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Camera Intent not saving photo

开发者 https://www.devze.com 2023-04-11 21:53 出处:网络
I successfully have used this code snippet before, but with the file pointing to somewhere on the SD card.

I successfully have used this code snippet before, but with the file pointing to somewhere on the SD card.

final File temp = new File(getCacheDir(), "temp.jpg");
temp.delete();
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(temp));
startActivityForResult(intent, CONFIG.Intents.Action开发者_高级运维s.SELECT_CAMERA_PHOTO);

However when I use getCacheDir instead of a loc on the SD card it seems the photo is never saved. Is this a limitation of cache dir and image capture?


Technically, this is because writing to internal storage is not supported when using the Camera application to capture an image. In fact, you may notice an exception printed in logcat stating Writing to internal storage is not supported. However, the real reason this doesn't work is because by default you are creating a file that is private to your application package and another application (i.e. the Camera app) can't access that file location because it doesn't have permission to do so. External storage is the only globally accessibly portion of the filesystem.

The workaround is for you to create the file with global (WORLD_WRITEABLE) permissions. Typically, this allows the Camera app to access the file via the passed Uri. There aren't really methods to do this directly on File, so you have to create the file using the methods available in Context and then grab a handle to it afterward:

//Remove if exists, the file MUST be created using the lines below
File f = new File(getFilesDir(), "Captured.jpg");
f.delete();
//Create new file
FileOutputStream fos = openFileOutput("Captured.jpg", Context.MODE_WORLD_WRITEABLE);
fos.close();
//Get reference to the file
File f = new File(getFilesDir(), "Captured.jpg");

This also sort of limits where you can place the file since the Context methods inherently create files in the root "files" directory, and you can't redirect that to the cache directory.

HTH


Best solution I found is: FileProvider (needs support-library-v4)
It uses the internal storage! https://developer.android.com/reference/android/support/v4/content/FileProvider.html

  1. Define your FileProvider in Manifest in Application element:

    <provider
          android:name="android.support.v4.content.FileProvider"
          android:authorities="your.package.name.fileprovider"
          android:exported="false"
          android:grantUriPermissions="true" >
          <meta-data
                     android:name="android.support.FILE_PROVIDER_PATHS"
                     android:resource="@xml/image_path" />
    </provider>
    
  2. Add camera feature to AndroidManifest.xml's root element if mandatory:

    <uses-feature android:name="android.hardware.camera"
    android:required="true" />
    
  3. Define your image paths in for example res/xml/image_path.xml:

    <paths xmlns:android="http://schemas.android.com/apk/res/android">
    <files-path name="captured_image" path="your/path/"/>
    </paths>
    
  4. Java:

    private static final int IMAGE_REQUEST_CODE = 1;
    // your authority, must be the same as in your manifest file 
    private static final String CAPTURE_IMAGE_FILE_PROVIDER = "your.package.name.fileprovider";
    

4.1 capture intent:

    File path = new File(activity.getFilesDir(), "your/path");
    if (!path.exists()) path.mkdirs();
    File image = new File(path, "image.jpg");
    Uri imageUri = FileProvider.getUriForFile(activity, CAPTURE_IMAGE_FILE_PROVIDER, image);
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
    startActivityForResult(intent, IMAGE_REQUEST_CODE);

4.2 onActivityResult():

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent intent) {
        if (requestCode == IMAGE_REQUEST_CODE) {
            if (resultCode == Activity.RESULT_OK) {
                File path = new File(getFilesDir(), "your/path");
                if (!path.exists()) path.mkdirs();
                File imageFile = new File(path, "image.jpg");
                // use imageFile to open your image
            }
        }
        super.onActivityResult(requestCode, resultCode, intent);
    }
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