| /* |
| * Copyright 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.example.android.basicpermissions; |
| |
| import android.Manifest; |
| import android.app.Activity; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.pm.PackageManager; |
| import android.os.Bundle; |
| import android.support.annotation.NonNull; |
| import android.support.design.widget.Snackbar; |
| import android.support.v4.app.ActivityCompat; |
| import android.support.v7.app.AppCompatActivity; |
| import android.view.View; |
| import android.widget.Button; |
| |
| import com.example.android.basicpermissions.camera.CameraPreviewActivity; |
| |
| /** |
| * Launcher Activity that demonstrates the use of runtime permissions for Android M. |
| * This Activity requests permissions to access the camera |
| * ({@link android.Manifest.permission#CAMERA}) |
| * when the 'Show Camera Preview' button is clicked to start {@link CameraPreviewActivity} once |
| * the permission has been granted. |
| * <p> |
| * First, the status of the Camera permission is checked using {@link |
| * ActivityCompat#checkSelfPermission(Context, String)} |
| * If it has not been granted ({@link PackageManager#PERMISSION_GRANTED}), it is requested by |
| * calling |
| * {@link ActivityCompat#requestPermissions(Activity, String[], int)}. The result of the request is |
| * returned to the |
| * {@link android.support.v4.app.ActivityCompat.OnRequestPermissionsResultCallback}, which starts |
| * {@link |
| * CameraPreviewActivity} if the permission has been granted. |
| * <p> |
| * Note that there is no need to check the API level, the support library |
| * already takes care of this. Similar helper methods for permissions are also available in |
| * ({@link ActivityCompat}, |
| * {@link android.support.v4.content.ContextCompat} and {@link android.support.v4.app.Fragment}). |
| */ |
| public class MainActivity extends AppCompatActivity |
| implements ActivityCompat.OnRequestPermissionsResultCallback { |
| |
| private static final int PERMISSION_REQUEST_CAMERA = 0; |
| |
| private View mLayout; |
| |
| @Override |
| protected void onCreate(Bundle savedInstanceState) { |
| super.onCreate(savedInstanceState); |
| setContentView(R.layout.activity_main); |
| mLayout = findViewById(R.id.main_layout); |
| |
| // Register a listener for the 'Show Camera Preview' button. |
| findViewById(R.id.button_open_camera).setOnClickListener(new View.OnClickListener() { |
| @Override |
| public void onClick(View view) { |
| showCameraPreview(); |
| } |
| }); |
| } |
| |
| @Override |
| public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, |
| @NonNull int[] grantResults) { |
| // BEGIN_INCLUDE(onRequestPermissionsResult) |
| if (requestCode == PERMISSION_REQUEST_CAMERA) { |
| // Request for camera permission. |
| if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { |
| // Permission has been granted. Start camera preview Activity. |
| Snackbar.make(mLayout, R.string.camera_permission_granted, |
| Snackbar.LENGTH_SHORT) |
| .show(); |
| startCamera(); |
| } else { |
| // Permission request was denied. |
| Snackbar.make(mLayout, R.string.camera_permission_denied, |
| Snackbar.LENGTH_SHORT) |
| .show(); |
| } |
| } |
| // END_INCLUDE(onRequestPermissionsResult) |
| } |
| |
| private void showCameraPreview() { |
| // BEGIN_INCLUDE(startCamera) |
| // Check if the Camera permission has been granted |
| if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) |
| == PackageManager.PERMISSION_GRANTED) { |
| // Permission is already available, start camera preview |
| Snackbar.make(mLayout, |
| R.string.camera_permission_available, |
| Snackbar.LENGTH_SHORT).show(); |
| startCamera(); |
| } else { |
| // Permission is missing and must be requested. |
| requestCameraPermission(); |
| } |
| // END_INCLUDE(startCamera) |
| } |
| |
| /** |
| * Requests the {@link android.Manifest.permission#CAMERA} permission. |
| * If an additional rationale should be displayed, the user has to launch the request from |
| * a SnackBar that includes additional information. |
| */ |
| private void requestCameraPermission() { |
| // Permission has not been granted and must be requested. |
| if (ActivityCompat.shouldShowRequestPermissionRationale(this, |
| Manifest.permission.CAMERA)) { |
| // Provide an additional rationale to the user if the permission was not granted |
| // and the user would benefit from additional context for the use of the permission. |
| // Display a SnackBar with cda button to request the missing permission. |
| Snackbar.make(mLayout, R.string.camera_access_required, |
| Snackbar.LENGTH_INDEFINITE).setAction(R.string.ok, new View.OnClickListener() { |
| @Override |
| public void onClick(View view) { |
| // Request the permission |
| ActivityCompat.requestPermissions(MainActivity.this, |
| new String[]{Manifest.permission.CAMERA}, |
| PERMISSION_REQUEST_CAMERA); |
| } |
| }).show(); |
| |
| } else { |
| Snackbar.make(mLayout, R.string.camera_unavailable, Snackbar.LENGTH_SHORT).show(); |
| // Request the permission. The result will be received in onRequestPermissionResult(). |
| ActivityCompat.requestPermissions(this, |
| new String[]{Manifest.permission.CAMERA}, PERMISSION_REQUEST_CAMERA); |
| } |
| } |
| |
| private void startCamera() { |
| Intent intent = new Intent(this, CameraPreviewActivity.class); |
| startActivity(intent); |
| } |
| |
| } |