android - 从图库中选取图像并设置为 imageview

Question

我正在尝试从图库中选择图像并将其设置为 imageview。

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    try {
        // When an Image is picked
        if (requestCode == RESULT_LOAD_IMG && resultCode == RESULT_OK
                && null != data) {

            Log.e("1","1");
            // Get the Image from data

            Uri selectedImage = data.getData();
            Log.e("2","2");

            String[] filePathColumn = { MediaStore.Images.Media.DATA };
            Log.e("3","3");

            // Get the cursor
            Cursor cursor = getContentResolver().query(selectedImage,
                    filePathColumn, null, null, null);
            Log.e("4","4");
            // Move to first row
            cursor.moveToFirst();
            Log.e("5", "5");

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            Log.e("6","6");
            imgDecodableString = cursor.getString(columnIndex);
            Log.e("7","7");
            cursor.close();
            ImageView imgView = (ImageView) findViewById(R.id.imgView);
            Log.e("8","8");
            // Set the Image in ImageView after decoding the String
            imgView.setImageBitmap(BitmapFactory
                    .decodeFile(imgDecodableString));

        } else {
            Toast.makeText(this, "You haven't picked Image",
                    Toast.LENGTH_LONG).show();
        }
    } catch (Exception e) {
        Toast.makeText(this, "Something went wrong", Toast.LENGTH_LONG)
                .show();
    }

}

在日志中它只显示第三个日志，然后显示捕获的 toast。我用的是三星S4，安卓版本是5.0.1。我认为，问题出在光标上，但无法修复。请帮助我。

Answer 1

这是我用于选择图库图像然后将其显示到 ImageView 的代码。您可以根据需要使用。

这里是打开 Gallery Intent 的方法。

private static final int GALLERY_PHOTO = 111;

private void pickGalleryImage() {
     Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
     intent.setType("image/*");
     startActivityForResult(chooserIntent, GALLERY_PHOTO);
}

那么你的onActivityResult() 方法应该是这样的。在此方法中，mContext 指的是 Activity 的上下文。如果 Activity 名称是 MainActivity 那么您可以使用 MainActivity.this

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
      super.onActivityResult(requestCode, resultCode, data);
      if (requestCode == GALLERY_PHOTO && resultCode == Activity.RESULT_OK) {
          if (data.getData() != null) {
                String filePath = GetFilePathFromDevice.getPath(mContext, data.getData());
                Bitmap bm = BitmapFactory.decodeFile(filePath);
                imgView.setImageBitmap(bm);
           }      
      } 
}

这里是 GetFilePathFromDevice 类，在 onActivityResult() 方法中用于从 Gallery 中获取所选图像的文件路径。

public final class GetFilePathFromDevice {

    /**
     * Get file path from URI
     *
     * @param context context of Activity
     * @param uri     uri of file
     * @return path of given URI
     */
    public static String getPath(final Context context, final Uri uri) {
        final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
        // DocumentProvider
        if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            // ExternalStorageProvider
            if (isExternalStorageDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/" + split[1];
                }
            }
            // DownloadsProvider
            else if (isDownloadsDocument(uri)) {
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
                return getDataColumn(context, contentUri, null, null);
            }
            // MediaProvider
            else if (isMediaDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }
                final String selection = "_id=?";
                final String[] selectionArgs = new String[]{split[1]};
                return getDataColumn(context, contentUri, selection, selectionArgs);
            }
        }
        // MediaStore (and general)
        else if ("content".equalsIgnoreCase(uri.getScheme())) {
            // Return the remote address
            if (isGooglePhotosUri(uri))
                return uri.getLastPathSegment();
            return getDataColumn(context, uri, null, null);
        }
        // File
        else if ("file".equalsIgnoreCase(uri.getScheme())) {
            return uri.getPath();
        }
        return null;
    }

    public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
        Cursor cursor = null;
        final String column = "_data";
        final String[] projection = {column};
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
            if (cursor != null && cursor.moveToFirst()) {
                final int index = cursor.getColumnIndexOrThrow(column);
                return cursor.getString(index);
            }
        } finally {
            if (cursor != null)
                cursor.close();
        }
        return null;
    }

    public static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

    public static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }

    public static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

    public static boolean isGooglePhotosUri(Uri uri) {
        return "com.google.android.apps.photos.content".equals(uri.getAuthority());
    }
}

希望对你有帮助。