android 代码控制LinearLayout 宽度高度 报错widget.LinearLayout$LayoutParams cannot be cast to android.widget...

错误：代码修改LinearLayout宽度时，报错java.lang.ClassCastException: android.widget.LinearLayoutLayoutParams cannot be cast to android.widget.RelativeLayoutLayoutParams
布局：LinearLayout父布局是RelativeLayout
因此，在代码里修改LinearLayout宽度时不需要new，需要获取它自己的LayoutParams

 ViewGroup.LayoutParams params = LinearLayout.getLayoutParams();
                    params.height = ViewGroup.LayoutParams.MATCH_PARENT;
                    LinearLayout.setLayoutParams(params);