42 lines
1.6 KiB
Swift
42 lines
1.6 KiB
Swift
//
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// Copyright (c) 2020 Open Whisper Systems. All rights reserved.
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//
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import Foundation
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import UIKit
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class AttachmentTextView: MentionTextView {
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private var textIsChanging = false
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override func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
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textIsChanging = true
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return super.textView(self, shouldChangeTextIn: range, replacementText: text)
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}
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override func textViewDidChange(_ textView: UITextView) {
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super.textViewDidChange(textView)
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textIsChanging = false
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}
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override func setContentOffset(_ contentOffset: CGPoint, animated: Bool) {
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// When creating new lines, contentOffset is animated, but because because
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// we are simultaneously resizing the text view, on pre-iOS 13 this can
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// cause the text in the textview to be "too high" in the text view.
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// Solution is to disable animation for setting content offset between
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// -textViewShouldChange... and -textViewDidChange.
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//
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// We can't unilaterally disable *all* animated scrolling because that breaks
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// manipulation of the cursor in scrollable text. Animation is required to
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// slow the text view scrolling down to human scale when the cursor reaches
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// the top or bottom edge.
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let shouldAnimate: Bool
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if #available(iOS 13, *) {
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shouldAnimate = animated
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} else {
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shouldAnimate = animated && !textIsChanging
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}
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super.setContentOffset(contentOffset, animated: shouldAnimate)
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}
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}
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