Camera.java

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// -*- mode: java; c-basic-offset: 2; -*-
// Copyright 2009-2011 Google, All Rights reserved
// Copyright 2011-2020 MIT, All rights reserved
// Released under the Apache License, Version 2.0
// http://www.apache.org/licenses/LICENSE-2.0
 
package com.google.appinventor.components.runtime;
 
import android.Manifest;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Intent;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import com.google.appinventor.components.annotations.DesignerComponent;
import com.google.appinventor.components.annotations.PropertyCategory;
import com.google.appinventor.components.annotations.SimpleEvent;
import com.google.appinventor.components.annotations.SimpleFunction;
import com.google.appinventor.components.annotations.SimpleObject;
import com.google.appinventor.components.annotations.SimpleProperty;
import com.google.appinventor.components.annotations.UsesPermissions;
import com.google.appinventor.components.common.ComponentCategory;
import com.google.appinventor.components.common.YaVersion;
import com.google.appinventor.components.runtime.util.BulkPermissionRequest;
import com.google.appinventor.components.runtime.util.ErrorMessages;
import com.google.appinventor.components.runtime.util.NougatUtil;
import com.google.appinventor.components.runtime.util.QUtil;
import java.io.File;
import java.util.Date;
 
@DesignerComponent(version = YaVersion.CAMERA_COMPONENT_VERSION,
   description = "A component to take a picture using the device's camera. " +
        "After the picture is taken, the name of the file on the phone " +
        "containing the picture is available as an argument to the " +
        "AfterPicture event. The file name can be used, for example, to set " +
        "the Picture property of an Image component.",
   category = ComponentCategory.MEDIA,
   nonVisible = true,
   iconName = "images/camera.png")
@SimpleObject
@UsesPermissions(permissionNames = "android.permission.WRITE_EXTERNAL_STORAGE, android.permission.READ_EXTERNAL_STORAGE," +
                 "android.permission.CAMERA")
public class Camera extends AndroidNonvisibleComponent
    implements ActivityResultListener, Component {
 
  private static final String CAMERA_INTENT = MediaStore.ACTION_IMAGE_CAPTURE;
  private static final String CAMERA_OUTPUT = MediaStore.EXTRA_OUTPUT;
  private final ComponentContainer container;
  private Uri imageFile;
 
  /* Used to identify the call to startActivityForResult. Will be passed back
  into the resultReturned() callback method. */
  private int requestCode;
 
  // whether to open into the front-facing camera
  private boolean useFront;
 
  // wether or not we have permission to use the camera
 
  private boolean havePermission = false;
 
  public Camera(ComponentContainer container) {
    super(container.$form());
    this.container = container;
 
    // Default property values
    UseFront(false);
  }
 
  @Deprecated
  @SimpleProperty(category = PropertyCategory.BEHAVIOR)
  public boolean UseFront() {
    return useFront;
  }
 
  @Deprecated
  // Hide the deprecated property from the Designer
  //  @DesignerProperty(editorType = PropertyTypeConstants.PROPERTY_TYPE_BOOLEAN, defaultValue = "False")
  @SimpleProperty(description = "Specifies whether the front-facing camera should be used (when available). "
    + "If the device does not have a front-facing camera, this option will be ignored "
    + "and the camera will open normally.")
  public void UseFront(boolean front) {
    useFront = front;
  }
 
  @SimpleFunction
  public void TakePicture() {
    if (!havePermission) {
      final Camera me = this;
      form.askPermission(new BulkPermissionRequest(this, "TakePicture",
          Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE) {
        @Override
        public void onGranted() {
          me.havePermission = true;
          me.TakePicture();
        }
      });
      return;
    }
    String state = Environment.getExternalStorageState();
    if (Environment.MEDIA_MOUNTED.equals(state)) {
      Log.i("CameraComponent", "External storage is available and writable");
 
      File directory = new File(QUtil.getExternalStorageDir(form), "Pictures/");
      if (!directory.exists()) {
        directory.mkdir();
      }
      File image = new File(QUtil.getExternalStorageDir(form),
          "Pictures/app_inventor_" + new Date().getTime()
              + ".jpg");
      imageFile = Uri.fromFile(image);
 
      ContentValues values = new ContentValues();
      values.put(MediaStore.Images.Media.DATA, imageFile.getPath());
      values.put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg");
      values.put(MediaStore.Images.Media.TITLE, imageFile.getLastPathSegment());
 
      if (requestCode == 0) {
        requestCode = form.registerForActivityResult(this);
      }
 
      Uri imageUri;
      if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N) {
        imageUri = container.$context().getContentResolver().insert(
            MediaStore.Images.Media.INTERNAL_CONTENT_URI, values);
      } else {
        imageUri = NougatUtil.getPackageUri(form, image);
      }
      Intent intent = new Intent(CAMERA_INTENT);
      intent.putExtra(CAMERA_OUTPUT, imageUri);
 
      // NOTE: This uses an undocumented, testing feature (CAMERA_FACING).
      // It may not work in the future.
      if (useFront) {
        intent.putExtra("android.intent.extras.CAMERA_FACING", 1);
      }
 
      container.$context().startActivityForResult(intent, requestCode);
    } else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
      form.dispatchErrorOccurredEvent(this, "TakePicture",
          ErrorMessages.ERROR_MEDIA_EXTERNAL_STORAGE_READONLY);
    } else {
      form.dispatchErrorOccurredEvent(this, "TakePicture",
          ErrorMessages.ERROR_MEDIA_EXTERNAL_STORAGE_NOT_AVAILABLE);
    }
  }
 
  @Override
  public void resultReturned(int requestCode, int resultCode, Intent data) {
    Log.i("CameraComponent",
      "Returning result. Request code = " + requestCode + ", result code = " + resultCode);
    if (requestCode == this.requestCode && resultCode == Activity.RESULT_OK) {
      File image = new File(imageFile.getPath());
      if (image.length() != 0) {
        scanFileToAdd(image);
        AfterPicture(imageFile.toString());
      } else {
        deleteFile(imageFile);  // delete empty file
        // see if something useful got returned in the data
        if (data != null && data.getData() != null) {
          Uri tryImageUri = data.getData();
          Log.i("CameraComponent", "Calling Camera.AfterPicture with image path "
              + tryImageUri.toString());
          AfterPicture(tryImageUri.toString());
        } else {
          Log.i("CameraComponent", "Couldn't find an image file from the Camera result");
          form.dispatchErrorOccurredEvent(this, "TakePicture",
              ErrorMessages.ERROR_CAMERA_NO_IMAGE_RETURNED);
        }
      }
    } else {
      // delete empty file
      deleteFile(imageFile);
    }
  }
 
  private void scanFileToAdd(File image) {
    Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
    Uri contentUri = NougatUtil.getPackageUri(form, image);
    mediaScanIntent.setData(contentUri);
    container.$context().getApplicationContext().sendBroadcast(mediaScanIntent);
  }
 
  private void deleteFile(Uri fileUri) {
    File fileToDelete = new File(fileUri.getPath());
    try {
      if (fileToDelete.delete()) {
        Log.i("CameraComponent", "Deleted file " + fileUri.toString());
      } else {
        Log.i("CameraComponent", "Could not delete file " + fileUri.toString());
      }
    } catch (SecurityException e) {
      Log.i("CameraComponent", "Got security exception trying to delete file "
          + fileUri.toString());
    }
  }
 
  @SimpleEvent
  public void AfterPicture(String image) {
    EventDispatcher.dispatchEvent(this, "AfterPicture", image);
  }
}