Ensure IME works on Android devices (#2580)

* simplify `isComposing` We had an issue #2409 where typing using an IME (Input Method Editor, E.g.: Japanese — Romaji) already submitted characters while the user was still composing the characters together. 1. Type `wa` 2. Expected result: `わ` 3. Actual result: `wあ` (where `あ` is the character `a`) This was solved by not triggering change events at all until the `compositionend` event was triggered. This worked fine for this use case. However this also meant that only at the end of your typing session (when you press `enter`/`space`) the actual value was submitted. Fast forward to today, we received a new issue #2575 where this behaviour completely broke on Android devices. Android _always_ use the IME APIs for handling input... if we think about our solution form above, it also means that while you are typing on an Android device no options are being filtered at all. The moment you hit enter/space the combobox will open and results will be filtered. This is where this fix comes in. The goals are simple: 1. Make it work 2. Try to make the current code simpler I started digging to see _why_ this `wあ` was even submitted. A normal input field doesn't do that?! We have some code that does the following things: 1. Sync the selected value with the `input` such that if you update the value from the outside, then the value in the `input` is up-to-date with the `displayValue` of that incoming value. 2. A fix for macOS VoiceOver to improve the VoiceOver experience when opening the `Combobox` component. This is done by manually resetting the value of the `input` field. 1. Keep track of the current value 2. Keep track of the current selection range (start/end) state 3. Reset the input to an empty string `''` 4. Restore the value to the captured value 5. Restore the selection range When you are typing, the input field doesn't have to update yet because typing doesn't cause an option to become the `selected` option, therefore it doesn't have to sync the value yet. So (1.) isn't the issue here. However, when you start typing, the Combobox should open and then we trigger the macOS VoiceOver fix. This is touching the `input` field because we change the value & selection. Because we touched the `input` while the user was still in a composing mode, it bailed and submitted whatever characters it had. This is the part that we don't want. Not applying the macOS VoiceOver fix while typing solves this issue. In addition, because _we_ are touching the input field, VoiceOver is acting normally. In hindsight, the solution is very simple: do not touch the input field when the user is typing. We still keep track whether the user `isComposing` so that we can bail on the default `Enter` behaviour (marking the current option as the selected option) because pressing `Enter` while composing should get out of the IME. Fixes: #2575 * update changelog
2023-07-06 14:35:35 +02:00
parent 17b2d34fe6
commit 00fdb7e3cd
4 changed files with 42 additions and 26 deletions
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0

 - Ensure the caret is in a consistent position when syncing the `Combobox.Input` value ([#2568](https://github.com/tailwindlabs/headlessui/pull/2568))
 - Improve "outside click" behaviour in combination with 3rd party libraries ([#2572](https://github.com/tailwindlabs/headlessui/pull/2572))
+- Ensure IME works on Android devices ([#2580](https://github.com/tailwindlabs/headlessui/pull/2580))

 ## [1.7.15] - 2023-06-01

@@ -778,9 +778,11 @@ function InputFn<
  //     - By clicking `outside` of the Combobox
  useWatch(
    ([currentDisplayValue, state], [oldCurrentDisplayValue, oldState]) => {
+      // When the user is typing, we want to not touch the `input` at all. Especially when they are
+      // using an IME, we don't want to mess with the input at all.
      if (isTyping.current) return
-      let input = data.inputRef.current

+      let input = data.inputRef.current
      if (!input) return

      if (oldState === ComboboxState.Open && state === ComboboxState.Closed) {
@@ -821,6 +823,10 @@ function InputFn<
  useWatch(
    ([newState], [oldState]) => {
      if (newState === ComboboxState.Open && oldState === ComboboxState.Closed) {
+        // When the user is typing, we want to not touch the `input` at all. Especially when they are
+        // using an IME, we don't want to mess with the input at all.
+        if (isTyping.current) return
+
        let input = data.inputRef.current
        if (!input) return

@@ -844,19 +850,12 @@ function InputFn<
  )

  let isComposing = useRef(false)
-  let composedChangeEvent = useRef<React.ChangeEvent<HTMLInputElement> | null>(null)
  let handleCompositionStart = useEvent(() => {
    isComposing.current = true
  })
  let handleCompositionEnd = useEvent(() => {
    d.nextFrame(() => {
      isComposing.current = false
-
-      if (composedChangeEvent.current) {
-        actions.openCombobox()
-        onChange?.(composedChangeEvent.current)
-        composedChangeEvent.current = null
-      }
    })
  })

@@ -885,6 +884,10 @@ function InputFn<
      case Keys.Enter:
        isTyping.current = false
        if (data.comboboxState !== ComboboxState.Open) return
+
+        // When the user is still in the middle of composing by using an IME, then we don't want to
+        // submit this value and close the Combobox yet. Instead, we will fallback to the default
+        // behaviour which is to "end" the composition.
        if (isComposing.current) return

        event.preventDefault()
@@ -983,12 +986,16 @@ function InputFn<
  })

  let handleChange = useEvent((event: React.ChangeEvent<HTMLInputElement>) => {
-    if (isComposing.current) {
-      composedChangeEvent.current = event
-      return
-    }
-    actions.openCombobox()
+    // Always call the onChange listener even if the user is still typing using an IME (Input Method
+    // Editor).
+    //
+    // The main issue is Android, where typing always uses the IME APIs. Just waiting until the
+    // compositionend event is fired to trigger an onChange is not enough, because then filtering
+    // options while typing won't work at all because we are still in "composing" mode.
    onChange?.(event)
+
+    // Open the combobox to show the results based on what the user has typed
+    actions.openCombobox()
  })

  let handleBlur = useEvent(() => {
@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Ensure the caret is in a consistent position when syncing the `Combobox.Input` value ([#2568](https://github.com/tailwindlabs/headlessui/pull/2568))
 - Improve "outside click" behaviour in combination with 3rd party libraries ([#2572](https://github.com/tailwindlabs/headlessui/pull/2572))
 - Improve performance of `Combobox` component ([#2574](https://github.com/tailwindlabs/headlessui/pull/2574))
+- Ensure IME works on Android devices ([#2580](https://github.com/tailwindlabs/headlessui/pull/2580))

 ## [1.7.14] - 2023-06-01

@@ -745,9 +745,11 @@ export let ComboboxInput = defineComponent({
      watch(
        [currentDisplayValue, api.comboboxState],
        ([currentDisplayValue, state], [oldCurrentDisplayValue, oldState]) => {
+          // When the user is typing, we want to not touch the `input` at all. Especially when they
+          // are using an IME, we don't want to mess with the input at all.
          if (isTyping.value) return
-          let input = dom(api.inputRef)

+          let input = dom(api.inputRef)
          if (!input) return

          if (oldState === ComboboxStates.Open && state === ComboboxStates.Closed) {
@@ -788,6 +790,10 @@ export let ComboboxInput = defineComponent({
      // already in an open state.
      watch([api.comboboxState], ([newState], [oldState]) => {
        if (newState === ComboboxStates.Open && oldState === ComboboxStates.Closed) {
+          // When the user is typing, we want to not touch the `input` at all. Especially when they
+          // are using an IME, we don't want to mess with the input at all.
+          if (isTyping.value) return
+
          let input = dom(api.inputRef)
          if (!input) return

@@ -810,19 +816,12 @@ export let ComboboxInput = defineComponent({
    })

    let isComposing = ref(false)
-    let composedChangeEvent = ref<(Event & { target: HTMLInputElement }) | null>(null)
    function handleCompositionstart() {
      isComposing.value = true
    }
    function handleCompositionend() {
      disposables().nextFrame(() => {
        isComposing.value = false
-
-        if (composedChangeEvent.value) {
-          api.openCombobox()
-          emit('change', composedChangeEvent.value)
-          composedChangeEvent.value = null
-        }
      })
    }

@@ -852,6 +851,10 @@ export let ComboboxInput = defineComponent({
        case Keys.Enter:
          isTyping.value = false
          if (api.comboboxState.value !== ComboboxStates.Open) return
+
+          // When the user is still in the middle of composing by using an IME, then we don't want
+          // to submit this value and close the Combobox yet. Instead, we will fallback to the
+          // default behaviour which is to "end" the composition.
          if (isComposing.value) return

          event.preventDefault()
@@ -945,12 +948,16 @@ export let ComboboxInput = defineComponent({
    }

    function handleInput(event: Event & { target: HTMLInputElement }) {
-      if (isComposing.value) {
-        composedChangeEvent.value = event
-        return
-      }
-      api.openCombobox()
+      // Always call the onChange listener even if the user is still typing using an IME (Input Method
+      // Editor).
+      //
+      // The main issue is Android, where typing always uses the IME APIs. Just waiting until the
+      // compositionend event is fired to trigger an onChange is not enough, because then filtering
+      // options while typing won't work at all because we are still in "composing" mode.
      emit('change', event)
+
+      // Open the combobox to show the results based on what the user has typed
+      api.openCombobox()
    }

    function handleBlur() {