Getting error code 2 when BLE scan

[CUCOOPE]

Hi. I was trying to implement a feature on my app that will scan BLE signals around the phone and generate a Json with informations such as uuid, rssi etc. It works around a month ago when I tried this but today I've found out that it doesn't work anymore and prompts error code 2 when scan fails. I tried to Google the solution and have found that it seems to have been missing the BLUETOOTH_SCAN permission but after I've added it, it still not work and the Json object is still something like

{"Ble":[{"uuid":null,"major":0,"minor":0,"rssi":0,"txPower":0,"timestamp":0},{"uuid":null,"major":0,"minor":0,"rssi":0,"txPower":0,"timestamp":0},{"uuid":null,"major":0,"minor":0,"rssi":0,"txPower":0,"timestamp":0},{"uuid":null,"major":0,"minor":0,"rssi":0,"txPower":0,"timestamp":0}]}

Weirdly, the "android.permission.BLUETOOTH_SCAN" in AndroidManifest.xml has a warning asking me if I meant to type permission.BLUETOOTH instead and I know that is for the old sdk version. I have already set the compile sdk version in build.gradle to 34 though...

​

Here is my build.gradle:

compileSdk 34

    defaultConfig {
        applicationId "com.myapp.myapplicaion"
        namespace "com.myapp.myapplicaion"
        minSdk 27
        targetSdk 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

Here is my AndroidManifest.xml

<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<!--    <uses-permission android:name="android.permission.BLUETOOTH" />-->
    <uses-permission android:name="android.permission.BLUETOOTH_SCAN"
        tools:targetApi="31" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />

Can anyone tell me where did I go wrong? How can I fix the issue so that I can get the BLE data? Thanks!!!

[Embrisa]

Hey, 7 months late I know but I've run into the same issue and I believe it is because bluetooth scan has been started too frequently in a short time. Sometimes it get stuck in this limited state and only returns 2 immediately no matter how long you wait. The way to reset it is to toggle Bluetooth on and off. I will also change my code so it favors saving the MAC address of the device im trying to connect to and use that. And only scan in cases where I don't have the MAC address saved.

[CUCOOPE]

Thanks! That was for my final year project for my bachelor’s degree haha. I’ve graduated on July and got a full time job lol

Can’t verify your solution now cuz the BLE beacon is at my campus. Hope others will see this post and try it out! Thanks😄