support for round buttons

src/declarativeimports/plasmacomponents/qml/styles/ToolButtonStyle.qml

@@ -102,8 +102,66 @@ QtQuickControlStyle.ButtonStyle {
         }
     }
 
-    background: Item {
+    background: {
+        if (control.text.length == 0 && control.width == control.height && (control.parent && control.parent.checkedButton === undefined) && !control.flat) {
+            return roundButtonComponent
+        } else {
+            return buttonComponent
+        }
+    }
 
+    Component {
+        id: roundButtonComponent
+        Item {
+            id: roundButtonDelegate
+            anchors.fill: parent
+            property QtObject margins: QtObject {
+                property int left: delegate.width/8
+                property int top: delegate.width/8
+                property int right: delegate.width/8
+                property int bottom: delegate.width/8
+            }
+            property alias hasOverState: roundShadow.hasOverState
+            Private.RoundShadow {
+                id: roundShadow
+                visible: !flat
+                anchors.fill: parent
+                state: {
+                    if (control.pressed) {
+                        return "hidden"
+                    } else if (control.hovered) {
+                        return "hover"
+                    } else if (control.activeFocus) {
+                        return "focus"
+                    } else {
+                        return "shadow"
+                    }
+                }
+            }
+
+            PlasmaCore.Svg {
+                id: buttonSvg
+                imagePath: "widgets/actionbutton"
+            }
+
+            PlasmaCore.SvgItem {
+                id: buttonItem
+                svg: buttonSvg
+                elementId: (control.pressed || control.checked) ? "pressed" : "normal"
+                width: Math.floor(parent.height/2) * 2
+                height: width
+                //internal: if there is no hover status, don't paint on mouse over in touchscreens
+                opacity: (control.pressed || control.checked || !control.flat || (roundShadow.hasOverState && mouse.containsMouse)) ? 1 : 0
+                Behavior on opacity {
+                    PropertyAnimation { duration: units.longDuration }
+                }
+            }
+        }
+    }
+
+    Component {
+        id: buttonComponent
+        Item {
             implicitHeight: Math.floor(Math.max(theme.mSize(theme.defaultFont).height*1.6, style.minimumHeight))
 
             implicitWidth: {
@@ -199,4 +257,5 @@ QtQuickControlStyle.ButtonStyle {
                 padding.bottom = surfaceNormal.margins.bottom
             }
         }
+    }
 }