Maybe try modifying the component itself by adding a maximum line count like below, need to save this as a .qml file (eg: PageHeaderCustom) then change PageHeader to PageHeaderCustom (untested I have no device near me ):
/****************************************************************************************
**
** Copyright (C) 2013 Jolla Ltd.
** Contact: Joona Petrell <joona.petrell@jollamobile.com>
** All rights reserved.
**
** This file is part of Sailfish Silica UI component package.
**
** You may use this file under the terms of BSD license as follows:
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** * Neither the name of the Jolla Ltd nor the
** names of its contributors may be used to endorse or promote products
** derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
** WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
** DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR
** ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
** (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
** ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
** SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**
****************************************************************************************/
import QtQuick 2.6
import Sailfish.Silica 1.0
import "private/Util.js" as Util
SilicaControl {
id: pageHeader
property alias title: headerText.text
property alias _titleItem: headerText
property alias wrapMode: headerText.wrapMode
property alias extraContent: extraContentPlaceholder
property string description
property int descriptionWrapMode: Text.NoWrap
property Item page
property alias titleColor: headerText.color
property real leftMargin: Theme.horizontalPageMargin
property real rightMargin: Theme.horizontalPageMargin
property real descriptionRightMargin: rightMargin
property bool interactive: enabled && page && page.canNavigateForward
readonly property bool defaultHighlighted: interactive
&& ((_navigateForwardMouseArea && _navigateForwardMouseArea.containsMouse)
|| (pageStack._pageStackIndicator && pageStack._pageStackIndicator.forwardIndicatorDown))
property Item _descriptionLabel
property real _preferredHeight: page && page.isLandscape ? Theme.itemSizeSmall : Theme.itemSizeLarge
onDescriptionChanged: {
if (description.length > 0 && !_descriptionLabel) {
var component = Qt.createComponent(Qt.resolvedUrl("private/PageHeaderDescription.qml"))
if (component.status === Component.Ready) {
_descriptionLabel = component.createObject(pageHeader,
{ "wrapMode": Qt.binding(function() { return pageHeader.descriptionWrapMode }) })
} else {
console.warn("PageHeaderDescription.qml instantiation failed " + component.errorString())
}
}
}
property Item _navigateForwardMouseArea
onInteractiveChanged: {
if (interactive && !_navigateForwardMouseArea) {
var component = Qt.createComponent(Qt.resolvedUrl("private/PageHeaderMouseArea.qml"))
if (component.status === Component.Ready) {
_navigateForwardMouseArea = component.createObject(pageHeader)
} else {
console.warn("PageHeaderMouseArea.qml instantiation failed " + component.errorString())
}
}
}
Component.onCompleted: {
if (!page) {
page = Util.findPage(pageHeader)
}
}
width: parent ? parent.width : Screen.width
// set height that keeps the first line of text aligned with the page indicator
height: Math.max(_preferredHeight, headerText.y + headerText.height + ((_descriptionLabel && description.length > 0) ? _descriptionLabel.height : 0) + Theme.paddingMedium)
highlighted: defaultHighlighted
Label {
id: headerText
// Don't allow the label to extend over the page stack indicator
maximumLineCount: 1
width: Math.min(implicitWidth, parent.width - leftMargin - rightMargin)
truncationMode: TruncationMode.Fade
// color should indicate if interactive
color: interactive
? (highlighted ? palette.highlightColor : palette.primaryColor)
: (highlighted ? palette.primaryColor : palette.highlightColor)
// align first line with page indicator
y: Math.floor(_preferredHeight/2 - metrics.height/2)
anchors {
right: parent.right
rightMargin: pageHeader.rightMargin
}
font {
pixelSize: Theme.fontSizeLarge
family: Theme.fontFamilyHeading
}
TextMetrics {
id: metrics
font: headerText.font
text: "X"
}
}
Item {
id: extraContentPlaceholder
// Extend extraContent to the full area to the left of the title.
anchors {
left: parent.left
leftMargin: pageHeader.leftMargin
right: headerText.left
top: parent.top
bottom: parent.bottom
}
}
}
Or before the actual someTitleFromVariable string is set perform a length check and if it exceeds lets say 50 then use something like .substring JS function to trim the string (https://www.w3schools.com/jsref/jsref_substring.asp)
