[#1101]Add Scan QR code from saved picture feature

[Xi-Zhang1]

Description

Add Scan QR code from saved picture feature, enabling users to import QR code images from the system gallery.

Change Summary: In the constructed XML layout, a CardView element was instantiated. An interaction listener was configured to incite image selection from the system gallery upon user engagement. One method was delineated to spawn an intent for invoking the system gallery. One method was formulated to facilitate the decoding process of the QR code, utilizing the ZXing library, and subsequently rendering the output in PDF format.

Dependencies: ZXing library for QR code decoding.

Changed UI

Fixes #1101

Type of change

Just put an x in the [] which are valid.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

• [x] ./gradlew assembleDebug assembleRelease
• [x] ./gradlew checkstyle

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings

[codeclimate[bot]]

Code Climate has analyzed commit 38022863 and detected 3 issues on this pull request.

Here's the issue category breakdown:

Category	Count
Complexity	3

View more on Code Climate.

[Swati4star]

thank you for your contribution, but this feature is already implemented with https://github.com/Swati4star/Images-to-PDF/pull/1143