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• Platform android-30, build-tools 30.0.2
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解释
- 只有一个按钮
- 按下按钮时，按钮处于
State A - 当指针在屏幕上拖动时，该按钮不会触发任何其他事件
- 当指针从屏幕上消失时，即在屏幕上拖动或指针与屏幕不一致时，按钮处于
State B
我尝试了什么
- 使用手势检测器并为方法
onTapDown和onTapUp创建函数 - 这就是我得到的
══╡ EXCEPTION CAUGHT BY GESTURE ╞═══════════════════════════════════════════════════════════════════
The following RangeError was thrown while handling a gesture:
Value not in range: 0
When the exception was thrown, this was the stack:
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 236:49 throw_
dart-sdk/lib/_internal/js_dev_runtime/private/js_string.dart 171:66 substring]
packages/safer/controllers/number_pad_controller.dart 37:31 deleteInput
packages/flutter/src/material/ink_well.dart 991:14 [_handleTap]
packages/flutter/src/gestures/recognizer.dart 182:24 invokeCallback
packages/flutter/src/gestures/tap.dart 607:48 handleTapUp
packages/flutter/src/gestures/tap.dart 296:5 [_checkUp]
packages/flutter/src/gestures/tap.dart 267:7 acceptGesture
packages/flutter/src/gestures/arena.dart 157:12 sweep
packages/flutter/src/gestures/binding.dart 385:20 handleEvent
packages/flutter/src/gestures/binding.dart 361:14 dispatchEvent
packages/flutter/src/rendering/binding.dart 278:11 dispatchEvent
packages/flutter/src/gestures/binding.dart 316:7 [_handlePointerEventImmediately]
packages/flutter/src/gestures/binding.dart 280:5 handlePointerEvent
packages/flutter/src/gestures/binding.dart 238:7 [_flushPointerEventQueue]
packages/flutter/src/gestures/binding.dart 221:32 [_handlePointerDataPacket]
lib/_engine/engine/platform_dispatcher.dart 911:13 invoke1
lib/_engine/engine/platform_dispatcher.dart 170:5 invokeOnPointerDataPacket
lib/_engine/engine/pointer_binding.dart 128:39 [_onPointerData]
lib/_engine/engine/pointer_binding.dart 553:18 <fn>
lib/_engine/engine/pointer_binding.dart 506:21 <fn>
lib/_engine/engine/pointer_binding.dart 214:16 <fn>
Handler: "onTap"
Recognizer:
TapGestureRecognizer#87a24
════════════════════════════════════════════════════════════════════════════════════════════════════
Another exception was thrown: RangeError: Value not in range: 0
- 但是，它从
State A移动到State B - 但是，当我在保持按钮不变的情况下将指针移出按钮，然后从屏幕上移除指针时，按钮不会变为
State B，而是保持在State A
问题
- 我想了解解决此问题所需的建议
- 或者任何我认为有助于解决这个问题的补充资源
事实证明我可以绕过这个问题。
- 将
onLongPress方法设置为State A - 将
onLongPressEnd方法设置为State B