586 lines
21 KiB
Objective-C
586 lines
21 KiB
Objective-C
/**
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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#import "RCTBaseTextInputView.h"
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#import <React/RCTAccessibilityManager.h>
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#import <React/RCTBridge.h>
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#import <React/RCTConvert.h>
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#import <React/RCTEventDispatcher.h>
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#import <React/RCTUIManager.h>
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#import <React/RCTUtils.h>
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#import <React/UIView+React.h>
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#import "RCTInputAccessoryView.h"
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#import "RCTInputAccessoryViewContent.h"
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#import "RCTTextAttributes.h"
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#import "RCTTextSelection.h"
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@implementation RCTBaseTextInputView {
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__weak RCTBridge *_bridge;
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__weak RCTEventDispatcher *_eventDispatcher;
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BOOL _hasInputAccesoryView;
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NSString *_Nullable _predictedText;
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NSInteger _nativeEventCount;
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}
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- (instancetype)initWithBridge:(RCTBridge *)bridge
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{
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RCTAssertParam(bridge);
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if (self = [super initWithFrame:CGRectZero]) {
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_bridge = bridge;
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_eventDispatcher = bridge.eventDispatcher;
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}
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return self;
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}
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RCT_NOT_IMPLEMENTED(- (instancetype)init)
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RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)decoder)
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RCT_NOT_IMPLEMENTED(- (instancetype)initWithFrame:(CGRect)frame)
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- (UIView<RCTBackedTextInputViewProtocol> *)backedTextInputView
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{
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RCTAssert(NO, @"-[RCTBaseTextInputView backedTextInputView] must be implemented in subclass.");
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return nil;
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}
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#pragma mark - RCTComponent
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- (void)didUpdateReactSubviews
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{
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// Do nothing.
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}
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#pragma mark - Properties
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- (void)setTextAttributes:(RCTTextAttributes *)textAttributes
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{
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_textAttributes = textAttributes;
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[self enforceTextAttributesIfNeeded];
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}
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- (void)enforceTextAttributesIfNeeded
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{
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id<RCTBackedTextInputViewProtocol> backedTextInputView = self.backedTextInputView;
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if (backedTextInputView.attributedText.string.length != 0) {
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return;
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}
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backedTextInputView.font = _textAttributes.effectiveFont;
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backedTextInputView.textColor = _textAttributes.effectiveForegroundColor;
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backedTextInputView.textAlignment = _textAttributes.alignment;
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}
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- (void)setReactPaddingInsets:(UIEdgeInsets)reactPaddingInsets
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{
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_reactPaddingInsets = reactPaddingInsets;
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// We apply `paddingInsets` as `backedTextInputView`'s `textContainerInset`.
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self.backedTextInputView.textContainerInset = reactPaddingInsets;
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[self setNeedsLayout];
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}
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- (void)setReactBorderInsets:(UIEdgeInsets)reactBorderInsets
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{
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_reactBorderInsets = reactBorderInsets;
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// We apply `borderInsets` as `backedTextInputView` layout offset.
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self.backedTextInputView.frame = UIEdgeInsetsInsetRect(self.bounds, reactBorderInsets);
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[self setNeedsLayout];
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}
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- (NSAttributedString *)attributedText
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{
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return self.backedTextInputView.attributedText;
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}
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- (BOOL)textOf:(NSAttributedString*)newText equals:(NSAttributedString*)oldText{
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// When the dictation is running we can't update the attibuted text on the backed up text view
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// because setting the attributed string will kill the dictation. This means that we can't impose
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// the settings on a dictation.
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// Similarly, when the user is in the middle of inputting some text in Japanese/Chinese, there will be styling on the
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// text that we should disregard. See https://developer.apple.com/documentation/uikit/uitextinput/1614489-markedtextrange?language=objc
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// for more info.
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// Lastly, when entering a password, etc., there will be additional styling on the field as the native text view
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// handles showing the last character for a split second.
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BOOL shouldFallbackToBareTextComparison =
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[self.backedTextInputView.textInputMode.primaryLanguage isEqualToString:@"dictation"] ||
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self.backedTextInputView.markedTextRange ||
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self.backedTextInputView.isSecureTextEntry;
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if (shouldFallbackToBareTextComparison) {
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return ([newText.string isEqualToString:oldText.string]);
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} else {
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return ([newText isEqualToAttributedString:oldText]);
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}
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}
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- (void)setAttributedText:(NSAttributedString *)attributedText
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{
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NSInteger eventLag = _nativeEventCount - _mostRecentEventCount;
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BOOL textNeedsUpdate = NO;
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// Remove tag attribute to ensure correct attributed string comparison.
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NSMutableAttributedString *const backedTextInputViewTextCopy = [self.backedTextInputView.attributedText mutableCopy];
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NSMutableAttributedString *const attributedTextCopy = [attributedText mutableCopy];
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[backedTextInputViewTextCopy removeAttribute:RCTTextAttributesTagAttributeName
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range:NSMakeRange(0, backedTextInputViewTextCopy.length)];
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[attributedTextCopy removeAttribute:RCTTextAttributesTagAttributeName
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range:NSMakeRange(0, attributedTextCopy.length)];
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textNeedsUpdate = ([self textOf:attributedTextCopy equals:backedTextInputViewTextCopy] == NO);
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if (eventLag == 0 && textNeedsUpdate) {
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UITextRange *selection = self.backedTextInputView.selectedTextRange;
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NSInteger oldTextLength = self.backedTextInputView.attributedText.string.length;
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self.backedTextInputView.attributedText = attributedText;
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if (selection.empty) {
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// Maintaining a cursor position relative to the end of the old text.
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NSInteger offsetStart =
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[self.backedTextInputView offsetFromPosition:self.backedTextInputView.beginningOfDocument
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toPosition:selection.start];
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NSInteger offsetFromEnd = oldTextLength - offsetStart;
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NSInteger newOffset = attributedText.string.length - offsetFromEnd;
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UITextPosition *position =
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[self.backedTextInputView positionFromPosition:self.backedTextInputView.beginningOfDocument
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offset:newOffset];
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[self.backedTextInputView setSelectedTextRange:[self.backedTextInputView textRangeFromPosition:position toPosition:position]
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notifyDelegate:YES];
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}
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[self updateLocalData];
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} else if (eventLag > RCTTextUpdateLagWarningThreshold) {
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RCTLogWarn(@"Native TextInput(%@) is %lld events ahead of JS - try to make your JS faster.", self.backedTextInputView.attributedText.string, (long long)eventLag);
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}
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}
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- (RCTTextSelection *)selection
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{
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id<RCTBackedTextInputViewProtocol> backedTextInputView = self.backedTextInputView;
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UITextRange *selectedTextRange = backedTextInputView.selectedTextRange;
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return [[RCTTextSelection new] initWithStart:[backedTextInputView offsetFromPosition:backedTextInputView.beginningOfDocument toPosition:selectedTextRange.start]
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end:[backedTextInputView offsetFromPosition:backedTextInputView.beginningOfDocument toPosition:selectedTextRange.end]];
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}
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- (void)setSelection:(RCTTextSelection *)selection
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{
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if (!selection) {
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return;
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}
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id<RCTBackedTextInputViewProtocol> backedTextInputView = self.backedTextInputView;
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UITextRange *previousSelectedTextRange = backedTextInputView.selectedTextRange;
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UITextPosition *start = [backedTextInputView positionFromPosition:backedTextInputView.beginningOfDocument offset:selection.start];
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UITextPosition *end = [backedTextInputView positionFromPosition:backedTextInputView.beginningOfDocument offset:selection.end];
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UITextRange *selectedTextRange = [backedTextInputView textRangeFromPosition:start toPosition:end];
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NSInteger eventLag = _nativeEventCount - _mostRecentEventCount;
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if (eventLag == 0 && ![previousSelectedTextRange isEqual:selectedTextRange]) {
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[backedTextInputView setSelectedTextRange:selectedTextRange notifyDelegate:NO];
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} else if (eventLag > RCTTextUpdateLagWarningThreshold) {
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RCTLogWarn(@"Native TextInput(%@) is %lld events ahead of JS - try to make your JS faster.", backedTextInputView.attributedText.string, (long long)eventLag);
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}
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}
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- (void)setTextContentType:(NSString *)type
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{
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#if defined(__IPHONE_OS_VERSION_MAX_ALLOWED) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0
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if (@available(iOS 10.0, *)) {
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// Setting textContentType to an empty string will disable any
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// default behaviour, like the autofill bar for password inputs
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self.backedTextInputView.textContentType = [type isEqualToString:@"none"] ? @"" : type;
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}
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#endif
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}
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- (UIKeyboardType)keyboardType
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{
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return self.backedTextInputView.keyboardType;
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}
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- (void)setKeyboardType:(UIKeyboardType)keyboardType
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{
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UIView<RCTBackedTextInputViewProtocol> *textInputView = self.backedTextInputView;
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if (textInputView.keyboardType != keyboardType) {
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textInputView.keyboardType = keyboardType;
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// Without the call to reloadInputViews, the keyboard will not change until the textview field (the first responder) loses and regains focus.
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if (textInputView.isFirstResponder) {
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[textInputView reloadInputViews];
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}
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}
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}
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#pragma mark - RCTBackedTextInputDelegate
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- (BOOL)textInputShouldBeginEditing
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{
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return YES;
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}
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- (void)textInputDidBeginEditing
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{
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if (_clearTextOnFocus) {
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self.backedTextInputView.attributedText = [NSAttributedString new];
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}
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if (_selectTextOnFocus) {
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[self.backedTextInputView selectAll:nil];
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}
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[_eventDispatcher sendTextEventWithType:RCTTextEventTypeFocus
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reactTag:self.reactTag
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text:self.backedTextInputView.attributedText.string
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key:nil
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eventCount:_nativeEventCount];
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}
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- (BOOL)textInputShouldEndEditing
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{
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return YES;
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}
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- (void)textInputDidEndEditing
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{
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[_eventDispatcher sendTextEventWithType:RCTTextEventTypeEnd
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reactTag:self.reactTag
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text:self.backedTextInputView.attributedText.string
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key:nil
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eventCount:_nativeEventCount];
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[_eventDispatcher sendTextEventWithType:RCTTextEventTypeBlur
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reactTag:self.reactTag
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text:self.backedTextInputView.attributedText.string
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key:nil
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eventCount:_nativeEventCount];
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}
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- (BOOL)textInputShouldReturn
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{
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// We send `submit` event here, in `textInputShouldReturn`
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// (not in `textInputDidReturn)`, because of semantic of the event:
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// `onSubmitEditing` is called when "Submit" button
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// (the blue key on onscreen keyboard) did pressed
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// (no connection to any specific "submitting" process).
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[_eventDispatcher sendTextEventWithType:RCTTextEventTypeSubmit
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reactTag:self.reactTag
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text:self.backedTextInputView.attributedText.string
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key:nil
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eventCount:_nativeEventCount];
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return _blurOnSubmit;
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}
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- (void)textInputDidReturn
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{
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// Does nothing.
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}
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- (BOOL)textInputShouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
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{
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id<RCTBackedTextInputViewProtocol> backedTextInputView = self.backedTextInputView;
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if (!backedTextInputView.textWasPasted) {
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[_eventDispatcher sendTextEventWithType:RCTTextEventTypeKeyPress
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reactTag:self.reactTag
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text:nil
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key:text
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eventCount:_nativeEventCount];
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}
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if (_maxLength) {
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NSUInteger allowedLength = _maxLength.integerValue - backedTextInputView.attributedText.string.length + range.length;
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if (text.length > allowedLength) {
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// If we typed/pasted more than one character, limit the text inputted.
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if (text.length > 1) {
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// Truncate the input string so the result is exactly maxLength
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NSString *limitedString = [text substringToIndex:allowedLength];
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NSMutableAttributedString *newAttributedText = [backedTextInputView.attributedText mutableCopy];
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[newAttributedText replaceCharactersInRange:range withString:limitedString];
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backedTextInputView.attributedText = newAttributedText;
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_predictedText = newAttributedText.string;
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// Collapse selection at end of insert to match normal paste behavior.
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UITextPosition *insertEnd = [backedTextInputView positionFromPosition:backedTextInputView.beginningOfDocument
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offset:(range.location + allowedLength)];
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[backedTextInputView setSelectedTextRange:[backedTextInputView textRangeFromPosition:insertEnd toPosition:insertEnd]
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notifyDelegate:YES];
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[self textInputDidChange];
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}
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return NO;
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}
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}
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if (range.location + range.length > _predictedText.length) {
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// _predictedText got out of sync in a bad way, so let's just force sync it. Haven't been able to repro this, but
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// it's causing a real crash here: #6523822
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_predictedText = backedTextInputView.attributedText.string;
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}
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NSString *previousText = [_predictedText substringWithRange:range] ?: @"";
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// After clearing the text by replacing it with an empty string, `_predictedText`
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// still preserves the deleted text.
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// As the first character in the TextInput always comes with the range value (0, 0),
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// we should check the range value in order to avoid appending a character to the deleted string
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// (which caused the issue #18374)
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if (!NSEqualRanges(range, NSMakeRange(0, 0)) && _predictedText) {
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_predictedText = [_predictedText stringByReplacingCharactersInRange:range withString:text];
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} else {
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_predictedText = text;
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}
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if (_onTextInput) {
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_onTextInput(@{
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@"text": text,
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@"previousText": previousText,
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@"range": @{
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@"start": @(range.location),
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@"end": @(range.location + range.length)
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},
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@"eventCount": @(_nativeEventCount),
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});
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}
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return YES;
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}
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- (void)textInputDidChange
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{
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[self updateLocalData];
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id<RCTBackedTextInputViewProtocol> backedTextInputView = self.backedTextInputView;
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// Detect when `backedTextInputView` updates happend that didn't invoke `shouldChangeTextInRange`
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// (e.g. typing simplified chinese in pinyin will insert and remove spaces without
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// calling shouldChangeTextInRange). This will cause JS to get out of sync so we
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// update the mismatched range.
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NSRange currentRange;
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NSRange predictionRange;
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if (findMismatch(backedTextInputView.attributedText.string, _predictedText, ¤tRange, &predictionRange)) {
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NSString *replacement = [backedTextInputView.attributedText.string substringWithRange:currentRange];
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[self textInputShouldChangeTextInRange:predictionRange replacementText:replacement];
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// JS will assume the selection changed based on the location of our shouldChangeTextInRange, so reset it.
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[self textInputDidChangeSelection];
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_predictedText = backedTextInputView.attributedText.string;
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}
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_nativeEventCount++;
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if (_onChange) {
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_onChange(@{
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@"text": self.attributedText.string,
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@"target": self.reactTag,
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@"eventCount": @(_nativeEventCount),
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});
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}
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}
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- (void)textInputDidChangeSelection
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{
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if (!_onSelectionChange) {
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return;
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}
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RCTTextSelection *selection = self.selection;
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_onSelectionChange(@{
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@"selection": @{
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@"start": @(selection.start),
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@"end": @(selection.end),
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},
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});
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}
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- (void)updateLocalData
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{
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[self enforceTextAttributesIfNeeded];
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[_bridge.uiManager setLocalData:[self.backedTextInputView.attributedText copy]
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forView:self];
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}
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#pragma mark - Layout (in UIKit terms, with all insets)
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- (CGSize)intrinsicContentSize
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{
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CGSize size = self.backedTextInputView.intrinsicContentSize;
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size.width += _reactBorderInsets.left + _reactBorderInsets.right;
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size.height += _reactBorderInsets.top + _reactBorderInsets.bottom;
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// Returning value DOES include border and padding insets.
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return size;
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}
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- (CGSize)sizeThatFits:(CGSize)size
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{
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CGFloat compoundHorizontalBorderInset = _reactBorderInsets.left + _reactBorderInsets.right;
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CGFloat compoundVerticalBorderInset = _reactBorderInsets.top + _reactBorderInsets.bottom;
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size.width -= compoundHorizontalBorderInset;
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size.height -= compoundVerticalBorderInset;
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// Note: `paddingInsets` was already included in `backedTextInputView` size
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// because it was applied as `textContainerInset`.
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CGSize fittingSize = [self.backedTextInputView sizeThatFits:size];
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fittingSize.width += compoundHorizontalBorderInset;
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fittingSize.height += compoundVerticalBorderInset;
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// Returning value DOES include border and padding insets.
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return fittingSize;
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}
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#pragma mark - Accessibility
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- (UIView *)reactAccessibilityElement
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{
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return self.backedTextInputView;
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}
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#pragma mark - Focus Control
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- (void)reactFocus
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{
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[self.backedTextInputView reactFocus];
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}
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- (void)reactBlur
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{
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[self.backedTextInputView reactBlur];
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}
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- (void)didMoveToWindow
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{
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[self.backedTextInputView reactFocusIfNeeded];
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}
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#pragma mark - Custom Input Accessory View
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- (void)didSetProps:(NSArray<NSString *> *)changedProps
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{
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if ([changedProps containsObject:@"inputAccessoryViewID"] && self.inputAccessoryViewID) {
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[self setCustomInputAccessoryViewWithNativeID:self.inputAccessoryViewID];
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} else if (!self.inputAccessoryViewID) {
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[self setDefaultInputAccessoryView];
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}
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}
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- (void)setCustomInputAccessoryViewWithNativeID:(NSString *)nativeID
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{
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#if !TARGET_OS_TV
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__weak RCTBaseTextInputView *weakSelf = self;
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[_bridge.uiManager rootViewForReactTag:self.reactTag withCompletion:^(UIView *rootView) {
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RCTBaseTextInputView *strongSelf = weakSelf;
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if (rootView) {
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UIView *accessoryView = [strongSelf->_bridge.uiManager viewForNativeID:nativeID
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withRootTag:rootView.reactTag];
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if (accessoryView && [accessoryView isKindOfClass:[RCTInputAccessoryView class]]) {
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strongSelf.backedTextInputView.inputAccessoryView = ((RCTInputAccessoryView *)accessoryView).inputAccessoryView;
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[strongSelf reloadInputViewsIfNecessary];
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}
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}
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}];
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#endif /* !TARGET_OS_TV */
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}
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- (void)setDefaultInputAccessoryView
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{
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#if !TARGET_OS_TV
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UIView<RCTBackedTextInputViewProtocol> *textInputView = self.backedTextInputView;
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UIKeyboardType keyboardType = textInputView.keyboardType;
|
|
|
|
// These keyboard types (all are number pads) don't have a "Done" button by default,
|
|
// so we create an `inputAccessoryView` with this button for them.
|
|
BOOL shouldHaveInputAccesoryView =
|
|
(
|
|
keyboardType == UIKeyboardTypeNumberPad ||
|
|
keyboardType == UIKeyboardTypePhonePad ||
|
|
keyboardType == UIKeyboardTypeDecimalPad ||
|
|
keyboardType == UIKeyboardTypeASCIICapableNumberPad
|
|
) &&
|
|
textInputView.returnKeyType == UIReturnKeyDone;
|
|
|
|
if (_hasInputAccesoryView == shouldHaveInputAccesoryView) {
|
|
return;
|
|
}
|
|
|
|
_hasInputAccesoryView = shouldHaveInputAccesoryView;
|
|
|
|
if (shouldHaveInputAccesoryView) {
|
|
UIToolbar *toolbarView = [[UIToolbar alloc] init];
|
|
[toolbarView sizeToFit];
|
|
UIBarButtonItem *flexibleSpace =
|
|
[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
|
|
target:nil
|
|
action:nil];
|
|
UIBarButtonItem *doneButton =
|
|
[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone
|
|
target:self
|
|
action:@selector(handleInputAccessoryDoneButton)];
|
|
toolbarView.items = @[flexibleSpace, doneButton];
|
|
textInputView.inputAccessoryView = toolbarView;
|
|
}
|
|
else {
|
|
textInputView.inputAccessoryView = nil;
|
|
}
|
|
[self reloadInputViewsIfNecessary];
|
|
#endif /* !TARGET_OS_TV */
|
|
}
|
|
|
|
- (void)reloadInputViewsIfNecessary
|
|
{
|
|
// We have to call `reloadInputViews` for focused text inputs to update an accessory view.
|
|
if (self.backedTextInputView.isFirstResponder) {
|
|
[self.backedTextInputView reloadInputViews];
|
|
}
|
|
}
|
|
|
|
- (void)handleInputAccessoryDoneButton
|
|
{
|
|
if ([self textInputShouldReturn]) {
|
|
[self.backedTextInputView endEditing:YES];
|
|
}
|
|
}
|
|
|
|
#pragma mark - Helpers
|
|
|
|
static BOOL findMismatch(NSString *first, NSString *second, NSRange *firstRange, NSRange *secondRange)
|
|
{
|
|
NSInteger firstMismatch = -1;
|
|
for (NSUInteger ii = 0; ii < MAX(first.length, second.length); ii++) {
|
|
if (ii >= first.length || ii >= second.length || [first characterAtIndex:ii] != [second characterAtIndex:ii]) {
|
|
firstMismatch = ii;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (firstMismatch == -1) {
|
|
return NO;
|
|
}
|
|
|
|
NSUInteger ii = second.length;
|
|
NSUInteger lastMismatch = first.length;
|
|
while (ii > firstMismatch && lastMismatch > firstMismatch) {
|
|
if ([first characterAtIndex:(lastMismatch - 1)] != [second characterAtIndex:(ii - 1)]) {
|
|
break;
|
|
}
|
|
ii--;
|
|
lastMismatch--;
|
|
}
|
|
|
|
*firstRange = NSMakeRange(firstMismatch, lastMismatch - firstMismatch);
|
|
*secondRange = NSMakeRange(firstMismatch, ii - firstMismatch);
|
|
return YES;
|
|
}
|
|
|
|
@end
|