The teacher terminal includes the following visual components: a label displaying the teacher location information; Three buttons locate the teacher coordinates, scan the student coordinates to display in the list, and clear the list; Display the list display box of class information of each student; Horizontal layout for placing three buttons. The non visual component includes: a position sensor for obtaining the current position information; A web-based microdatabase is used to store the location coordinates of teachers and the distance between students and teachers.Set the properties of the teacher component as follows. Horizontal alignment of screen 1 is on the left and vertical at the top, and scrolling is allowed to be true; The text of the label is my position and font size is 24; The button text is position, scan, empty, and font size is 18; Horizontal and vertical alignment of horizontal layout are centered, height is automatic and width is sufficient; Finally, set the server address of the network microdatabase.