java - Strange title corruption of activity when using ListView -

i've got class (let's call mywidget now) extends view in custom drawing in ondraw(). mywidget works fine in situations, except when either adding mywidget listview or scrollview within tabview. when in 1 of these configurations, consistently observe scrolling overwrite title area of view partial image of contents of 1 of instances of mywidget.

i know confusing description of problem here's screenshot of corruption:

screen corruption

any ideas?!

addition: clipping logic use:

try {         canvas.save(canvas.all_save_flag);         // clipping here     } {         canvas.restore(); } 

it looks view's custom drawing code doing tricks clip rect , not saving/restoring canvas state.