AndroidManifest.xml

<!--maxSdkVersion=30適配到Android11 -->
<uses-permission
? ? android:name="android.permission.BLUETOOTH"
? ? android:maxSdkVersion="30" />
<uses-permission
? ? android:name="android.permission.BLUETOOTH_ADMIN"
? ? android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<!--Android12新增藍(lán)牙權(quán)限 -->
<!-- Android 12在不申請定位權(quán)限時，必須加上android:usesPermissionFlags="neverForLocation"，否則搜不到設(shè)備 -->
<uses-permission android:name="android.permission.BLUETOOTH_SCAN"
? ? ? ? android:usesPermissionFlags="neverForLocation"
        tools:targetApi="s" />
<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

代碼

//獲取藍(lán)牙適配器
public static BluetoothAdapter mBluetoothAdapter = null;
? ? //藍(lán)牙狀態(tài)監(jiān)聽廣播
    public class BlueToothReceiver extends BroadcastReceiver {
        @Override
        public void onReceive(Context context, Intent intent) {
            switch (intent.getAction()) {
                case BluetoothAdapter.ACTION_STATE_CHANGED:
                    int blueState = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, 0);
                    switch (blueState) {
                        case BluetoothAdapter.STATE_TURNING_ON:
                            Log.e("onReceive", "---------藍(lán)牙正在打開中");
                            break;
                        case BluetoothAdapter.STATE_ON:
                            Log.e("onReceive", "---------藍(lán)牙已經(jīng)打開");
                            mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
                            break;
                        case BluetoothAdapter.STATE_TURNING_OFF:
                            Log.e("onReceive", "---------藍(lán)牙正在關(guān)閉中");
                            break;
                        case BluetoothAdapter.STATE_OFF:
                            Log.e("onReceive", "---------藍(lán)牙已經(jīng)關(guān)閉");
                            break;
                    }
                    break;
            }
        }
    }
? ? private IntentFilter makeFilter() {
        IntentFilter filter = new IntentFilter();
        filter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);
        return filter;
    }
? ? //Android12藍(lán)牙權(quán)限申請
    private boolean bluePermission(){
? ? //compileSdkVersion項目中編譯SDK版本大于30申請以下權(quán)限可使用
? ? //Manifest.permission.BLUETOOTH_SCAN、Manifest.permission.BLUETOOTH_ADVERTISE、Manifest.permission.BLUETOOTH_CONNECT
? ? //若小于30可以直接使用權(quán)限對應(yīng)的字符串
        if (Build.VERSION.SDK_INT>30){
            if (ContextCompat.checkSelfPermission(this,
                    "android.permission.BLUETOOTH_SCAN")
                    != PERMISSION_GRANTED
                    || ContextCompat.checkSelfPermission(this,
                    "android.permission.BLUETOOTH_ADVERTISE")
                    != PERMISSION_GRANTED
                    || ContextCompat.checkSelfPermission(this,
                    "android.permission.BLUETOOTH_CONNECT")
                    != PERMISSION_GRANTED){
                ActivityCompat.requestPermissions(this,new String[]{
                                "android.permission.BLUETOOTH_SCAN",
                                "android.permission.BLUETOOTH_ADVERTISE",
                                "android.permission.BLUETOOTH_CONNECT"}, 1);
                return false;
            }
        }
        return true;
    }
? ? private void openBlueTooth(){
        if (bluePermission())
            mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        else
            return;
        BlueToothReceiver btlr = new BlueToothReceiver();
        this.registerReceiver(btlr, makeFilter());
? ? ? ? if (!mBluetoothAdapter.isEnabled()) {// 判斷是否打開藍(lán)牙
            showHandlerToast("請先開啟藍(lán)牙!");
            //彈出對話框提示用戶是后打開
            Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            //startActivityForResult(intent, SEARCH_CODE);
            // 不做提示，強行打開
            mBluetoothAdapter.enable();
        }
? ? }

說明：

必須按照這兩步申請藍(lán)牙權(quán)限，首先在androidManifest.xml中配置藍(lán)牙權(quán)限，Android11及以下android.permission.BLUETOOTH、android.permission.BLUETOOTH_ADMIN申請這兩個，Android12中藍(lán)牙權(quán)限進(jìn)行新增android.permission.BLUETOOTH_SCAN、android.permission.BLUETOOTH_ADVERTISE、android.permission.BLUETOOTH_CONNECT使用這三個；其次在代碼中需要動態(tài)申請Android12的藍(lán)牙權(quán)限，測試發(fā)現(xiàn)Android12中動態(tài)申請權(quán)限后則藍(lán)牙直接開啟，通過對藍(lán)牙狀態(tài)的監(jiān)聽獲取藍(lán)牙適配器：mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

注意：不管是Android12還是Android12以下不打開藍(lán)牙都是無法獲取藍(lán)牙適配器：mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();打開藍(lán)牙則可以獲取到藍(lán)牙適配器，但若沒有申請藍(lán)牙所需權(quán)限，藍(lán)牙功能也是無法使用?。?！二者缺一不可文章來源地址http://www.zghlxwxcb.cn/news/detail-503673.html