fix: app crash when download asset

[alexandreferris]

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• The PR Title

  • conforms to the style of semantic commits messages¹ supported in Wire's Github Workflow²
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What's new in this PR?

Issues

When downloading an asset from the context menu, we were not checking for saving to external permission when user was on Android 9 (API level 28) or lower.

Causes (Optional)

We were not checking permissions.

Solutions

Change downloadAssetExternally to downloadOrFetchAssetAndShowDialog so there is a Dialog handling everything:

• Checking for device API Level + Permissions
• Save
• Open
• Cancel

And showing a snackbar when successfully saved.

Testing

How to Test

• Open App
• Open Conversation
• Receive an Image or Audio file
• do not grant file storage permission to app before-hand
• Long click on Image/Audio file
• Select Download from the context menu
• A new Dialog should popup asking if you want to Save/Open/Cancel, if Save then asking permission will be shown

[github-actions]

Test Results

542 tests   541 ✔️  27s ⏱️
  77 suites      1 💤
  77 files        0 ❌

Results for commit 7e4181c.

[github-actions]

APKs built during tests are available here. Scroll down to Artifacts!

[AndroidBob]

Build 1046 succeeded.

The build produced the following APK's:

• com.wire.android-v4.3.0(7280034)(7280034)-staging-compat.apk