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Workaround for Unity's inability to keep an input field selected when you click a button
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// Released under MIT License | |
using System.Reflection; | |
using TMPro; | |
using UnityEngine; | |
using UnityEngine.EventSystems; | |
using UnityEngine.UI; | |
// Workaround for Unity's inability to keep an input field selected when you click a button. | |
// Call ReactivateInputField to immediately activate and restore caret position/selection. | |
// This class also tracks the state of the last selected input field in Update, allowing easier restoration of the input field when it becomes deselected. | |
// Common use cases are to: | |
// - restore it immediately when it becomes deselected (in the callback for inputField.onEndEdit) | |
// - restore it immediately once the user clicks a particular button | |
// - restore it once the user returns to a particular state in your app | |
public class InputFieldActivationRestorer : MonoSingleton<InputFieldActivationRestorer> { | |
// The current restorable settings | |
public RestorableInputFieldSettings lastSelectedInputFieldSettings; | |
public bool lastSelectedInputFieldIsCurrentlySelected => lastSelectedInputFieldSettings.isRestorable && EventSystem.current != null && EventSystem.current.currentSelectedGameObject == lastSelectedInputFieldSettings.restorableGameObject; | |
// This struct contains all the properties that can be restored | |
[System.Serializable] | |
public struct RestorableInputFieldSettings { | |
public bool isRestorable => restorableInputField != null || restorableTMPInputField != null; | |
public GameObject restorableGameObject { | |
get { | |
if (restorableInputField != null) return restorableInputField.gameObject; | |
else if (restorableTMPInputField != null) return restorableTMPInputField.gameObject; | |
else return null; | |
} | |
} | |
public InputField restorableInputField; | |
public TMP_InputField restorableTMPInputField; | |
public int caretPosition; | |
public int selectionAnchorPosition; | |
public int selectionFocusPosition; | |
// Sets the input field to be restored automatically using whatever input field is currently selected | |
public static RestorableInputFieldSettings FromCurrentSelection() { | |
var selectedInputField = GetSelectedUGUIInputField(); | |
if (selectedInputField != null) { | |
return new RestorableInputFieldSettings(selectedInputField); | |
} | |
var selectedTMPInputField = GetSelectedTMPInputField(); | |
if(selectedTMPInputField != null) { | |
return new RestorableInputFieldSettings(selectedTMPInputField); | |
} | |
return default; | |
static TMP_InputField GetSelectedTMPInputField () { | |
if(EventSystem.current == null) return null; | |
var selectedGO = EventSystem.current.currentSelectedGameObject; | |
if (selectedGO == null) return null; | |
var inputField = selectedGO.GetComponentInParent<TMP_InputField>(); | |
return inputField != null && inputField.isFocused ? inputField : null; | |
} | |
static InputField GetSelectedUGUIInputField () { | |
if(EventSystem.current == null) return null; | |
var selectedGO = EventSystem.current.currentSelectedGameObject; | |
if (selectedGO == null) return null; | |
var inputField = selectedGO.GetComponentInParent<InputField>(); | |
return inputField != null && inputField.isFocused ? inputField : null; | |
} | |
} | |
public RestorableInputFieldSettings(InputField inputField) { | |
restorableInputField = inputField; | |
restorableTMPInputField = null; | |
caretPosition = inputField.caretPosition; | |
selectionAnchorPosition = inputField.selectionAnchorPosition; | |
selectionFocusPosition = inputField.selectionFocusPosition; | |
} | |
public RestorableInputFieldSettings(TMP_InputField tmpInputField) { | |
restorableInputField = null; | |
restorableTMPInputField = tmpInputField; | |
caretPosition = tmpInputField.caretPosition; | |
selectionAnchorPosition = tmpInputField.selectionAnchorPosition; | |
selectionFocusPosition = tmpInputField.selectionFocusPosition; | |
} | |
public override bool Equals(object obj) { | |
if (obj == null || GetType() != obj.GetType()) { | |
return false; | |
} | |
RestorableInputFieldSettings other = (RestorableInputFieldSettings)obj; | |
return (restorableInputField == other.restorableInputField && | |
restorableTMPInputField == other.restorableTMPInputField && | |
caretPosition == other.caretPosition && | |
selectionAnchorPosition == other.selectionAnchorPosition && | |
selectionFocusPosition == other.selectionFocusPosition); | |
} | |
public override int GetHashCode() { | |
unchecked { | |
int hash = 17; | |
hash = hash * 23 + (restorableInputField != null ? restorableInputField.GetHashCode() : 0); | |
hash = hash * 23 + (restorableTMPInputField != null ? restorableTMPInputField.GetHashCode() : 0); | |
hash = hash * 23 + caretPosition.GetHashCode(); | |
hash = hash * 23 + selectionAnchorPosition.GetHashCode(); | |
hash = hash * 23 + selectionFocusPosition.GetHashCode(); | |
return hash; | |
} | |
} | |
} | |
public void ReactivateLastSelectedInputField() { | |
ReactivateInputField(lastSelectedInputFieldSettings); | |
} | |
// Selects the previously selected input field and restores the selection state. | |
public static void ReactivateInputField(RestorableInputFieldSettings restorableState) { | |
if (!restorableState.isRestorable) return; | |
// Copy the struct just in case something here causes it to be updated while we're restoring it | |
if (restorableState.restorableInputField != null) { | |
restorableState.restorableInputField.ActivateInputField(); | |
// This forces TMP to immediately set itself selectable again. | |
MethodInfo mInfoMethod = typeof(InputField).GetMethod("LateUpdate", BindingFlags.Instance | BindingFlags.NonPublic); | |
mInfoMethod.Invoke(restorableState.restorableInputField, null); | |
} | |
else if (restorableState.restorableTMPInputField != null) { | |
restorableState.restorableTMPInputField.ActivateInputField(); | |
// This forces TMP to immediately set itself selectable again. | |
MethodInfo mInfoMethod = typeof(TMP_InputField).GetMethod("LateUpdate", BindingFlags.Instance | BindingFlags.NonPublic); | |
mInfoMethod.Invoke(restorableState.restorableTMPInputField, null); | |
} | |
if (restorableState.restorableInputField != null && EventSystem.current.currentSelectedGameObject == restorableState.restorableInputField.gameObject) { | |
restorableState.restorableInputField.caretPosition = restorableState.caretPosition; | |
restorableState.restorableInputField.selectionAnchorPosition = restorableState.selectionAnchorPosition; | |
restorableState.restorableInputField.selectionFocusPosition = restorableState.selectionFocusPosition; | |
restorableState.restorableInputField.ForceLabelUpdate(); | |
} | |
else if (restorableState.restorableTMPInputField != null && EventSystem.current.currentSelectedGameObject == restorableState.restorableTMPInputField.gameObject) { | |
restorableState.restorableTMPInputField.caretPosition = restorableState.caretPosition; | |
restorableState.restorableTMPInputField.selectionAnchorPosition = restorableState.selectionAnchorPosition; | |
restorableState.restorableTMPInputField.selectionFocusPosition = restorableState.selectionFocusPosition; | |
restorableState.restorableTMPInputField.ForceLabelUpdate(); | |
} | |
} | |
void Update() { | |
if (EventSystem.current != null) { | |
var currentSelectionState = RestorableInputFieldSettings.FromCurrentSelection(); | |
if (currentSelectionState.isRestorable) lastSelectedInputFieldSettings = currentSelectionState; | |
} | |
} | |
} |
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MIT is fine by me. Edited the snippet!