来自App的Android Image Viewer

Question

我正在尝试使用内置的Android图像查看器启动写入我的应用程序目录的图像.此图像已在app的不同部分写入app目录.获取以下文件时:

super.getFilesDir() + "/current.png"

File.exists()返回true.

如何启动内置​​的Android图像查看器来查看此文件？目前我在做:

File f = new File(super.getFilesDir()+"/current.png");
uri = Uri.parse("file://"+super.getFilesDir()+"/current.png");
startActivity(new Intent(Intent.ACTION_VIEW, uri));

它一直在搅拌:

10-11 13:09:24.367:INFO/ActivityManager(564):开始活动:Intent {act = android.intent.action.VIEW dat = file:///data/data/com.davidgoemans.myapp/files/current .png} 10-11 13:09:24.367:ERROR/myapp(2166):异常occuredandroid.content.ActivityNotFoundException:找不到处理Intent的Activity {act = android.intent.action.VIEW dat = file:/// data /data/com.davidgoemans.myapp/files/current.png}

无论我将uri架构更改为什么(例如,content://,file://,media://,image://).

Answer 1

一种方法是实现上下文提供程序,以便其他应用程序访问您的数据.

创建一个新类,其中包含:

public class FileContentProvider extends ContentProvider {
   private static final String URI_PREFIX = "content://uk.co.ashtonbrsc.examplefilecontentprovider";

   public static String constructUri(String url) {
       Uri uri = Uri.parse(url);
       return uri.isAbsolute() ? url : URI_PREFIX + url;
   }

   @Override
   public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
       File file = new File(uri.getPath());
       ParcelFileDescriptor parcel = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
       return parcel;
   }

   @Override
   public boolean onCreate() {
       return true;
   }

   @Override
   public int delete(Uri uri, String s, String[] as) {
       throw new UnsupportedOperationException("Not supported by this provider");
   }

   @Override
   public String getType(Uri uri) {
   throw new UnsupportedOperationException("Not supported by this provider");
   }

   @Override
   public Uri insert(Uri uri, ContentValues contentvalues) {
       throw new UnsupportedOperationException("Not supported by this provider");
   }

   @Override
   public Cursor query(Uri uri, String[] as, String s, String[] as1, String s1) {
       throw new UnsupportedOperationException("Not supported by this provider");
   }

   @Override
   public int update(Uri uri, ContentValues contentvalues, String s, String[] as) {
       throw new UnsupportedOperationException("Not supported by this provider");
   }

}

将内容提供程序添加到AndroidManifest.xml:

<provider android:name=".FileContentProvider" android:authorities="uk.co.ashtonbrsc.examplefilecontentprovider" />

然后,您应该可以"content://uk.co.ashtonbrsc.examplefilecontentprovider/" + the full path to the image在ACTION_VIEW意图中使用.