c# - Changing the color of the elements of a UserControl -

i have problem whit usercontrol. when try hover change color of components , function "changecolor" isn't fire correctly.

if hover on label or picturebox of usercontrol, evoked event mouseleave

this usercontrol

public partial class infouser : usercontrol {     public infouser()     {         initializecomponent();     }      public void setnome(string nome)     {         labeluserlogged.text = nome;     }      public void changecolor(system.drawing.color color)     {         labeluserlogged.backcolor = color;         pictureboxuser.backcolor = color;     }      private void infouser_mousehover(object sender, eventargs e)     {         changecolor(color.cadetblue);     }      private void infouser_mouseleave(object sender, eventargs e)     {         changecolor(color.whitesmoke);     }  } 

code of designer

 private void initializecomponent()     {         this.labeluserlogged = new system.windows.forms.label();         this.pictureboxuser = new system.windows.forms.picturebox();         ((system.componentmodel.isupportinitialize)(this.pictureboxuser)).begininit();         this.suspendlayout();         //          // labeluserlogged         //          this.labeluserlogged.backcolor = system.drawing.systemcolors.control;         this.labeluserlogged.borderstyle = system.windows.forms.borderstyle.fixedsingle;         this.labeluserlogged.cursor = system.windows.forms.cursors.hand;         this.labeluserlogged.location = new system.drawing.point(0, 0);         this.labeluserlogged.name = "labeluserlogged";         this.labeluserlogged.size = new system.drawing.size(167, 27);         this.labeluserlogged.tabindex = 3;         this.labeluserlogged.text = "non loggato";         this.labeluserlogged.textalign = system.drawing.contentalignment.middlecenter;         //          // pictureboxuser         //          this.pictureboxuser.backcolor = system.drawing.color.transparent;         this.pictureboxuser.cursor = system.windows.forms.cursors.hand;         this.pictureboxuser.image = global::castor.gestionale.properties.resources.user_icon;         this.pictureboxuser.location = new system.drawing.point(5, 6);         this.pictureboxuser.name = "pictureboxuser";         this.pictureboxuser.size = new system.drawing.size(18, 15);         this.pictureboxuser.sizemode = system.windows.forms.pictureboxsizemode.centerimage;         this.pictureboxuser.tabindex = 4;         this.pictureboxuser.tabstop = false;         //          // infouser         //          this.autoscaledimensions = new system.drawing.sizef(6f, 13f);         this.autoscalemode = system.windows.forms.autoscalemode.font;         this.controls.add(this.pictureboxuser);         this.controls.add(this.labeluserlogged);         this.name = "infouser";         this.size = new system.drawing.size(171, 30);         this.mouseleave += new system.eventhandler(this.infouser_mouseleave);         this.mousehover += new system.eventhandler(this.infouser_mousehover);         ((system.componentmodel.isupportinitialize)(this.pictureboxuser)).endinit();         this.resumelayout(false);      } 

child controls of usercontrol receive mouse-input when cursor within it's bounds. so, when mouse "enter" label/picturebox "leave" usercontrol , etc.
make specific child control "transparent" mouse events can use following trick:

const int wm_nchittest = 0x84, httransparent = (-1); class hittesttransparentpicturebox : picturebox {     protected override void wndproc(ref message m) {         if(m.msg == wm_nchittest) {             m.result = new intptr(httransparent);             return;         }         base.wndproc(ref m);     } } class hittesttransparentlabel : label {     protected override void wndproc(ref message m) {         if(m.msg == wm_nchittest) {             m.result = new intptr(httransparent);             return;         }         base.wndproc(ref m);     } } 

then can replace specific controls in usercontrol "mouse-transparent" analogs:

this.labeluserlogged = new hittesttransparentlabel(); this.pictureboxuser = new hittesttransparentpicturebox(); 

after can use following approach create hover-effect on usercontrol:

public infouser() {     initializecomponent();     mouseenter += infouser_mouseenter;     mouseleave += infouser_mouseleave; } void infouser_mouseleave(object sender, eventargs e) {     hover = false; } void infouser_mouseenter(object sender, eventargs e) {     hover = true;    } bool hovercore; protected bool hover {     { return hovercore; }     set {         if(hovercore == value) return;         hovercore = value;         onhoverchanged();     } } void onhoverchanged() {     changecolor(hover ? color.cadetblue : color.whitesmoke); }