随笔

import android.Manifest
import android.content.Context
import android.content.pm.PackageManager
import android.os.Build
import androidx.activity.result.contract.ActivityResultContracts
import androidx.core.app.ActivityCompat
import androidx.fragment.app.Fragment

class MyFragment : Fragment() {

    companion object {
        val TAG: String = MyFragment::class.java.simpleName
        var PERMISSIONS = arrayOf(
            Manifest.permission.CAMERA,
            Manifest.permission.READ_EXTERNAL_STORAGE,
            Manifest.permission.WRITE_EXTERNAL_STORAGE
        )
    }

    private val permReqLauncher =
        registerForActivityResult(ActivityResultContracts.RequestMultiplePermissions()) { permissions ->
            val granted = permissions.entries.all {
                it.value == true
            }
            if (granted) {
                displayCameraFragment()
            }
        }

    private fun takePhoto() {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
            displayCameraFragment()
        }
        activity?.let {
            if (hasPermissions(activity as Context, PERMISSIONS)) {
                displayCameraFragment()
            } else {
                permReqLauncher.launch(
                    PERMISSIONS
                )
            }
        }
    }

    // util method
    private fun hasPermissions(context: Context, permissions: Array<String>): Boolean =
        permissions.all {
            ActivityCompat.checkSelfPermission(context, it) == PackageManager.PERMISSION_GRANTED
        }

    private fun displayCameraFragment() {
        // open camera fragment
    }
}