fix: add null checks in HtmlMovementMethod to prevent crashes

[graycreate]

Summary

• Adds comprehensive null checks in HtmlMovementMethod.onSpanClick() method
• Prevents NullPointerException when clicking on image spans
• Ensures safe comparison of image URLs

Problem

The app was crashing with the following stack trace from Google Play Console:

java.lang.NullPointerException:
  at me.ghui.v2er.widget.richtext.HtmlMovementMethod.onSpanClick (HtmlMovementMethod.java:215)
  at me.ghui.v2er.widget.richtext.HtmlMovementMethod.onTouchEvent (HtmlMovementMethod.java:257)

Root Cause

At line 215, the code was comparing currentImg.equals(imgs.get(i).getUrl()) without checking if:

1. imgs collection is null
2. currentImg is null
3. imgs.get(i) is null
4. imgs.get(i).getUrl() returns null

Any of these being null would cause a NullPointerException.

Solution

Added defensive null checks:

• Check if imgs and currentImg are not null before iterating
• Safely extract URL from image object with null check
• Use proper null-safe comparison

Test Plan

• Build project successfully
• Verify image click handling works when imgs is properly initialized
• Monitor crash reports after release to confirm fix

🤖 Generated with Claude Code

[Copilot]

Pull Request Overview

This PR fixes a critical NullPointerException crash in the HtmlMovementMethod's image click handling by adding comprehensive null safety checks. The crash was occurring when users clicked on image spans in the rich text widget.

• Adds null checks for the imgs collection and currentImg string before processing
• Implements safe URL extraction from image objects with null validation
• Wraps the image iteration logic in a null safety guard

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[Copilot]

This code will still throw a NullPointerException if imgUrl is null. The equals method should be called on the potentially null variable or use Objects.equals() for null-safe comparison. Consider changing to Objects.equals(currentImg, imgUrl) or imgUrl != null && imgUrl.equals(currentImg).