinking]';
@Entry
@Component
struct DeepWebIndex {
controller: webview.WebviewController = new webview.WebviewController();
build() {
Column() {
Web({ src: $rawfile('index.html'), controller: this.controller })
.onLoadIntercept((event) => {
const url: string = event.data.getRequestUrl();
if (url === 'link://www.example.com') {
(this.getUIContext().getHostContext() as common.UIAbilityContext).openLink(url)
.then(() => {
hilog.info(DOMAIN_NUMBER, TAG, 'openLink success.');
}).catch((err: BusinessError) => {
hilog.error(DOMAIN_NUMBER, TAG, `openLink failed, err: ${JSON.stringify(err)}.`);
});
return true;
}
// If true is returned, the loading is blocked. Otherwise, the loading is allowed.
return false;
})
}
}
}
Frontend page code:
// index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
</head>
<body>
<h1>Hello World</h1>
<!--Method 1: Bind window.open to implement redirection.-->;
<button class="doOpenLink" onclick="doOpenLink()">Redirect to application 1</button>
<!--Method 2: Use a hyperlink for redirection.-->;
<a href="link://www.example.com">Redirect to application 2</a>
</body>
</html>
<script>
function doOpenLink() {
window.open("link://www.example.com")
}
</script>