How come mini programs support opening mobile apps?

According to the article "Mini Programs Support Opening Mobile Apps" published by Apple's official WeChat public platform, Mini Programs have added two new functions:

• Support opening mobile applications
• Title bar area is open for customization

The second function is that developers can customize the color style of the mini-program menu bar and customize the title area outside the mini-program menu according to their needs, such as setting the color of the title area. Here we mainly introduce the function of supporting opening mobile applications.

Support opening mobile applications

At first glance, it seems a bit like a headline party, but does it support opening mobile apps?

• What makes me think is that I can use applet to open any mobile application? (The answer is no)
• So can I open my own app? (The answer is limited)
• Can I open the browser that comes with the system? (The answer is no)
• Can I open third-party mobile apps? (The answer is no)

In fact, there is a hard requirement for opening mobile apps from mini programs: when users access pages shared from mobile apps to mini programs, they can open the source app. Let’s further explain this requirement.

Most programs have WeChat sharing function. What we often do is to share a picture, a text or a URL link. We can share it with friends (including groups), Moments or add it to personal collections, as follows:

We can also share mini-programs, as shown in the figure:

The above is a small program shared to WeChat by a ticket grabbing software (Zhixing). Friends can click on the small program to help speed up. According to the official article, if there is a button in the small program shared to WeChat, the implementation is as follows:

 <button open -type= "launchApp" app-parameter= "wechat" binderror= "launchAppError" >Open APP</button>

Then when you click this button, the source app will be opened. In other cases, it cannot be opened. Here is a diagram showing whether a mobile app can be opened:

Here, the mini program gives a concept of scene value. Only the mini program with a scene value of 1036 (and a status value of true or false, which determines whether the APP can be opened. The scene value is 1036 and the status value is true) can open the source APP. That is, the mini program cannot open any app, but can only jump back to the APP that shared the mini program card. The official document also explains this logo:

During the life cycle of the mini program, the initial value of this state is false, and it will change each time the mini program is opened (whether it is started or switched to the foreground):

1. When the mini program is opened from 1036 (App Share Message Card), this state is set to true.
2. When the mini program is opened from scenario 1089 (pull down from the main WeChat chat interface) or 1090 (long press the menu in the upper right corner of the mini program to call out the recent usage history), the state remains unchanged, that is, the value of the state when the mini program was last opened is maintained.
3. When the applet is opened from a scene other than 1036/1089/1090, this state is set to false.

Regarding the second point, 1089 and 1090, my understanding is that the mini program is similar to the mobile app. It is not closed, but in the background. Therefore, 1089 and 1090 only call the mini program to the foreground, so the mini program status remains unchanged. If the status is true, the mobile app can also be opened.

The above is an introduction to opening mobile applications with mini programs. Next, let’s take a look at the specific code implementation.

Code to implement the shared applet to open the mobile app (iOS version, Android is similar)

The first thing to do is to create a new project and then integrate WeChat sharing. For details on how to integrate, please refer to the official website integration document. After integration, add a button to the page and trigger the implementation as follows:

 - (IBAction)openSmallProgramAction:(id)sender {
 //Share the implementation of the applet
    WXMiniProgramObject *wxMiniObject = [WXMiniProgramObject object];
    wxMiniObject.userName = @ "gh_*************" ;
    wxMiniObject.path = @ "pages/index/index" ;
 //
    WXMediaMessage *message = [WXMediaMessage message];
 message.title = @ "I am a mini program" ;
 message.description = @ "I am a small program used to test opening the App" ;
    message.mediaObject = wxMiniObject; 
     
    SendMessageToWXReq *req = [[SendMessageToWXReq alloc] init];
 req.message = message;
    req.scene = WXSceneSession;
 [WXApi sendReq:req];
 //Original sharing implementation
 // SendMessageToWXReq *req = [[SendMessageToWXReq alloc] init];
 // req.text = @ "Shared content" ;
 // req.bText = YES;
 // req.scene = WXSceneSession;
 // [WXApi sendReq:req];
 }

Can all apps share mini programs using the above implementation method? The answer is no. According to the official document:

• The mobile app sharing function supports mini-program type sharing, requiring the app that initiates the sharing and the mini-program to belong to the same WeChat Open Platform account. It supports sharing mini-program type messages to friend conversations, but does not support "Share to Moments" and "Collect".

In other words, there are restrictions on sharing mini programs:

• The App and Mini Program that initiate the sharing belong to the same WeChat Open Platform account
• Only supports sharing mini-program type messages to friend sessions (SendMessageToWXReq's scence only supports WXSceneSession)

After testing, an account cannot be registered for both WeChat Open Platform and WeChat Public Platform at the same time. In other words, if your account is registered for WeChat Open Platform, then the account cannot be registered for WeChat Public Platform again.

• The WeChat open platform is for mobile apps.
• The WeChat public platform contains mini-programs.

What the official WeChat Open Platform account means is that there are both APPs and Mini Programs under one account (because Mini Programs are developed on WeChat Public Platform). After opening the WeChat Open Platform page, the first item is easy to understand:

If you want to share a Mini Program in a mobile app, you must bind the WeChat Mini Program to the WeChat Open Platform account where the app is located, so that you can share the Mini Program in the app. This is what the official statement means that the app and the Mini Program belong to the same WeChat Open Platform account.

So how does the APP know which mini program to share? Or how is the APP connected to the mini program?

This depends on the code above (assuming you put the mini program and APP under the same open platform account), which contains a line:

 wxMiniObject.userName = @ "gh_*************" ;

The userName is the userName of the mini program. You can log in to the WeChat Official Account Platform | Mini Program, and then check it in Settings -> Basic Settings. There is an original id, which is the userName of the mini program.

In this way, you will associate the sharing of the APP with the mini program.

There is another question: How can the shared mini program open the specified page?

This requires looking at another line of code:

 wxMiniObject.path = @ "pages/index/index" ;

You need to set the path of the mini program. The page of this path is the page that opens when you click on the shared mini program. Here is a picture of the mini program development tool:

Pages refers to pages. For example, the pages folder in the figure above contains three pages: detail, index, and logs. Among them:

• index: refers to the credit card list page.
• detail: refers to the detail page entered by clicking an item in the list.
• logs: log page

So if you want to jump to the detail page, you should write "pages/detail/detail" when setting the path of wxMiniObject. In this way, you can click on the shared applet to enter the specified page (if the page requires parameters, you must also pass them when sharing).

• wxml: equivalent to html
• wxss: equivalent to css

Here the suffix is ​​actually defined by the WeChat applet itself.

At this time, the scene value of the mini program you shared is 1036, and the status is true. If there is a button with open-type "launchApp" in your mini program, you will jump back to your mobile app by clicking the button. If you want to send content back to the app, you can set app-parameter. Like this small button:

 <button open -type= "launchApp" app-parameter= "wechat" binderror= "launchAppError" >Open APP</button>

At this point, I think you should have a general understanding of how mini programs support opening mobile apps.

Summarize

Mini Programs do not support opening all mobile apps. Even if the mobile apps and Mini Programs are under the same WeChat Open Platform account, the Mini Programs may not be able to be opened. It depends on the specific scenario.

Outlook

The fact that mini programs can jump to mobile apps is a big improvement. In the future, mini programs will be able to be opened directly from apps, not just by sharing. In the future, we may be able to directly open a mini program by clicking a button in a mobile app, and then return to the mobile app after the mini program operation is completed. (For example, for WeChat payment, you can jump from the mobile app to the mini program to make WeChat payment, and return to the mobile app directly after the payment is successful)

The fact that mini programs can jump to mobile apps is a big improvement. In the future, mini programs will be able to be opened directly from apps, not just by sharing. In the future, we may be able to directly open a mini program by clicking a button in a mobile app, and then return to the mobile app after the mini program operation is completed. (For example, for WeChat payment, you can jump from the mobile app to the mini program to make WeChat payment, and return to the mobile app directly after the payment is successful)