与Android应用程序中的内容提供商共享图像 [英] Share an image with a content provider in Android app
问题描述
我正在开发一个Android应用程序，该应用程序是一个图像库，其中图像是从互联网下载的，并显示在smathphone的屏幕上.图像一次显示一次，应用程序有一个按钮可以共享显示的图像.
I'm developing an Android app that is a gallery of images in which the images are downloaded from internet for display on the screen of smathphone. Images are displayed one at a time and the application has a button to share the image that is displayed.
按照我在某些StackOverflow帖子中找到的指示(指示共享图像的正确方法是使用ContentProvider)的指示，我实现了以下代码，可用于共享某些应用程序(例如Twitter，Gmail等)的图像. )，但不适用于其他人(Facebook，Yahoo，MMS ...).
Following the directions I've found in some StackOverflow post which indicated that the right way to share an image was using a ContentProvider I have implemented the following code that works to share the images of certain applications (eg Twitter, Gmail ...) but does not work for others (Facebook, Yahoo, MMS ...).
然后，我展示了所使用的代码，希望您可以帮助我获得正确的实现，以在所有应用程序中共享图像.
Then I show the code used hoping you can help me get the correct implementation to share images in all applications.
最初，我捕获了要共享的按钮:
Initially I capture the button press to share:
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.menu_share) {
// I get the image being displayed on the screen
View root = getView();
ImageView imageView = (ImageView) root.findViewById(R.id.image);
Drawable imageToShareDrawable = imageView.getDrawable();
if (imageToShareDrawable instanceof BitmapDrawable) {
// I convert the image to Bitmap
Bitmap imageToShare = ((BitmapDrawable) imageToShareDrawable).getBitmap();
// Name of de image extracted from a bean property
String fileName = quote.getImage();
// I keep the image in the folder "files" of internal storage application
TempInternalStorage.createCachedFile(fileName, imageToShare, getActivity().getApplicationContext());
// I start the Activity to select the application to share the image after the intent Built with the method "getDefaultShareIntent"
startActivity(getDefaultShareIntent(fileName));
} else {
Toast.makeText(getActivity().getApplicationContext(), "Please wait, the quote is being downloaded", Toast.LENGTH_SHORT).show();
}
}
return true;
}
将图像保存到应用程序内部存储器的方法如下:
The method for saving the image to the internal storage of the application is as follows:
public static void createCachedFile(String fileName, Bitmap image, Context context) {
try {
File file = new File(context.getFilesDir(), fileName);
if (!file.exists()) {
FileOutputStream fos = new FileOutputStream(file);
image.compress(Bitmap.CompressFormat.JPEG, 100, fos);
fos.flush();
fos.close();
}
} catch (Exception e) {
Log.e("saveTempFile()", "**** Error");
}
}
构造意图以共享它的方法:
The method that constructs the Intent to share it:
private Intent getDefaultShareIntent(String fileName) {
final Intent shareIntent = new Intent();
shareIntent.setAction(Intent.ACTION_SEND);
shareIntent.setType("image/jpeg");
shareIntent.putExtra(Intent.EXTRA_TEXT, "Test text");
shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse("content://" + CachedFileProvider.AUTHORITY + File.separator + "img" + File.separator + fileName));
shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
return shareIntent;
}
最后，ContentProvider代码如下:
Finally ContentProvider code is as follows:
public class CachedFileProvider extends ContentProvider {
private static final String CLASS_NAME = "CachedFileProvider";
public static final String AUTHORITY = "com.example.appname.cachefileprovider";
private UriMatcher uriMatcher;
@Override
public boolean onCreate() {
uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
uriMatcher.addURI(AUTHORITY, "img/*", 1);
return true;
}
@Override
public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
String LOG_TAG = CLASS_NAME + " - openFile";
Log.i(LOG_TAG, "Called with uri: '" + uri + "'." + uri.getLastPathSegment());
switch (uriMatcher.match(uri)) {
case 1:
String fileLocation = getContext().getFilesDir() + File.separator + uri.getLastPathSegment();
ParcelFileDescriptor image = ParcelFileDescriptor.open(new File(fileLocation), ParcelFileDescriptor.MODE_READ_ONLY);
return image;
default:
Log.i(LOG_TAG, "Unsupported uri: '" + uri + "'.");
throw new FileNotFoundException("Unsupported uri: " + uri.toString());
}
}
@Override
public int update(Uri uri, ContentValues contentvalues, String s, String[] as) {
return 0;
}
@Override
public int delete(Uri uri, String s, String[] as) {
return 0;
}
@Override
public Uri insert(Uri uri, ContentValues contentvalues) {
return null;
}
@Override
public String getType(Uri uri) {
return null;
}
@Override
public Cursor query(Uri uri, String[] projection, String s, String[] as1, String s1) {
MatrixCursor c = null;
Log.i(">>>> projection", java.util.Arrays.toString(projection));
String fileLocation = getContext().getFilesDir() + File.separator + uri.getLastPathSegment();
File file = new File(fileLocation);
long time = System.currentTimeMillis();
c = new MatrixCursor(new String[] { "_id", "_data", "orientation", "mime_type", "datetaken", "_display_name" });
c.addRow(new Object[] { 0, file, 0, "image/jpeg", time, uri.getLastPathSegment() });
return c;
}
@Override
public String[] getStreamTypes(Uri uri, String mimeTypeFilter) {
return null;
}
}
我发现，当共享图像时，某些应用程序仅调用方法"query"(在这些地方代码不起作用，我无法共享图像)，而有些其他应用程序也将方法称为"query"也将方法称为"openFile"，它们可以正常工作，并且我可以共享图像.
I have found that when the image is sharing some applications only call the method "query" (these are where the code does not work and I can not share the image) while there are others that also call the method "query" also call the method "openFile" and these do work and I can share the image.
希望您能帮助我，非常感谢.
I hope you can help me, thank you very much in advance.
推荐答案
正如@Sun Ning-s的注释所指出的那样，某些共享目标应用程序"可以处理以"content://.."开头的URI-s.
As @Sun Ning-s comment noted some "share target apps" can handle URI-s starting with "content://.." which you have implemented.
其他应用处理以"file://...."开头的文件uri-s，因此您必须实现第二个共享菜单共享为文件"
Other apps handle file uri-s starting with "file://...." so you have to implement a 2nd share menue "share as file"
private Intent getFileShareIntent(String fullPathTofile) {
final Intent shareIntent = new Intent();
shareIntent.setAction(Intent.ACTION_SEND);
shareIntent.setType("image/jpeg");
shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse("file://" + fullPathTofile));
shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
return shareIntent;
}
您可以使用 Android应用程序intentintercept 来查找其他共享源应用"所提供的内容.
You can use the android app intentintercept to find out what other "share source apps" provide.
这篇关于与Android应用程序中的内容提供商共享图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
