If a controller isn't provided in the constructor, the `controller` member is `null`. This makes `PageView` and its `controller` property consistent with other widgets.
- Who is affected
- Applications and packages relying on the previous behaviour or signature. Code that uses PageView.
- Practical impact
- Behaviour or API differences that can break builds or change runtime behaviour.
- What action should I take?
- Follow the official migration guide below, update affected call sites, run `dart fix --apply` where a fix is available, then run your tests.
APIs mentioned:PageView
Before and after (from the official guide)
dart+1−1
Before
| 1 | − | pageView.controller.page |
After
| 1 | + | pageView.controller!.page |
Raw before / after
pageView.controller.page
pageView.controller!.page
Official migration guide (excerpt, © The Flutter Authors, CC BY 3.0)
Before:
pageView.controller.pageAfter:
pageView.controller!.pageMigration assistantAI-generated · grounded in cited sources
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AI_PROVIDER (for example to openai-compatible with a local Ollama or LM Studio endpoint) to enable grounded explanations. Everything else on this page works without an AI provider.Official migration guide·Verified classification (95%)
Listed in the official breaking-changes index (docs.flutter.dev/release/breaking-changes).
An official announcement or migration guide documents an intended behaviour or API change. A verified source change (git diff) shows code changed but does not by itself prove a public API is breaking. AI interpretations are labelled and never used to classify a change.
Validation warnings
api-symbols: {"unresolved":["PageView"]}
- Source commit
- b3045439b7c0
- Source last updated
- Oct 21, 2026
- Last synchronized
- Oct 21, 2026
- Publication status
- published
Publication history
- Oct 21, 2026, 8:31 PM: new → published (ingestion) — Backed by an official breaking-change/migration guide.
AI explanationAI-generated · grounded in cited sources
AI explanations are not configured
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AI_PROVIDER (for example to openai-compatible with a local Ollama or LM Studio endpoint) to enable grounded explanations. Everything else on this page works without an AI provider.Was this useful?