MainActivity.java Source code

Introduction

Here is the source code for MainActivity.java

Source

import android.Manifest;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    private final int REQUEST_PERMISSION_SEND_SMS = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    private boolean checkPermission(String permission) {
        int permissionCheck = ContextCompat.checkSelfPermission(this, permission);
        return (permissionCheck == PackageManager.PERMISSION_GRANTED);
    }

    private void showExplanation(String title, String message, final String permission,
            final int permissionRequestCode) {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle(title).setMessage(message).setPositiveButton(android.R.string.ok,
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        requestPermission(permission, permissionRequestCode);
                    }
                });
        builder.create().show();
    }

    private void requestPermission(String permissionName, int permissionRequestCode) {
        ActivityCompat.requestPermissions(this, new String[] { permissionName }, permissionRequestCode);
    }

    public void doSomething(View view) {
        if (!checkPermission(Manifest.permission.SEND_SMS)) {
            if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.SEND_SMS)) {
                showExplanation("Permission Needed", "Rationale", Manifest.permission.SEND_SMS,
                        REQUEST_PERMISSION_SEND_SMS);
            } else {
                requestPermission(Manifest.permission.SEND_SMS, REQUEST_PERMISSION_SEND_SMS);
            }
        } else {
            Toast.makeText(MainActivity.this, "Permission (already) Granted!", Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
        case REQUEST_PERMISSION_SEND_SMS: {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(MainActivity.this, "Permission Granted!", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(MainActivity.this, "Permission Denied!", Toast.LENGTH_SHORT).show();
            }
            return;
        }
        }
    }

}