react-native/Libraries/Text/RCTTextField.m

351 lines
12 KiB
Objective-C

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
#import "RCTTextField.h"
#import <React/RCTConvert.h>
#import <React/RCTEventDispatcher.h>
#import <React/RCTUtils.h>
#import <React/UIView+React.h>
#import "RCTTextSelection.h"
@interface RCTTextField()
- (BOOL)shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string;
- (BOOL)keyboardInputShouldDelete;
- (BOOL)textFieldShouldEndEditing;
@end
@interface RCTTextFieldDelegateProxy: NSObject <UITextFieldDelegate>
@end
@implementation RCTTextFieldDelegateProxy
- (BOOL)textField:(RCTTextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
return [textField shouldChangeCharactersInRange:range replacementString:string];
}
- (BOOL)keyboardInputShouldDelete:(RCTTextField *)textField
{
return [textField keyboardInputShouldDelete];
}
- (BOOL)textFieldShouldEndEditing:(RCTTextField *)textField {
return [textField textFieldShouldEndEditing];
}
@end
@implementation RCTTextField
{
RCTEventDispatcher *_eventDispatcher;
NSInteger _nativeEventCount;
BOOL _submitted;
UITextRange *_previousSelectionRange;
BOOL _textWasPasted;
NSString *_finalText;
RCTTextFieldDelegateProxy *_delegateProxy;
}
- (instancetype)initWithEventDispatcher:(RCTEventDispatcher *)eventDispatcher
{
if ((self = [super initWithFrame:CGRectZero])) {
RCTAssert(eventDispatcher, @"eventDispatcher is a required parameter");
_eventDispatcher = eventDispatcher;
[self addTarget:self action:@selector(textFieldDidChange) forControlEvents:UIControlEventEditingChanged];
[self addTarget:self action:@selector(textFieldBeginEditing) forControlEvents:UIControlEventEditingDidBegin];
[self addTarget:self action:@selector(textFieldEndEditing) forControlEvents:UIControlEventEditingDidEnd];
[self addTarget:self action:@selector(textFieldSubmitEditing) forControlEvents:UIControlEventEditingDidEndOnExit];
[self addObserver:self forKeyPath:@"selectedTextRange" options:0 context:nil];
_blurOnSubmit = YES;
// We cannot use `self.delegate = self;` here because `UITextField` implements some of these delegate methods itself,
// so if we implement this delegate on self, we will override some of its behaviours.
_delegateProxy = [RCTTextFieldDelegateProxy new];
self.delegate = _delegateProxy;
}
return self;
}
- (void)dealloc
{
[self removeObserver:self forKeyPath:@"selectedTextRange"];
}
RCT_NOT_IMPLEMENTED(- (instancetype)initWithFrame:(CGRect)frame)
RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)
- (void)sendKeyValueForString:(NSString *)string
{
[_eventDispatcher sendTextEventWithType:RCTTextEventTypeKeyPress
reactTag:self.reactTag
text:nil
key:string
eventCount:_nativeEventCount];
}
// This method is overridden for `onKeyPress`. The manager
// will not send a keyPress for text that was pasted.
- (void)paste:(id)sender
{
_textWasPasted = YES;
[super paste:sender];
}
- (void)setSelection:(RCTTextSelection *)selection
{
if (!selection) {
return;
}
UITextRange *currentSelection = self.selectedTextRange;
UITextPosition *start = [self positionFromPosition:self.beginningOfDocument offset:selection.start];
UITextPosition *end = [self positionFromPosition:self.beginningOfDocument offset:selection.end];
UITextRange *selectedTextRange = [self textRangeFromPosition:start toPosition:end];
NSInteger eventLag = _nativeEventCount - _mostRecentEventCount;
if (eventLag == 0 && ![currentSelection isEqual:selectedTextRange]) {
_previousSelectionRange = selectedTextRange;
self.selectedTextRange = selectedTextRange;
} else if (eventLag > RCTTextUpdateLagWarningThreshold) {
RCTLogWarn(@"Native TextInput(%@) is %zd events ahead of JS - try to make your JS faster.", self.text, eventLag);
}
}
- (void)setText:(NSString *)text
{
NSInteger eventLag = _nativeEventCount - _mostRecentEventCount;
if (eventLag == 0 && ![text isEqualToString:self.text]) {
UITextRange *selection = self.selectedTextRange;
NSInteger oldTextLength = self.text.length;
super.text = text;
if (selection.empty) {
// maintain cursor position relative to the end of the old text
NSInteger offsetStart = [self offsetFromPosition:self.beginningOfDocument toPosition:selection.start];
NSInteger offsetFromEnd = oldTextLength - offsetStart;
NSInteger newOffset = text.length - offsetFromEnd;
UITextPosition *position = [self positionFromPosition:self.beginningOfDocument offset:newOffset];
self.selectedTextRange = [self textRangeFromPosition:position toPosition:position];
}
} else if (eventLag > RCTTextUpdateLagWarningThreshold) {
RCTLogWarn(@"Native TextInput(%@) is %zd events ahead of JS - try to make your JS faster.", self.text, eventLag);
}
}
static void RCTUpdatePlaceholder(RCTTextField *self)
{
if (self.placeholder.length > 0 && self.placeholderTextColor) {
self.attributedPlaceholder = [[NSAttributedString alloc] initWithString:self.placeholder
attributes:@{
NSForegroundColorAttributeName : self.placeholderTextColor
}];
} else if (self.placeholder.length) {
self.attributedPlaceholder = [[NSAttributedString alloc] initWithString:self.placeholder];
}
}
- (void)setPlaceholderTextColor:(UIColor *)placeholderTextColor
{
_placeholderTextColor = placeholderTextColor;
RCTUpdatePlaceholder(self);
}
- (void)setPlaceholder:(NSString *)placeholder
{
super.placeholder = placeholder;
RCTUpdatePlaceholder(self);
}
- (CGRect)caretRectForPosition:(UITextPosition *)position
{
if (_caretHidden) {
return CGRectZero;
}
return [super caretRectForPosition:position];
}
- (CGRect)textRectForBounds:(CGRect)bounds
{
CGRect rect = [super textRectForBounds:bounds];
return UIEdgeInsetsInsetRect(rect, _contentInset);
}
- (CGRect)editingRectForBounds:(CGRect)bounds
{
return [self textRectForBounds:bounds];
}
- (void)textFieldDidChange
{
_nativeEventCount++;
[_eventDispatcher sendTextEventWithType:RCTTextEventTypeChange
reactTag:self.reactTag
text:self.text
key:nil
eventCount:_nativeEventCount];
// selectedTextRange observer isn't triggered when you type even though the
// cursor position moves, so we send event again here.
[self sendSelectionEvent];
}
- (void)textFieldEndEditing
{
if (![_finalText isEqualToString:self.text]) {
_finalText = nil;
// iOS does't send event `UIControlEventEditingChanged` if the change was happened because of autocorrection
// which was triggered by loosing focus. We assume that if `text` was changed in the middle of loosing focus process,
// we did not receive that event. So, we call `textFieldDidChange` manually.
[self textFieldDidChange];
}
[_eventDispatcher sendTextEventWithType:RCTTextEventTypeEnd
reactTag:self.reactTag
text:self.text
key:nil
eventCount:_nativeEventCount];
}
- (void)textFieldSubmitEditing
{
_submitted = YES;
[_eventDispatcher sendTextEventWithType:RCTTextEventTypeSubmit
reactTag:self.reactTag
text:self.text
key:nil
eventCount:_nativeEventCount];
}
- (void)textFieldBeginEditing
{
[_eventDispatcher sendTextEventWithType:RCTTextEventTypeFocus
reactTag:self.reactTag
text:self.text
key:nil
eventCount:_nativeEventCount];
dispatch_async(dispatch_get_main_queue(), ^{
if (self->_selectTextOnFocus) {
[self selectAll:nil];
}
[self sendSelectionEvent];
});
}
- (void)observeValueForKeyPath:(NSString *)keyPath
ofObject:(RCTTextField *)textField
change:(NSDictionary *)change
context:(void *)context
{
if ([keyPath isEqualToString:@"selectedTextRange"]) {
[self sendSelectionEvent];
}
}
- (void)sendSelectionEvent
{
if (_onSelectionChange &&
self.selectedTextRange != _previousSelectionRange &&
![self.selectedTextRange isEqual:_previousSelectionRange]) {
_previousSelectionRange = self.selectedTextRange;
UITextRange *selection = self.selectedTextRange;
NSInteger start = [self offsetFromPosition:[self beginningOfDocument] toPosition:selection.start];
NSInteger end = [self offsetFromPosition:[self beginningOfDocument] toPosition:selection.end];
_onSelectionChange(@{
@"selection": @{
@"start": @(start),
@"end": @(end),
},
});
}
}
- (BOOL)resignFirstResponder
{
BOOL result = [super resignFirstResponder];
if (result)
{
[_eventDispatcher sendTextEventWithType:RCTTextEventTypeBlur
reactTag:self.reactTag
text:self.text
key:nil
eventCount:_nativeEventCount];
}
return result;
}
- (void)didMoveToWindow
{
[self reactFocusIfNeeded];
}
#pragma mark - UITextFieldDelegate (Proxied)
- (BOOL)shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
// Only allow single keypresses for `onKeyPress`, pasted text will not be sent.
if (_textWasPasted) {
_textWasPasted = NO;
} else {
[self sendKeyValueForString:string];
}
if (_maxLength != nil && ![string isEqualToString:@"\n"]) { // Make sure forms can be submitted via return.
NSUInteger allowedLength = _maxLength.integerValue - MIN(_maxLength.integerValue, self.text.length) + range.length;
if (string.length > allowedLength) {
if (string.length > 1) {
// Truncate the input string so the result is exactly `maxLength`.
NSString *limitedString = [string substringToIndex:allowedLength];
NSMutableString *newString = self.text.mutableCopy;
[newString replaceCharactersInRange:range withString:limitedString];
self.text = newString;
// Collapse selection at end of insert to match normal paste behavior.
UITextPosition *insertEnd = [self positionFromPosition:self.beginningOfDocument
offset:(range.location + allowedLength)];
self.selectedTextRange = [self textRangeFromPosition:insertEnd toPosition:insertEnd];
[self textFieldDidChange];
}
return NO;
}
}
return YES;
}
// This method allows us to detect a `Backspace` keyPress
// even when there is no more text in the TextField.
- (BOOL)keyboardInputShouldDelete
{
[self shouldChangeCharactersInRange:NSMakeRange(0, 0) replacementString:@""];
return YES;
}
- (BOOL)textFieldShouldEndEditing
{
_finalText = self.text;
if (_submitted) {
_submitted = NO;
return _blurOnSubmit;
}
return YES;
}
@end