Permisos de tiempo de ejecución de Android usando Jetpack Compose

Hay muchas funciones dentro de las aplicaciones de Android que requieren que el usuario otorgue permisos. Para otorgar estos permisos durante el tiempo de ejecución, los permisos de tiempo de ejecución se utilizan dentro de las aplicaciones de Android. Estos permisos se solicitan cuando el usuario desea utilizar alguna característica específica. Antes de usar esa función, se solicita permiso al usuario. Este tipo de permiso solicitado durante el tiempo de ejecución se denomina permiso de tiempo de ejecución. En este artículo, veremos cómo usar los permisos de tiempo de ejecución en aplicaciones de Android usando Jetpack Compose . 

Implementación paso a paso

Paso 1: crea un nuevo proyecto en Android Studio

Para crear un nuevo proyecto en Android Studio, consulte Cómo crear/iniciar un nuevo proyecto en Android Studio . Al elegir la plantilla, seleccione Actividad de composición vacía . Si no encuentra esta plantilla, intente actualizar Android Studio a la última versión. Demostramos la aplicación en Kotlin, así que asegúrese de seleccionar Kotlin como idioma principal al crear un nuevo proyecto.

Paso 2: Agregar un nuevo color en el archivo Color.kt

Vaya a aplicación>java>nombre del paquete de su aplicación>ui.theme>archivo Color.kt y agregue el código a continuación. Se agregan comentarios en el código para conocer en detalle. 

package com.example.newcanaryproject.ui.theme
 
import androidx.compose.ui.graphics.Color
 
val Purple200 = Color(0xFF0F9D58)
val Purple500 = Color(0xFF0F9D58)
val Purple700 = Color(0xFF3700B3)
val Teal200 = Color(0xFF03DAC5)
 
// on below line we are adding different colors.
val greenColor = Color(0xFF0F9D58)

Paso 3: Agregar permiso en el archivo AndroidManifest.xml

Vaya a aplicación>manifiesto>AndroidManifest.xml y agregue los siguientes permisos en la etiqueta del manifiesto. 

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

Paso 4: trabajar con el archivo MainActivity.kt

Vaya al archivo MainActivity.kt y consulte el siguiente código. A continuación se muestra el código del archivo MainActivity.kt . Se agregan comentarios dentro del código para comprender el código con más detalle.

package com.example.newcanaryproject
 
import android.app.Activity
import android.content.Context
import android.content.Intent
import android.Manifest
import android.content.SharedPreferences
import android.content.pm.PackageManager
import android.net.Uri
import android.os.Bundle
import android.util.Log
import android.widget.Toast
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.*
import androidx.compose.material.*
import androidx.compose.material.icons.Icons
import androidx.compose.material.icons.filled.Email
import androidx.compose.material.icons.filled.Password
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.text.font.FontFamily
import androidx.compose.ui.text.font.FontStyle
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.text.input.PasswordVisualTransformation
import androidx.compose.ui.text.input.TextFieldValue
import androidx.compose.ui.text.style.TextAlign
import androidx.compose.ui.unit.*
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import com.example.newcanaryproject.ui.theme.*
 
class MainActivity : ComponentActivity() {
 
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            NewCanaryProjectTheme {
                // on below line we are specifying background
                // color for our application
                Surface(
                    // on below line we are specifying
                    // modifier and color for our app
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colors.background
                ) {
 
                    // on below line we are specifying theme as scaffold.
                    Scaffold(
 
                        // in scaffold we are specifying top bar.
                        topBar = {
 
                            // inside top bar we are specifying background color.
                            TopAppBar(backgroundColor = greenColor,
 
                                // along with that we are specifying
                                // title for our top bar.
                                title = {
 
                                    // in the top bar we are specifying tile as a text
                                    Text(
 
                                        // on below line we are specifying
                                        // text to display in top app bar.
                                        text = "Runtime permissions",
 
                                        // on below line we are specifying modifier
                                        // to fill max width.
                                        modifier = Modifier.fillMaxWidth(),
 
                                        // on below line we are specifying
                                        // text alignment.
                                        textAlign = TextAlign.Center,
 
                                        // on below line we are specifying
                                        // color for our text.
                                        color = Color.White
                                    )
                                }
                            )
                        }
                    ) {
                        // on below line we are calling session
                        // management method and passing
                        // shared preferences to it.
                        runtimePermissions()
                    }
                }
            }
        }
    }
 
    // on below line we are calling on
    // request permission result method.
    override fun onRequestPermissionsResult(
        requestCode: Int,
        permissions: Array<out String>,
        grantResults: IntArray
    ) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
 
        // in this method we are checking if the request code
        // which we have passed 101 is same.
        if (requestCode == 101) {
            // if request code is 101 and permissions are granted.
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
 
                // on below line we are displaying a toast message.
                Toast.makeText(this, "Storage permission granted", Toast.LENGTH_SHORT).show()
            } else {
                // on below line we are displaying a toast message.
                Toast.makeText(this, "Storage permission denied", Toast.LENGTH_SHORT).show()
            }
        }
    }
}
 
// on below line we are creating a
// method as run time permission.
@Composable
fun runtimePermissions() {
     
    // on below line we are creating a variable
    // for activity and initializing it.
    val activity = (LocalContext.current as? Activity)
 
    // on below line we are creating a column.
    Column(
 
        // on below line we are adding modifier to
        // add max width, max size and max height
        // for our column.
        modifier = Modifier
            .fillMaxWidth()
            .fillMaxHeight()
            .fillMaxSize(),
 
        // on below line we are adding horizontal alignment.
        horizontalAlignment = Alignment.CenterHorizontally,
 
        // on below line we are adding
        // vertical arrangement to center.
        verticalArrangement = Arrangement.Center
    ) {
        // on below line we are adding a text
        Text(
            // in this we are specifying text as
            // Runtime permissions in android
            // on below line.
            text = "Runtime permissions in Android",
 
            // on below line we are adding font style.
            fontStyle = FontStyle.Normal,
 
            // on below line we are adding
            // font weight on below line as bold.
            fontWeight = FontWeight.Bold,
 
            // on below line we are adding
            // green color to our text
            color = greenColor,
 
            // on below line we are adding
            // font size to our text.
            fontSize = 20.sp
        )
 
        // on below line we are adding spacer between text and button.
        Spacer(modifier = Modifier.height(50.dp))
 
        // on below line we are creating a button
        Button(
            // on below line we are adding a modifier for our
            // button and adding a max width and padding to it.
            modifier = Modifier
                .fillMaxWidth()
                .padding(20.dp),
 
            // on below line we are adding on click for our button.
            onClick = {
                // in the on click method we are calling check permission
                // method to check the permission
                checkPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE, 101, activity!!)
            }) {
            // on below line we are creating a text for our button on below line and adding a padding to it.
            Text(modifier = Modifier.padding(6.dp), text = "Request Storage permission")
        }
    }
}
 
// on below line we are creating a check permission method to check the permissions.
fun checkPermission(permission: String, requestCode: Int, activity: Activity) {
    // on below line we are checking if the permission is denied.
    if (ContextCompat.checkSelfPermission(
            activity,
            permission
        ) == PackageManager.PERMISSION_DENIED
    ) {
        // if the permission is denied we are calling
        // request permission method to request permissions.
        ActivityCompat.requestPermissions(activity, arrayOf(permission), requestCode)
    } else {
        // this method will be called if the permissions are already granted.
        // On below line we are displaying a toast message if permissions are granted.
        Toast.makeText(activity, "Permission already granted..", Toast.LENGTH_SHORT).show()
    }
}

Ahora ejecute su aplicación para ver el resultado. 

Producción: