java - How to avoid nested ActionListeners? -

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in program, want user to:

  1. pick/open database (like access) on own
  2. pick table database
  3. select column(s) table

in code, have class this:

mntmopendatabase.addactionlistener(new actionlistener() {     public void actionperformed(actionevent e) {         //open database         //display tables buttons         tablebutton.addactionlistener(new actionlistener() { // select table             public void actionperformed(actionevent e) {                 //display columns of table selected buttons                     colbutton.addactionlistener(new actionlistener() {                         public void actionperformed(actionevent e) {// add list of columns exported }

and results big block of code. there cleaner, simpler way this?

the solution refactor:

  • create separate , separately testable class code open database.
  • and separate , separately testable class display of data.
  • in actionlistener, either create instances of these classes, or interact them, if exist.
  • learn basic principles of m-v-c (model-view-control) design pattern, , use them. don't have slavish them, , lord-knows there many variants, overall guiding principles should @ least respected.
  • strive make gui or view dumb possible. knows how display data, has facilities allow control update display, , knows how notify control when user interacts it, , that's it.
  • side recommendation 1: sure database interaction done in background thread.
  • side recommendation 2: sure swing interaction done in on swing edt (the event-dispatch thread).

please @ similar more complete question , answer: how can 1 best avoid writing bloated gui code?. answers gets, , wish up-vote them gazillion times.

for example, code above simple as:

mntmopendatabase.addactionlistener(new actionlistener() {     public void actionperformed(actionevent e) {         control.opendatabase();     } }

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