harbour-fernschreiber/qml/components/MultilineEmojiLabel.qml
Slava Monich d2d6fac778 Fixed Emoji image positioning in multiline StyledText
Combination of maximumLineCount and TruncationMode.Elide (or Fade)
breaks Emoji image alignment, pushing the image down. Explicitly
truncating the text fixes the problem, at expense of certain runtime
overhead.

Also, toggle full and truncated Web page preview on tap.
2020-12-24 05:45:27 +02:00

78 lines
2.7 KiB
QML

/*
Copyright (C) 2020 Slava Monich and other contributors
This file is part of Fernschreiber.
Fernschreiber is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Fernschreiber is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Fernschreiber. If not, see <http://www.gnu.org/licenses/>.
*/
import QtQuick 2.0
import Sailfish.Silica 1.0
import "../js/twemoji.js" as Emoji
// Combination of maximumLineCount and TruncationMode.Elide (or Fade) breaks
// Emoji image alignment, pushing the image down. This one aligns the image
// correctly on its line.
Label {
property string rawText
property int maxLineCount
wrapMode: Text.Wrap
textFormat: Text.StyledText
truncationMode: TruncationMode.Elide
// lineCount is unreliable for StyledText with images and line breaks
readonly property int fontSize: font.pixelSize
readonly property int actualLineHeight: (text === rawText) ? fontSize : (fontSize * 6 / 5)
readonly property int actualLineCount: Math.floor(implicitHeight/actualLineHeight)
Component.onCompleted: refitText()
onFontSizeChanged: refitText()
onWidthChanged: refitText()
onRawTextChanged: refitText()
onMaxLineCountChanged: refitText()
function emojify(str) {
return Emoji.emojify(str, fontSize)
}
function refitText() {
text = emojify(rawText)
if (maxLineCount > 0) {
var divisor = 1
var max = rawText.length
var min = max
while (actualLineCount > maxLineCount && divisor < rawText.length) {
max = min
divisor++
min = rawText.length/divisor
text = emojify(rawText.substr(0, min) + "…")
}
while (min < max) {
var mid = Math.floor((min + max)/2)
if (mid === min) {
text = emojify(rawText.substr(0, min) + "…")
break
} else {
text = emojify(rawText.substr(0, mid) + "…")
if (actualLineCount > maxLineCount) {
max = mid
} else {
min = mid
}
}
}
}
}
}