Скачать или смотреть Resolving URI Permissions for PDF Access in SQLite Database on Android

Learn how to effectively store and access PDF `URI` in an SQLite database while overcoming permission issues in Android development.
---
This video is based on the question https://stackoverflow.com/q/62612411/ asked by the user 'Alan Scott' ( https://stackoverflow.com/u/13188249/ ) and on the answer https://stackoverflow.com/a/62612448/ provided by the user 'CommonsWare' ( https://stackoverflow.com/u/115145/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Storing uri in SQLite database, can't open PDF from uri because of permissions

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Storing and Accessing PDFs in Android: Simplifying URI Permissions

Creating an app that stores and displays PDFs can be a fun project, but it often comes with its own set of challenges. One common issue developers face is accessing a URI to open a PDF when that URI has been stored in an SQLite database. In this post, we'll discuss the specific problem of permission denial when trying to open PDFs and how to overcome it efficiently.

The Problem: Understanding the Permission Denial Error

While developing an Android app that displays PDFs, developers may encounter a frustrating error message related to permissions:

[[See Video to Reveal this Text or Code Snippet]]

This error occurs when trying to access a PDF file using its URI if proper permissions are not granted. Many first-time developers struggle with this due to a lack of knowledge around handling URI permissions in Android.

The Solution: Using ACTION_OPEN_DOCUMENT and takePersistableUriPermission()

Step 1: Intent Setup to Open Document

When you are storing the PDF files in your SQLite database, you need to ensure that you have set up your Intent properly for opening documents. Here’s how:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Granting Permissions

Using the flags FLAG_GRANT_PERSISTABLE_URI_PERMISSION and FLAG_GRANT_READ_URI_PERMISSION in your Intent might seem logical, but they do not persist permissions as you need.
Instead, you'll need to use the method takePersistableUriPermission() on a ContentResolver once you get the Uri back from your Intent. Here’s how to do it:

[[See Video to Reveal this Text or Code Snippet]]

Step 3: Storing the URI in SQLite

After successfully taking the persistent permissions, you can now store the URI in your SQLite database along with any additional details about the PDF.

Important Points to Remember

Permissions Must be Persistent: Ensure that you are calling takePersistableUriPermission() in the result callback after selecting the document to persist the permissions, enabling you to access the URI later without encountering the permission denying error.

Handle Permissions Properly: If you are not managing permissions correctly, your stored URI may later lead to a security exception when accessed.

Conclusion: Overcoming Permission Hurdles in Android Development

In summary, when working with PDFs in your Android application, storing and accessing the URI requires a careful approach to permissions. By utilizing ACTION_OPEN_DOCUMENT and takePersistableUriPermission(), you can circumvent the common pitfalls and create a smooth user experience while managing PDFs. This lesson not only helps in overcoming immediate issues but also lays a solid foundation for handling URI permissions in future Android development projects.

Remember, practice and correct implementation lead to mastery in development! Happy coding!