Merge pull request #21371 from akinwale/task-20836

src/libs/focusAndUpdateMultilineInputRange.js

@@ -0,0 +1,24 @@
+/**
+ * Focus a multiline text input and place the cursor at the end of the value (if there is a value in the input).
+ *
+ * When a multiline input contains a text value that goes beyond the scroll height, the cursor will be placed
+ * at the end of the text value, and automatically scroll the input field to this position after the field gains
+ * focus. This provides a better user experience in cases where the text in the field has to be edited. The auto-
+ * scroll behaviour works on all platforms except iOS native.
+ * See https://github.com/Expensify/App/issues/20836 for more details.
+ *
+ * @param {Object} input the input element
+ */
+export default function focusAndUpdateMultilineInputRange(input) {
+    if (!input) {
+        return;
+    }
+
+    input.focus();
+    if (input.value && input.setSelectionRange) {
+        const length = input.value.length;
+        input.setSelectionRange(length, length);
+        // eslint-disable-next-line no-param-reassign
+        input.scrollTop = input.scrollHeight;
+    }
+}

src/pages/tasks/NewTaskDescriptionPage.js

@@ -1,4 +1,4 @@
-import React, {useEffect, useRef, useState} from 'react';
+import React, {useRef} from 'react';
 import {View} from 'react-native';
 import {withOnyx} from 'react-native-onyx';
 import PropTypes from 'prop-types';
@@ -14,6 +14,7 @@ import TextInput from '../../components/TextInput';
 import Permissions from '../../libs/Permissions';
 import ROUTES from '../../ROUTES';
 import * as TaskUtils from '../../libs/actions/Task';
+import focusAndUpdateMultilineInputRange from '../../libs/focusAndUpdateMultilineInputRange';
 
 const propTypes = {
     /** Beta features list */
@@ -38,17 +39,6 @@ const defaultProps = {
 function NewTaskDescriptionPage(props) {
     const inputRef = useRef(null);
 
-    // The selection will be used to place the cursor at the end if there is prior text in the text input area
-    const [selection, setSelection] = useState({start: 0, end: 0});
-
-    // eslint-disable-next-line rulesdir/prefer-early-return
-    useEffect(() => {
-        if (props.task.description) {
-            const length = props.task.description.length;
-            setSelection({start: length, end: length});
-        }
-    }, [props.task.description]);
-
     // On submit, we want to call the assignTask function and wait to validate
     // the response
     const onSubmit = (values) => {
@@ -63,13 +53,7 @@ function NewTaskDescriptionPage(props) {
     return (
         <ScreenWrapper
             includeSafeAreaPaddingBottom={false}
-            onEntryTransitionEnd={() => {
-                if (!inputRef.current) {
-                    return;
-                }
-
-                inputRef.current.focus();
-            }}
+            onEntryTransitionEnd={() => focusAndUpdateMultilineInputRange(inputRef.current)}
         >
             <HeaderWithBackButton
                 title={props.translate('newTaskPage.description')}
@@ -93,10 +77,6 @@ function NewTaskDescriptionPage(props) {
                         submitOnEnter
                         containerStyles={[styles.autoGrowHeightMultilineInput]}
                         textAlignVertical="top"
-                        selection={selection}
-                        onSelectionChange={(e) => {
-                            setSelection(e.nativeEvent.selection);
-                        }}
                     />
                 </View>
             </Form>

src/pages/tasks/TaskDescriptionPage.js

@@ -1,4 +1,4 @@
-import React, {useCallback, useEffect, useRef, useState} from 'react';
+import React, {useCallback, useRef} from 'react';
 import PropTypes from 'prop-types';
 import {View} from 'react-native';
 import {withOnyx} from 'react-native-onyx';
@@ -12,6 +12,7 @@ import styles from '../../styles/styles';
 import compose from '../../libs/compose';
 import reportPropTypes from '../reportPropTypes';
 import * as TaskUtils from '../../libs/actions/Task';
+import focusAndUpdateMultilineInputRange from '../../libs/focusAndUpdateMultilineInputRange';
 
 const propTypes = {
     /** Current user session */
@@ -48,21 +49,10 @@ function TaskDescriptionPage(props) {
 
     const inputRef = useRef(null);
 
-    // Same as NewtaskDescriptionPage, use the selection to place the cursor correctly if there is prior text
-    const [selection, setSelection] = useState({start: 0, end: 0});
-
-    // eslint-disable-next-line rulesdir/prefer-early-return
-    useEffect(() => {
-        if (props.task.report && props.task.report.description) {
-            const length = props.task.report.description.length;
-            setSelection({start: length, end: length});
-        }
-    }, [props.task.report]);
-
     return (
         <ScreenWrapper
             includeSafeAreaPaddingBottom={false}
-            onEntryTransitionEnd={() => inputRef.current && inputRef.current.focus()}
+            onEntryTransitionEnd={() => focusAndUpdateMultilineInputRange(inputRef.current)}
         >
             <HeaderWithBackButton title={props.translate('newTaskPage.task')} />
             <Form
@@ -84,10 +74,6 @@ function TaskDescriptionPage(props) {
                         submitOnEnter
                         containerStyles={[styles.autoGrowHeightMultilineInput]}
                         textAlignVertical="top"
-                        selection={selection}
-                        onSelectionChange={(e) => {
-                            setSelection(e.nativeEvent.selection);
-                        }}
                     />
                 </View>
             </Form>