转自http://igoesolutions.com/blog/2011/06/20/custom-view-is-not-using-the-2-or-3-argument-view-constructors-xml-attributes-will-not-work/
写三个构造函数就OK了：
public class ExtendedClass extends Button {
public
ExtendedClass(Context context) {
super( context, attrs );
}
public
ExtendedClass(Context context, AttributeSet attrs) {
super( context, attrs );
}
public
ExtendedClass(Context context, AttributeSet attrs, int defStyle) {
super( context, attrs, defStyle );
}
}
转载于:https://www.cnblogs.com/wuyihong/archive/2012/08/18/2645892.html
