33. Java graphical interface design--null layout of layout manager (empty layout)

Excerpted from http://blog.csdn.net/liujun13579/article/details/7774267

33. Java graphical interface design--null layout of layout manager (empty layout)

The general container has a default layout, but sometimes you need to specify the size and location of each build, and you need to use an empty layout.

Operation Method:

1) First Use the setlayout (NULL) statement to set the container's layout to a null layout (empty layout).

2) re-call the component's setbounds (int x, int y, int width,int height) method to set the size and position of the component in the container, in pixels.

• X is the distance of the left edge of the control from the left edge of the form
• Y is the distance of the top edge of the control from the top edge of the form
• Width for control widths
• Height for control Heights

Example: Using an empty layout to pinpoint the position of a component

1 //Nulllayoutdemo.java2 3 Importjava.awt.*;4 5 Importjavax.swing.*;6 7  Public classnulllayoutdemo{8 9 JFrame fr;Ten  One JButton A, b; A  - Nulllayoutdemo () { -  theFR =NewJFrame (); -  -Fr.setbounds (100,100,250,150); -  +          //set form to empty layout -  +Fr.setlayout (NULL); A  atA=NewJButton ("button a"); -  -b=NewJButton ("button B"); -  - Fr.getcontentpane (). Add (a); -  in          //set the exact position of button a -  toA.setbounds (30,30,80,25); +  - Fr.getcontentpane (). Add (b); the  *B.setbounds (150,40,80,25); $ Panax NotoginsengFr.settitle ("Nulllayoutdemo"); -  theFr.setvisible (true); +  A fr.setdefaultcloseoperation (jframe.exit_on_close); the  +Fr.setlocationrelativeto (NULL);//to center the form on the display -  $   } $  -    Public Static voidMain (String args[]) { -  the     NewNulllayoutdemo (); - Wuyi   } the  -}

The results of the program run as follows:

33. Java graphical interface design--null layout of layout manager (empty layout)