在奇巧(或新画廊)之前,意图。ACTION_GET_CONTENT返回一个这样的URI
内容:/ /媒体/外部/图片/媒体/ 3951。
使用ContentResolver并查询 media . data返回文件URL。
然而,在奇巧,画廊返回一个URI(通过“Last”)像这样:
内容:/ / com.android.providers.media.documents /文档/图片:3951
我该怎么处理呢?
在奇巧(或新画廊)之前,意图。ACTION_GET_CONTENT返回一个这样的URI
内容:/ /媒体/外部/图片/媒体/ 3951。
使用ContentResolver并查询 media . data返回文件URL。
然而,在奇巧,画廊返回一个URI(通过“Last”)像这样:
内容:/ / com.android.providers.media.documents /文档/图片:3951
我该怎么处理呢?
当前回答
正如commonware提到的,你不应该假设,你通过ContentResolver得到的流可以转换成文件。
你真正应该做的是从ContentProvider打开InputStream,然后从中创建一个位图。而且它在4.4和更早的版本上也可以工作,不需要反射。
//cxt -> current context
InputStream input;
Bitmap bmp;
try {
input = cxt.getContentResolver().openInputStream(fileUri);
bmp = BitmapFactory.decodeStream(input);
} catch (FileNotFoundException e1) {
}
当然,如果你处理大图片,你应该用适当的inSampleSize: http://developer.android.com/training/displaying-bitmaps/load-bitmap.html加载它们。但那是另一个话题了。
其他回答
你的问题的答案是你需要有权限。在manifest.xml文件中输入以下代码:
<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="18" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.WRITE_OWNER_DATA"></uses-permission>
<uses-permission android:name="android.permission.READ_OWNER_DATA"></uses-permission>`
这对我很管用……
我相信已经发布的回复应该会让人们朝着正确的方向前进。然而,以下是我所做的对我正在更新的遗留代码有意义的事情。遗留代码使用图库中的URI来更改和保存图像。
在4.4之前(和谷歌驱动器),uri看起来是这样的: 内容:/ /媒体/外部/图片/媒体/ 41
正如问题中所述,它们通常是这样的: 内容:/ / com.android.providers.media.documents /文档/图片:3951
因为我需要保存图像的能力,而不打扰已经存在的代码,我只是从图库中复制URI到应用程序的数据文件夹中。然后从数据文件夹中保存的图像文件中产生一个新的URI。
这个想法是这样的:
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent), CHOOSE_IMAGE_REQUEST);
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
File tempFile = new File(this.getFilesDir().getAbsolutePath(), "temp_image");
//Copy URI contents into temporary file.
try {
tempFile.createNewFile();
copyAndClose(this.getContentResolver().openInputStream(data.getData()),new FileOutputStream(tempFile));
}
catch (IOException e) {
//Log Error
}
//Now fetch the new URI
Uri newUri = Uri.fromFile(tempFile);
/* Use new URI object just like you used to */
}
注意- copyAndClose()只是执行文件I/O,将InputStream复制到FileOutputStream。代码没有被发布。
对于这种类型的uri 内容:/ / % 3 a19298 com.android.providers.media.documents /文件/文档 或者uri.getAuthority()是这些中的任何一个
"com.google.android.apps.docs.storage".equals(uri.getAuthority()) || "com.google.android.apps.docs.storage.legacy".equals(uri.getAuthority());
使用这个函数
private static String getDriveFilePath(Uri uri, Context context) {
Uri returnUri = uri;
Cursor returnCursor = context.getContentResolver().query(returnUri, null, null, null, null);
int nameIndex = returnCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
int sizeIndex = returnCursor.getColumnIndex(OpenableColumns.SIZE);
returnCursor.moveToFirst();
String name = (returnCursor.getString(nameIndex));
String size = (Long.toString(returnCursor.getLong(sizeIndex)));
File file = new File(context.getCacheDir(), name);
try {
InputStream inputStream = context.getContentResolver().openInputStream(uri);
FileOutputStream outputStream = new FileOutputStream(file);
int read = 0;
int maxBufferSize = 1 * 1024 * 1024;
int bytesAvailable = inputStream.available();
//int bufferSize = 1024;
int bufferSize = Math.min(bytesAvailable, maxBufferSize);
final byte[] buffers = new byte[bufferSize];
while ((read = inputStream.read(buffers)) != -1) {
outputStream.write(buffers, 0, read);
}
Log.e("File Size", "Size " + file.length());
inputStream.close();
outputStream.close();
Log.e("File Path", "Path " + file.getPath());
Log.e("File Size", "Size " + file.length());
} catch (Exception e) {
Log.e("Exception", e.getMessage());
}
return file.getPath();
}
@paul burke的答案适用于API级别19及以上的相机和画廊图片,但如果你的Android项目的最低SDK设置为19以下,它就不起作用,上面提到的一些答案并不适用于画廊和相机。好吧,我已经修改了@paul burke的代码,它适用于API级别低于19的代码。下面是代码。
public static String getPath(final Context context, final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >=
Build.VERSION_CODES.KITKAT;
Log.i("URI",uri+"");
String result = uri+"";
// DocumentProvider
// if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
if (isKitKat && (result.contains("media.documents"))) {
String[] ary = result.split("/");
int length = ary.length;
String imgary = ary[length-1];
final String[] dat = imgary.split("%3A");
final String docId = dat[1];
final String type = dat[0];
Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
}
else if ("video".equals(type)) {
}
else if ("audio".equals(type)) {
}
final String selection = "_id=?";
final String[] selectionArgs = new String[] {
dat[1]
};
return getDataColumn(context, contentUri, selection, selectionArgs);
}
else
if ("content".equalsIgnoreCase(uri.getScheme())) {
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 column_index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(column_index);
}
}
finally {
if (cursor != null)
cursor.close();
}
return null;
}
我在这里尝试了几个答案,我认为我有一个解决方案,每次都可以工作,并且还可以管理权限。
这是基于LEO的巧妙解决方案。这篇文章应该包含所有的代码,你需要使这个工作,它应该工作在任何手机和Android版本;)
为了能够从SD卡中选择文件,你需要在你的清单中这样做:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
常量:
private static final int PICK_IMAGE = 456; // Whatever number you like
public static final int MY_PERMISSIONS_REQUEST_READ_EXTERNAL = 28528; // Whatever number you like
public static final String FILE_TEMP_NAME = "temp_image"; // Whatever file name you like
检查权限和launchImagePick如果可能的话
if (ContextCompat.checkSelfPermission(getThis(),
Manifest.permission.READ_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(getThis(),
new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
MY_PERMISSIONS_REQUEST_READ_EXTERNAL);
}
else {
launchImagePick();
}
允许响应
@Override
public void onRequestPermissionsResult(int requestCode,
@NonNull
String permissions[],
@NonNull
int[] grantResults) {
if (manageReadExternalPermissionResponse(this, requestCode, grantResults)) {
launchImagePick();
}
}
管理权限响应
public static boolean manageReadExternalPermissionResponse(final Activity activity, int requestCode, int[] grantResults) {
if (requestCode == MY_PERMISSIONS_REQUEST_READ_EXTERNAL) {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Permission was granted, yay! Do the
// contacts-related task you need to do.
return true;
} else if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_DENIED) {
boolean showRationale = ActivityCompat.shouldShowRequestPermissionRationale(activity,
Manifest.permission.READ_EXTERNAL_STORAGE);
if (!showRationale) {
// The user also CHECKED "never ask again".
// You can either enable some fall back,
// disable features of your app
// or open another dialog explaining
// again the permission and directing to
// the app setting.
} else {
// The user did NOT check "never ask again".
// This is a good place to explain the user
// why you need the permission and ask if he/she wants
// to accept it (the rationale).
}
} else {
// Permission denied, boo! Disable the
// functionality that depends on this permission.
}
}
return false;
}
发射图像选择
private void launchImagePick() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
startActivityForResult(intent, PICK_IMAGE);
// see onActivityResult
}
管理图像选择响应
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PICK_IMAGE) {
if (resultCode == Activity.RESULT_OK) {
if (data != null && data.getData() != null) {
try {
InputStream inputStream = getContentResolver().openInputStream(data.getData())
if (inputStream != null) {
// No special persmission needed to store the file like that
FileOutputStream fos = openFileOutput(FILE_TEMP_NAME, Context.MODE_PRIVATE);
final int BUFFER_SIZE = 1 << 10 << 3; // 8 KiB buffer
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = -1;
while ((bytesRead = inputStream.read(buffer)) > -1) {
fos.write(buffer, 0, bytesRead);
}
inputStream.close();
fos.close();
File tempImageFile = new File(getFilesDir()+"/"+FILE_TEMP_NAME);
// Do whatever you want with the File
// Delete when not needed anymore
deleteFile(FILE_TEMP_NAME);
}
}
catch (Exception e) {
e.printStackTrace();
}
} else {
// Error display
}
} else {
// The user did not select any image
}
}
}
这就是所有的人;这在我所有的电话上都适用。