diff --git a/pages/picking/picking.vue b/pages/picking/picking.vue
index b893c0f..74cb8b0 100644
--- a/pages/picking/picking.vue
+++ b/pages/picking/picking.vue
@@ -282,7 +282,7 @@
 		<uni-popup ref="submitConfirmPopup" type="bottom" background-color="#ffffff" border-radius="16px 16px 0 0" :is-mask-click="true" @change="handleOverlayChange('submitConfirm', $event)">
 			<view class="modal-sheet decision-modal submit-decision-modal" role="dialog" aria-modal="true" aria-label="确认未完成提交" @tap.stop>
 				<PopupHeader :title="`仍有 ${summary.pending} 件未完成`" tone="danger" @close="closeOverlay" />
-				<text class="decision-desc submit-decision-desc">确认提交后，以下待拣商品会被明确标记为“未拣出”，本次演示提交不可撤销。</text>
+				<text class="decision-desc submit-decision-desc">确认提交后，以下待拣商品会标记为“未拣出”，并记录所选原因。</text>
 				<view class="pending-sku-list">
 					<text v-for="item in pendingItems.slice(0, 3)" :key="item.id">{{ item.location ? `${item.sku} · ${item.location}` : item.sku }}</text>
 					<text v-if="pendingItems.length > 3">另有 {{ pendingItems.length - 3 }} 件</text>
@@ -293,7 +293,7 @@
 				</view>
 				<view class="modal-actions submit-decision-actions">
 					<button class="modal-cancel-btn" @tap="closeOverlay">继续拣货</button>
-					<button class="modal-confirm-btn danger-confirm" :disabled="!selectedIncompleteReason" @tap="confirmIncompleteSubmit">确认未拣并提交</button>
+					<button class="modal-confirm-btn danger-confirm" :disabled="submitting || !selectedIncompleteReason" @tap="confirmIncompleteSubmit">{{ submitting ? '正在提交…' : '确认未拣并提交' }}</button>
 				</view>
 			</view>
 		</uni-popup>
@@ -571,12 +571,15 @@
 					return
 				}
 				if (this._showRefreshPromise) return this._showRefreshPromise
-				this._showRefreshPromise = (async () => {
+				const showGeneration = this.taskRequestId
+				const refreshPromise = (async () => {
 					await this.refreshAvailableBoxes()
+					if (!this._pageVisible || showGeneration !== this.taskRequestId) return
 					await this.syncRemoteTask()
 				})()
-				try { await this._showRefreshPromise }
-				finally { this._showRefreshPromise = null }
+				this._showRefreshPromise = refreshPromise
+				try { await refreshPromise }
+				finally { if (this._showRefreshPromise === refreshPromise) this._showRefreshPromise = null }
 		},
 		onHide() {
 				this._pageVisible = false
@@ -584,10 +587,11 @@
 					this.evidencePreviewOpening = false
 					this.evidencePreviewReturning = true
 				}
+				if (!this.cameraPicking && !this.evidencePreviewReturning) this.invalidateTaskSync()
 				this.stopHardwareScanner()
 		},
-		onUnload() { this.stopHardwareScanner(); this.persistSession(); this.clearTimers() },
-		beforeUnmount() { this.stopHardwareScanner(); this.clearTimers() },
+		onUnload() { this._pageVisible = false; this.invalidateTaskSync(); this.evidenceContextId++; this.stopHardwareScanner(); this.persistSession(); this.clearTimers() },
+		beforeUnmount() { this._pageVisible = false; this.invalidateTaskSync(); this.stopHardwareScanner(); this.clearTimers() },
 		onBackPress() {
 			if (this.activeOverlay) { this.closeOverlay(); return true }
 			if (this.boxDropdownOpen) { this.boxDropdownOpen = false; return true }
@@ -595,6 +599,11 @@
 			return false
 		},
 		methods: {
+			invalidateTaskSync() { this.taskRequestId++; this.remoteLoading = false; this._showRefreshPromise = null },
+			isTaskSyncActive(requestId, taskId) {
+				return this._pageVisible === true && requestId === this.taskRequestId
+					&& String(this.remoteTaskId || this.currentBox.taskId) === String(taskId)
+			},
 			containerReference,
 			isSelectableTask(task) {
 				return Boolean(task?.recordStatus === 'ACTIVE'
@@ -1090,7 +1099,7 @@
 				return ''
 			},
 			async syncRemoteTask() {
-				if (!session.token) return
+				if (!session.token || !this._pageVisible) return
 				const requestedTaskId = this.remoteTaskId || this.currentBox.taskId
 				if (!requestedTaskId) { this.remoteError = '当前没有可进入的拣货任务，请返回任务列表刷新'; return }
 				this.rememberEvidenceDraft()
@@ -1114,7 +1123,7 @@
 				try {
 					const warehouseId = this.currentBox.warehouseId
 					const task = await getContainerPickingTask(selector, warehouseId)
-					if (requestId !== this.taskRequestId) return
+					if (!this.isTaskSyncActive(requestId, requestedTaskId)) return
 					if (!task) throw new Error('服务端未返回当前拣货任务')
 					if (this.isMergedContainerRecord(task)) {
 						this.clearMergedTask(task, previousIdentity)
@@ -1181,9 +1190,10 @@
 					if (remoteTask.workflowStatus !== 'AWAITING_REVIEW' && this.assignmentVersion === null) throw new Error('任务领取状态尚未同步，请刷新重试')
 					let claimed = null
 					if (remoteTask.workflowStatus === 'UNASSIGNED') {
+						if (!this.isTaskSyncActive(requestId, requestedTaskId)) return
 						const operationId = `claim-${session.currentUser?.id || 'operator'}-${this.remoteTaskId}-${task.loadingPlanId}-${task.containerBookingId}`
 						claimed = await claimContainerPickingTask(this.remoteTaskId, this.assignmentVersion, operationId)
-						if (requestId !== this.taskRequestId) return
+						if (!this.isTaskSyncActive(requestId, requestedTaskId)) return
 					} else if (remoteTask.workflowStatus === 'IN_PROGRESS') {
 						const assigneeId = remoteTask.assignment?.assigneeId
 						if (!assigneeId || String(assigneeId) !== String(session.currentUser?.id || '')) throw new Error('当前任务已由其他作业员领取，请返回任务列表刷新')
@@ -1215,9 +1225,10 @@
 						if (addedItemIds.length) this.showToast(`已同步 ${addedItemIds.length} 条新增待拣明细`, 'warning')
 					}
 					await this.loadLoadingEvidence()
+					if (!this.isTaskSyncActive(requestId, requestedTaskId)) return
 					if (this.loadingStageReady) this.activeStage = 'evidence'
 				} catch (error) {
-					if (requestId !== this.taskRequestId) return
+					if (!this.isTaskSyncActive(requestId, requestedTaskId)) return
 					this.debugSubmit('refresh.error', { requestId, message: error.message || '', code: error.code || '', statusCode: error.statusCode || '', requestIdFromServer: error.requestId || '', traceId: error.traceId || '' })
 					this.remoteError = error.network ? '网络不可用，无法开始拣货，恢复网络后请重试' : this.remoteFailureMessage(error, '任务同步失败')
 				} finally { if (requestId === this.taskRequestId) this.remoteLoading = false }
@@ -1675,10 +1686,11 @@
 				this.performSubmit()
 			},
 			confirmIncompleteSubmit() {
-				if (!this.selectedIncompleteReason) return
-				this.performSubmit(this.selectedIncompleteReason)
+				if (this.submitting || !this.selectedIncompleteReason) return
+				return this.performSubmit(this.selectedIncompleteReason)
 			},
 			async performSubmit(incompleteReason = '') {
+				if (this.submitting) return
 				const beforeSubmit = this.summary
 				const remoteRequired = Boolean(session.token)
 				this.remoteError = ''
diff --git a/tests/page-contract.test.mjs b/tests/page-contract.test.mjs
index f525ef9..59f0008 100644
--- a/tests/page-contract.test.mjs
+++ b/tests/page-contract.test.mjs
@@ -292,7 +292,10 @@ test('picking session persists per task identity and clears on logout', async ()
 	assert.match(store, /savePickingSession/)
 	assert.match(store, /resetPickingSession/)
 	assert.match(session, /signOut\(\)[\s\S]*?resetPickingSession\(\)/)
-	assert.match(page, /onUnload\(\) \{ this\.stopHardwareScanner\(\); this\.persistSession\(\)/)
+	const unload = page.match(/onUnload\(\) \{([^}]+)\}/)?.[1] || ''
+	assert.match(unload, /this\.stopHardwareScanner\(\)/)
+	assert.match(unload, /this\.persistSession\(\)/)
+	assert.match(unload, /this\.invalidateTaskSync\(\)/)
 })
 
 test('shared visual contracts preserve accessible PDA targets', async () => {
diff --git a/tests/picking-refresh-route.test.mjs b/tests/picking-refresh-route.test.mjs
index 128999d..6a7d078 100644
--- a/tests/picking-refresh-route.test.mjs
+++ b/tests/picking-refresh-route.test.mjs
@@ -36,12 +36,14 @@ test('duplicate onShow shares one load chain while background return refreshes a
 	const page = await read('../pages/picking/picking.vue')
 	const show = page.match(/async onShow\(\) \{[\s\S]*?\r?\n\t\t\},/)?.[0]
 	const hide = page.match(/onHide\(\) \{[\s\S]*?\r?\n\t\t\},/)?.[0]
-	assert.ok(show && hide)
-	const hooks = new Function('requireSession', 'session', `return ({${show}${hide}})`)(() => true, { currentUser: { id: '7' } })
+	const invalidate = page.match(/invalidateTaskSync\(\) \{[^\r\n]+\},/)?.[0]
+	assert.ok(show && hide && invalidate)
+	const hooks = new Function('requireSession', 'session', `return ({${show}${hide}${invalidate}})`)(() => true, { currentUser: { id: '7' } })
 	const calls = []
 	let release
 	const pending = new Promise((resolve) => { release = resolve })
-	const context = { startHardwareScanner() {}, stopHardwareScanner() {}, async refreshAvailableBoxes() { calls.push('pending'); await pending }, async syncRemoteTask() { calls.push('detail+evidence') } }
+	const context = { taskRequestId: 0, invalidateTaskSync: hooks.invalidateTaskSync,
+		startHardwareScanner() {}, stopHardwareScanner() {}, async refreshAvailableBoxes() { calls.push('pending'); await pending }, async syncRemoteTask() { calls.push('detail+evidence') } }
 	const first = hooks.onShow.call(context)
 	const duplicate = hooks.onShow.call(context)
 	assert.deepEqual(calls, ['pending'])
@@ -51,6 +53,9 @@ test('duplicate onShow shares one load chain while background return refreshes a
 	await hooks.onShow.call(context)
 	assert.equal(calls.length, 2)
 	hooks.onHide.call(context)
+	assert.equal(context.taskRequestId, 1)
+	assert.equal(context.remoteLoading, false)
+	assert.equal(context._showRefreshPromise, null)
 	await hooks.onShow.call(context)
 	assert.deepEqual(calls, ['pending', 'detail+evidence', 'pending', 'detail+evidence'])
 	const onLoad = page.match(/onLoad\(options = \{\}\) \{[\s\S]*?\r?\n\t\t\},/)?.[0]
diff --git a/tests/picking-request-lifecycle.test.mjs b/tests/picking-request-lifecycle.test.mjs
new file mode 100644
index 0000000..858eea4
--- /dev/null
+++ b/tests/picking-request-lifecycle.test.mjs
@@ -0,0 +1,118 @@
+import test from 'node:test'
+import assert from 'node:assert/strict'
+import vm from 'node:vm'
+import { readFile } from 'node:fs/promises'
+
+const source = await readFile(new URL('../pages/picking/picking.vue', import.meta.url), 'utf8')
+const script = source.match(/<script>([\s\S]*?)<\/script>/)[1]
+const noop = () => {}
+const deferred = () => { let resolve, reject; const promise = new Promise((yes, no) => { resolve = yes; reject = no }); return { promise, resolve, reject } }
+function mount(overrides = {}, state = {}) {
+  const globals = { console, setTimeout, clearTimeout }
+  for (const match of script.matchAll(/import\s+(.*?)\s+from\s+['"][^'"]+['"]/g)) {
+    for (const name of match[1].replace(/[{}]/g, '').split(',').map(value => value.trim()).filter(Boolean)) globals[name] = noop
+  }
+  Object.assign(globals, { session: { token: 'offline', currentUser: { id: 'operator' } }, requireSession: () => true,
+    ITEM_STATUS: { PICKED: 'PICKED', PARTIAL: 'PARTIAL', SKIPPED: 'SKIPPED' },
+    isSealedPalletItem: () => false, isRemoteReady: () => true, stableOperationId: () => 'stable-operation',
+    stableTaskOperationIdentity: () => ({}), normalizePickingTask: value => value,
+    createItemStates: () => ({}), summarizeInventoryResources: () => ({}),
+    submitStates: () => ({ states: {}, autoSkippedIds: [] }), getPickSummary: () => ({}), ...overrides })
+  vm.createContext(globals)
+  vm.runInContext(script.replace(/^\s*import .*$/gm, '').replace('export default', 'globalThis.page ='), globals)
+  const page = globals.page
+  const ctx = { taskRequestId: 0, _pageVisible: true, evidenceContextId: 0, remoteTaskId: 'task',
+    currentBox: { taskId: 'task', warehouseId: 'warehouse', inboundId: 'inbound', loadingPlanId: 'plan', containerBookingId: 'container',
+      items: [{ id: 'item', taskItemId: 'item', itemStatus: 'PENDING', qty: 2, version: 0 }] },
+    evidenceFiles: {}, evidenceIdentity: null, sealNo: '', pickingVersion: 1,
+    summary: { pending: 1 }, itemStates: {}, partialQuantities: {}, completedBoxes: {},
+    selectedIncompleteReason: '现场未找到', submitting: false, loadingStageReady: false, pickingCompleted: false }
+  for (const [name, method] of Object.entries(page.methods)) ctx[name] = method.bind(ctx)
+  Object.assign(ctx, { rememberEvidenceDraft: noop, draftIdentity: () => ({}), resetEvidenceState: noop,
+    debugSubmit: noop, debugEvidence: noop, showToast: noop, persistSession: noop, clearTimers: noop,
+    stopHardwareScanner: noop, startHardwareScanner: noop, captureEvidenceIdentity: () => ({}),
+    restoreEvidenceDraft: noop, isSameEvidenceIdentity: () => false, restoreRemoteDraft: noop,
+    itemState: () => 'PENDING', saveCurrentBoxDraft: noop, openOverlay: noop,
+    isTaskConflict: () => false, remoteFailureMessage: () => 'failed', ...state })
+  return { page, ctx }
+}
+
+test('double confirmation and direct reentry send exactly one snapshot and one batch', async () => {
+  const snapshot = deferred(), batch = deferred(); let snapshots = 0, batches = 0
+  const { ctx } = mount({ submitContainerPickingBatch: async () => { batches++; return batch.promise } }, {
+    refreshInventorySnapshot: async () => { snapshots++; return snapshot.promise },
+    syncRemoteTask: async function () { this.pickingCompleted = true },
+  })
+  const first = ctx.confirmIncompleteSubmit()
+  ctx.confirmIncompleteSubmit(); await ctx.performSubmit('现场未找到')
+  assert.equal(ctx.submitting, true); assert.equal(snapshots, 1); assert.equal(batches, 0)
+  snapshot.resolve({ snapshotToken: 'snapshot' }); await new Promise(setImmediate)
+  ctx.confirmIncompleteSubmit(); assert.equal(batches, 1)
+  batch.resolve(null); await first
+  assert.equal(snapshots, 1); assert.equal(batches, 1); assert.equal(ctx.submitting, false)
+  assert.match(source, /:disabled="submitting \|\| !selectedIncompleteReason"/)
+})
+
+test('failed request releases submit guard and retry keeps operation identity', async () => {
+  const keys = []; let snapshots = 0
+  const { ctx } = mount({ submitContainerPickingBatch: async (_task, _actions, options) => { keys.push(options.operationId); throw new Error('network') } }, {
+    refreshInventorySnapshot: async () => { snapshots++; return { snapshotToken: 'snapshot' } },
+  })
+  await ctx.confirmIncompleteSubmit(); assert.equal(ctx.submitting, false)
+  await ctx.confirmIncompleteSubmit()
+  assert.equal(snapshots, 2); assert.deepEqual(keys, ['stable-operation', 'stable-operation'])
+})
+
+const task = () => ({ taskId: 'task', recordStatus: 'ACTIVE', loadingPlanId: 'plan', containerBookingId: 'container',
+  currentContainerNo: 'TEST', version: 1, workflowStatus: 'UNASSIGNED', items: [{ id: 'item', packageCount: 2, itemStatus: 'PENDING' }] })
+for (const hook of ['onHide', 'onUnload']) {
+  test(`${hook} while detail is pending prevents claim and evidence requests`, async () => {
+    const detail = deferred(); let claims = 0, evidence = 0
+    const { page, ctx } = mount({ getContainerPickingTask: () => detail.promise,
+      claimContainerPickingTask: async () => { claims++; return {} } }, { loadLoadingEvidence: async () => { evidence++ } })
+    const pending = ctx.syncRemoteTask(); page[hook].call(ctx); detail.resolve(task()); await pending
+    assert.equal(claims, 0); assert.equal(evidence, 0); assert.equal(ctx.remoteLoading, false)
+  })
+}
+
+test('unload during already-sent claim prevents its response from loading evidence', async () => {
+  const claim = deferred(); let claims = 0, evidence = 0
+  const { page, ctx } = mount({ getContainerPickingTask: async () => task(),
+    claimContainerPickingTask: () => { claims++; return claim.promise } }, { loadLoadingEvidence: async () => { evidence++ } })
+  const pending = ctx.syncRemoteTask(); await new Promise(setImmediate)
+  assert.equal(claims, 1, ctx.remoteError)
+  page.onUnload.call(ctx); claim.resolve({ workflowStatus: 'IN_PROGRESS', version: 2 }); await pending
+  assert.equal(evidence, 0); assert.equal(ctx.remotePick, undefined)
+})
+
+test('unload during onShow list fetch prevents starting task sync afterward', async () => {
+  const list = deferred(); let syncs = 0
+  const { page, ctx } = mount({}, { _pageVisible: false, refreshAvailableBoxes: () => list.promise,
+    syncRemoteTask: async () => { syncs++ } })
+  const pending = page.onShow.call(ctx); page.onUnload.call(ctx); list.resolve(); await pending
+  assert.equal(syncs, 0)
+})
+
+test('old hidden onShow cannot clear a newer visible refresh or start another sync', async () => {
+  const oldList = deferred(), newList = deferred(); let lists = 0, syncs = 0
+  const { page, ctx } = mount({}, { _pageVisible: false,
+    refreshAvailableBoxes: () => (++lists === 1 ? oldList.promise : newList.promise),
+    syncRemoteTask: async () => { syncs++ } })
+  const oldShow = page.onShow.call(ctx)
+  page.onHide.call(ctx)
+  const newShow = page.onShow.call(ctx), currentPromise = ctx._showRefreshPromise
+  oldList.resolve(); await oldShow
+  assert.equal(syncs, 0); assert.equal(ctx._showRefreshPromise, currentPromise)
+  newList.resolve(); await newShow
+  assert.equal(syncs, 1); assert.equal(ctx._showRefreshPromise, null)
+})
+
+for (const mode of ['camera', 'preview']) {
+  test(`${mode} hide/return keeps existing exception and avoids refresh`, async () => {
+    let refreshes = 0
+    const { page, ctx } = mount({}, { cameraPicking: mode === 'camera', evidencePreviewOpening: mode === 'preview',
+      refreshAvailableBoxes: async () => { refreshes++ }, syncRemoteTask: async () => { refreshes++ } })
+    page.onHide.call(ctx); assert.equal(ctx.taskRequestId, 0)
+    await page.onShow.call(ctx); assert.equal(refreshes, 0); assert.equal(ctx._pageVisible, true)
+  })
+}