java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams cannot be cast to android.wid

java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams cannot be cast to android.widget.FrameLayout$LayoutParams

// xml文件

			<FrameLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content">

              ......
			  
                <ImageView
                    android:id="@+id/iv_settings"
                    android:onClick="startSetting"
                    android:layout_margin="10sp"
                    android:layout_gravity="bottom"
                    android:src="@drawable/home_larger_settings"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" />
					
              ......
			  
            </FrameLayout>



  		ImageView mIvSettings = (ImageView) findViewById(R.id.iv_settings);

// 代码块
        LinearLayout.LayoutParams  params =
                new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
//        FrameLayout mFl = (FrameLayout) mIvSettings.getParent();

        params.gravity = Gravity.CENTER;
        mIvSettings.setLayoutParams(params);

原因：因为mIvSettings的是包含在FrameLayout中的，如果要代码设置ImageView的属性的时候一定要new 对类型，比如此处一定要传FrameLayout.LayoutParams ，不然就会报上述错误