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。
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。
试试这个:
if (Build.VERSION.SDK_INT <19){
Intent intent = new Intent();
intent.setType("image/jpeg");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, getResources().getString(R.string.select_picture)),GALLERY_INTENT_CALLED);
} else {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/jpeg");
startActivityForResult(intent, GALLERY_KITKAT_INTENT_CALLED);
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode != Activity.RESULT_OK) return;
if (null == data) return;
Uri originalUri = null;
if (requestCode == GALLERY_INTENT_CALLED) {
originalUri = data.getData();
} else if (requestCode == GALLERY_KITKAT_INTENT_CALLED) {
originalUri = data.getData();
final int takeFlags = data.getFlags()
& (Intent.FLAG_GRANT_READ_URI_PERMISSION
| Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
// Check for the freshest data.
getContentResolver().takePersistableUriPermission(originalUri, takeFlags);
}
loadSomeStreamAsynkTask(originalUri);
}
可能需要
@SuppressLint（“NewApi”）
for
takePersistableUriPermission
我已经将多个答案组合成一个工作解决方案，结果与文件路径
Mime类型与示例目的无关。
Intent intent;
if(Build.VERSION.SDK_INT >= 19){
intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, false);
intent.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION);
}else{
intent = new Intent(Intent.ACTION_GET_CONTENT);
}
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intent.setType("application/octet-stream");
if(isAdded()){
startActivityForResult(intent, RESULT_CODE);
}
处理结果
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if( requestCode == RESULT_CODE && resultCode == Activity.RESULT_OK) {
Uri uri = data.getData();
if (uri != null && !uri.toString().isEmpty()) {
if(Build.VERSION.SDK_INT >= 19){
final int takeFlags = data.getFlags() & Intent.FLAG_GRANT_READ_URI_PERMISSION;
//noinspection ResourceType
getActivity().getContentResolver()
.takePersistableUriPermission(uri, takeFlags);
}
String filePath = FilePickUtils.getSmartFilePath(getActivity(), uri);
// do what you need with it...
}
}
}
FilePickUtils
import android.annotation.SuppressLint;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
public class FilePickUtils {
private static String getPathDeprecated(Context ctx, Uri uri) {
if( uri == null ) {
return null;
}
String[] projection = { MediaStore.Images.Media.DATA };
Cursor cursor = ctx.getContentResolver().query(uri, projection, null, null, null);
if( cursor != null ){
int column_index = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
return uri.getPath();
}
public static String getSmartFilePath(Context ctx, Uri uri){
if (Build.VERSION.SDK_INT < 19) {
return getPathDeprecated(ctx, uri);
}
return FilePickUtils.getPath(ctx, uri);
}
@SuppressLint("NewApi")
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];
}
// TODO handle non-primary volumes
}
// 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 getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}
return null;
}
/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
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;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
}
推荐文章
- 警告:API ' variable . getjavacompile()'已过时，已被' variable . getjavacompileprovider()'取代
- 安装APK时出现错误
- 碎片中的onCreateOptionsMenu
- TextView粗体通过XML文件?
- 如何使线性布局的孩子之间的空间?
- DSL元素android.dataBinding。enabled'已过时，已被'android.buildFeatures.dataBinding'取代
- ConstraintLayout:以编程方式更改约束
- PANIC: AVD系统路径损坏。检查ANDROID_SDK_ROOT值
- 如何生成字符串类型的buildConfigField
- Recyclerview不调用onCreateViewHolder
- Android API 21工具栏填充
- Android L中不支持操作栏导航模式
- 如何在TextView中添加一个子弹符号?
- PreferenceManager getDefaultSharedPreferences在Android Q中已弃用
- 在Android Studio中创建aar文件
