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How to make QML ListView align bottom-to-top

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Normally QML ListView aligns all items at the top. New items get stacked on bottom. For some use cases like a conversations view you may want a different layout which starts at the bottom and also adds new items there.

The solution

The solution is easier than most people think. Rotation is the keyword.

  • Rotate the ListView by 180°
  • Also rotate the Delegate by 180° to get it back to normal direction. Don't forget to give the delegate the whole width of ListView.view.width! Otherwise your items are right-aligned.
  • In order to get the newest items at the bottom, always insert the newest one at index 0 instead of appending it.

The test code

import QtQuick 1.0

Rectangle {

   width: 300
   height: 300
   
   Rectangle {
       id: button
       color: "red"
       height: 20
       anchors {
           top: parent.top
           left: parent.left
           right: parent.right
       }
        
       Text {
           anchors.centerIn: parent
           text: "Click me to add rows"
       }
       MouseArea {
           anchors.fill: parent
           onClicked: {
               var row = { "id":listModel.count }
               listModel.insert(0, row)
           }
       }
   }
   ListView {
       rotation: 180
       anchors {
           top: button.bottom
           bottom: parent.bottom
           left: parent.left
           right: parent.right
       }
       model: ListModel {
           id: listModel
       }
       delegate: Rectangle {
           rotation: 180
           width: ListView.view.width
           height: 20
           color: "green"
           Text {
               anchors.centerIn: parent
               text: model.id
           }
       }
   }

}