Question

我有两个活动：MainActivity和ShowPhotoDescriptionActivity。第一个活动有一个FloatingActionButton，当按下它时，它会启动相机，拍摄照片，将其保存到此应用程序的文件夹中。之后，调用第二个Activity。此活动应显示在ImageView中拍摄的最后一张照片。它看起来很简单但没有任何作用我已经尝试了一些解决方案，但大多数都没有解决我的任何问题。

在MainActivity中我有

FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            //Starts the device's camera
            dispatchTakePicture();

        }
    });

/**
 * Calls an existent camera app to take a picture, then is stores on device in a custom folder
 */
private void dispatchTakePicture() {

    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // Ensure that there's a camera activity to handle the intent
    if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
        // Create the File where the photo should go
        File photoFile = null;
        try {
            String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
            String imageFileName = "photocrowd" + timeStamp + ".jpg";
            final String appDirectoryName = "Photocrowd";
            photoFile = createImageFile(appDirectoryName, imageFileName);
        } catch (IOException ex) {
            // Error occurred while creating the File
            Toast.makeText(this, "Ocorreu um erro: Não foi posível armazenar a foto", Toast.LENGTH_SHORT).show();
            Log.e("Main Activity", "It wasn't possible to catch the photo: "+ex);
        }
        // Continue only if the File was successfully created
        if (photoFile != null) {

            Uri photoURI = Uri.fromFile(photoFile);
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
            startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
        }
    }
}

/**
 * Creates a folder and a name to the image on the device
 *
 * @return
 * @throws IOException
 */
private File createImageFile(String name_folder, String name_image) throws IOException {
    // Create an image file name
    final File imageRoot = new File(Environment.getExternalStoragePublicDirectory(
            Environment.DIRECTORY_PICTURES), name_folder);
    imageRoot.mkdir();
    File image = new File(imageRoot, name_image);

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = image.getAbsolutePath();

    return image;
}
/**
 * Allows the photo be found for the media scanner and shown in gallery
 */
private void galleryAddPic() {
    Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
    File f = new File(mCurrentPhotoPath);
    Uri contentUri = Uri.fromFile(f);
    mediaScanIntent.setData(contentUri);
    this.sendBroadcast(mediaScanIntent);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {

    if (requestCode == REQUEST_TAKE_PHOTO && resultCode == RESULT_OK) {

        galleryAddPic();
        //Once the photo is taken and saved, the description activity is called
        Intent i = new Intent(this, PhotoDescriptionActivity.class);

        i.putExtra("path", mCurrentPhotoPath);

        startActivity(i);
    }
}

好吧，这只是拍摄照片，保存在名为＆＃34; Photocrowd＆＃34;的文件夹中，将其显示在图库中并将路径发送到其他活动。

在PhotoDescriptionActivity中我有

private ImageView mImageView;
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.show_photo_description_activity);
    Log.v("DESCRIPTION", "Activite PHotoDescription");
    mImageView = (ImageView) findViewById(R.id.photo_panel);

    String imageRoot = getIntent().getStringExtra("path");
    Log.v("DESCRIPTION", imageRoot);

    mImageView.setImageBitmap(BitmapFactory.decodeFile(imageRoot));

}

我已经尝试过使用其他方法（使用库，setImageUri等）。 imageRoot的路径与Android（/storage/emulated/0/Pictures/Photocrowd/photocrowd20170419_124851.jpg）

中的照片说明相同

此代码是我尝试的最后一个代码，它显示在Log：

中

E/BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /storage/emulated/0/Pictures/Photocrowd/photocrowd20170419_130554.jpg: open failed: EACCES (Permission denied)

我在Manifest中写了这些权限：

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

我怎样才能将最后一张照片拍摄下来并保存在我的画廊中？我知道它看起来很简单但没有任何效果。

Answer 1

您未获得许可＆＃34; WRITE_EXTERNAL_STORAGE＆＃34;如您的日志中所述： E/BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /storage/emulated/0/Pictures/Photocrowd/photocrowd20170419_130554.jpg: open failed: EACCES (Permission denied)。

此权限：<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />是危险权限，从Android 6.0开始，您需要在运行时请求权限：

从Android 6.0（API级别23）开始，用户在应用程序运行时向应用程序授予权限，而不是在安装应用程序时。此方法简化了应用安装过程，因为用户在安装或更新应用时无需授予权限。它还使用户可以更好地控制应用程序的功能;

您可以在Google Guide

了解更多信息

为了便于编码，我建议您使用：PermissionsDispatcher，但它易于使用，并使您的代码更清晰。

拍摄照片并在另一个活动的ImageView中显示

1 个答案: