I have a hard time understanding the layout tutorial. I am not able to align columns on different rows. For example, what does 3dip mean in android:padding=\"3dip\". The documentation says \"Available
目录1.横向合并1.1concatenate方法1.2hstack方法1.3column_stack方法2.纵向合并2.1concatenate方法2.2vstack方法2.3row_st...