Solved

Positionin a popup menu

Posted on 1998-02-20
3
256 Views
Last Modified: 2010-04-16
I am creating a Swing-based application. One of the frames in that application displays a tree. When user clicks with a right mouse button on a tree node a popup menu apperas. My question is related to the positioning of that menu.

Does anyone has a code or an algorithm which allows to position a popup menu in such a way that the menu is always completely visible (that is it is not completetly or partially hidden by the edge of the screen or edge of the parent frame. That means it has to be positioned based on the cursor location as well as various edges.  I am looking for a behavior similar to that of popup menus in Microsoft Windows Explorer in 95 and NT.

I am not looking for a general description of the approach I shoud take but rather for an exact algorithm or even better a code which implements such behavior.
0
Comment
Question by:msmolyak
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
3 Comments
 
LVL 3

Accepted Solution

by:
gwalters earned 200 total points
ID: 1233171
Dimension sz=menu.size();
Dimension scrsz=Toolkit.getDefaultToolkit.getScreenSize();
Point loc=CURSOR_LOCATION;
menu.move(Math.max(loc.x,scrsz.width-sz.width),Math.max(loc.y,scrsz.height-sz.height));




I put a holder for CURSOR_LOCATION because, without your code, I didn't know how you would get that.

Basically, the x,y coordinate of the click is the preferred location.  Move it up or to the left if putting it there would cause it to be offscreen.
0
 
LVL 3

Expert Comment

by:gwalters
ID: 1233172
Oops, those should be Math.min, not Math.max!

sorry.
0
 
LVL 5

Author Comment

by:msmolyak
ID: 1233173
I slightly modified you logic to come up with

// Position the menu on the screen
Dimension sz=menu.size();
Dimension scrsz=Toolkit.getDefaultToolkit().getScreenSize();
if (scrsz.width - (parentFrame.getLocationOnScreen().x + x) < sz.width)
{
    // If the cursor is close to the right edge of the screen,
    // position the menu to the left of the cursor
    x = (parentFrame.getLocationOnScreen().x + x) - sz.width;
}
else
{
    // Position the menu to the right of the cursor
    x = parentFrame.getLocationOnScreen().x + x + 10;
}
y = Math.min(parentFrame.getLocationOnScreen().y + y + 25,
             scrsz.height-sz.height);

this.menu.setLocation(x,y);

Thanks for your help.
0

Featured Post

Revamp Your Training Process

Drastically shorten your training time with WalkMe's advanced online training solution that Guides your trainees to action.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

For beginner Java programmers or at least those new to the Eclipse IDE, the following tutorial will show some (four) ways in which you can import your Java projects to your Eclipse workbench. Introduction While learning Java can be done with…
Java had always been an easily readable and understandable language.  Some relatively recent changes in the language seem to be changing this pretty fast, and anyone that had not seen any Java code for the last 5 years will possibly have issues unde…
Viewers learn about the scanner class in this video and are introduced to receiving user input for their programs. Additionally, objects, conditional statements, and loops are used to help reinforce the concepts. Introduce Scanner class: Importing…
Viewers will learn one way to get user input in Java. Introduce the Scanner object: Declare the variable that stores the user input: An example prompting the user for input: Methods you need to invoke in order to properly get  user input:

617 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question