App-to-App Message Communications

This API is used to establish the communications channel between your phone app and wearable app, to receive and send packet messages and files customized by your app. This makes the interaction between the phone app and its wearable counterpart a full-fledged reality, providing the distributed scenarios and experience for your users. For example, a phone app sends an audio file to the wearable app, to play music on the wearable app; the phone app sends a pause command, to pause the music playback and the like on the wearable device.

Before sending or receiving messages, apply for the DEVICE_MANAGER permission from the user on the phone (by referring to Requesting User Authorization), otherwise you may not be able to call the corresponding API.

If the phone app is able to send messages, the wearable app must support receiving these messages.

• JS: Receiving P2P Messages or Files from Your Phone App
• Java: Receiving P2P Messages or Files from Your Phone App

1. Refer to Querying Available Wearable Devices to obtain the paired device list and select the device for communications.
2. Create a WESIdentityInfo object for the message sender, and specify the phone app bundle name and fingerprint. The fingerprint is used to verify the app information on the watch side. iOS apps do not have fingerprint information. You can enter any text as the fingerprint.
3. Create a WESIdentityInfo object for the message recipient, and specify the wearable app bundle name and fingerprint.

4. Create a WESP2PMessage object to construct the message to be sent.
5. Create a WESP2PData object to configure whether the message is of the TLV format.
6. Call the init method of TLVDataCmm to construct data. Create a TLVDataCmm object and construct data in TLV format.
7. Assign the data in TLV format to the message.
8. Call the getP2PClient method in HiWear to obtain the P2PClient object. Call the send method to send short messages from your phone app to the wearable app.
   • The callback parameter is used to return the message sending result.
   • The WearEngineServerErrorCode status parameter is used to return the sending result. WESErrorCodeCommSuccess indicates success, and other error codes indicate failure.

   @objc func sendDataBtnAction() {
       sendDataBtn.isSelected = !sendDataBtn.isSelected
       // Model conversion.
       let srcInfo = WESIdentityInfo()
       srcInfo.mPackageName = "XXXX" // Bundle name of the source app.
       srcInfo.mFingerPrint = "YYYY" // Fingerprint of the source app.
    
       let destInfo = WESIdentityInfo();
       destInfo.mPackageName = "XXXX" // Bundle name of the target app.
       destInfo.mFingerPrint = "YYYY" // Fingerprint of the target app.
    
       let message = WESP2PMessage();
       message.type = WESP2PMessageType.data;
    
       let wesP2PData = WESP2PData()
       wesP2PData.isTLVFormat = false
    
       let unitIsOpen = "XXXX" // Transmitted data.
       let tlv = TLVDataCmm.init(0, value: unitIsOpen.data(using: .utf8))
       let tlvData = tlv?.value ?? NSMutableData()
    
       let rootCmm = TLVDataCmm(type: 0x07, withLen: Int32(tlvData.count))
       let rootCmmData = rootCmm?.tlvToData() ?? Data()
    
       let tmpPayloadData = NSMutableData.init(data: rootCmmData)
       tmpPayloadData.append(tlvData as Data)
       wesP2PData.payloadData = tmpPayloadData.copy() as? Data
       message.p2pData = wesP2PData.copy() as? WESP2PData
       HiWear.getP2PClient().send(self.currentDevice, message: message, srcInfo: srcInfo, 
           destInfo: destInfo) { status, progress in
           if status == .WESErrorCodeCommSuccess {
               // P2P transmission is successful.
           } else {
               // P2P transmission fails. Error code: status.rawValue
           }
       }
   }

1. Refer to Querying Available Wearable Devices to obtain the paired device list and select the device for communications.
2. Create a WESIdentityInfo object for the message sender, and specify the wearable app bundle name and fingerprint.
3. Create a WESIdentityInfo object for the message recipient, and specify the phone app bundle name and fingerprint.
4. Call the getP2pClient method in HiWear to obtain the P2pClient object, and call registerReceiver to register a listener.

   let srcInfo = WESIdentityInfo()
   srcInfo.mPackageName = "XXXX" // Bundle name of the source app.
   srcInfo.mFingerPrint = "YYYY" // Fingerprint of the source app.
   let destInfo = WESIdentityInfo()
   destInfo.mPackageName = "XXXX" // Bundle name of the target app.
   destInfo.mFingerPrint = "YYYY" // Fingerprint of the target app.
   receiverCallback = {status, message in
       if status != .WESErrorCodeSuccess {
           // Fails to register the listener. Error code: status.rawValue
           return
       }
       if (status == .WESErrorCodeSuccess && message == nil) {
           // The listener is successfully registered. Package name: destInfo.mPackageName; fingerprint: destInfo.mFingerPrint
       }
       if (message != nil) {
           let response = message?.data
           let responseString :String = String.init(data: response ?? Data() , encoding: .utf8) ?? ""
           if (responseString.count > 0) {
               // Received P2P message: responseString
           } else {
               let string = message?.data.toHexString() ?? ""
               // Received P2P message: string
           }
       }}
   HiWear.getP2PClient().registerReceiver(currentDevice, srcInfo: srcInfo, destInfo: destInfo, receiverCallback: receiverCallback)

Unregister the listener for P2P messages.

1. Refer to Querying Available Wearable Devices to obtain the paired device list and select the device for communications.
2. Create a WESIdentityInfo object for the message sender, and specify the wearable app bundle name and fingerprint.
3. Create a WESIdentityInfo object for the message recipient, and specify the phone app bundle name and fingerprint.
4. Call the getP2pClient method in HiWear to obtain the P2pClient object, and call unRegisterReceiver to unregister the listener.

   let srcInfo = WESIdentityInfo()
   srcInfo.mPackageName = "XXXX" // Bundle name of the source app.
   srcInfo.mFingerPrint = "YYYY" // Fingerprint of the source app.
   let destInfo = WESIdentityInfo()
   destInfo.mPackageName = "XXXX" // Bundle name of the target app.
   destInfo.mFingerPrint = "YYYY" // Fingerprint of the target app.
   HiWear.getP2PClient().unRegisterReceiver(currentDevice, srcInfo: srcInfo, destInfo: destInfo) { status, message in
       if status != .WESErrorCodeSuccess {
           // Fails to unregister the listener. Error code: status.rawValue
           return
       }
       if (status == .WESErrorCodeSuccess) {
           // The listener is successfully unregistered. Package name: destInfo.mPackageName; fingerprint: destInfo.mFingerPrint
       }
   }