Jython 使用 swing JComboBoxes 如何创建 actionPerformed 处理程序

Question

I am not that proficient in Java. I need to build a UI from a runtime script in Jython. The UI is a date picker. For backwards hardware compatibility I am forced to use JDK 1.4 as Source/Binary format, while having JDK 1.8 as platform. The rest of the GUI wirks fine.

the date picker looks like this:

all the controls, including the panel container, are built at runtime. And they are all wrapped in classes like:

class DP_Combo(JComboBox):

    def __init__(self, kwargv={}):
        
        self.setModel(jaxswing.DefaultComboBoxModel(kwargv['items']))
        self.setBounds(kwargv['bounds'][0], kwargv['bounds'][1], \
                        kwargv['bounds'][2], kwargv['bounds'][3])
        self.setFont(Font("Dialog", 1, 18))

for the ComboBoxes.

also the DatePicker itself is a class called from another script:

class DatePicker:

    def __init__(self, hiddenTabbedPane, argDate=time.strftime('%d.%m.%Y'), argSplitter="."):
       # blah bla

in the DatePicker class the ComboBoxes instances are created like this:

def __build_combos(self):
    _months = {'items': MONTHS, 'bounds': MONTHS_BOUNDS}
    _years = {'items': YEARS, 'bounds': YEARS_BOUNDS}
    self.months_list = DP_Combo(_months)
    self.years_list = DP_Combo(_years)
    # initialize combos:
    self.months_list.setSelectedIndex(self.curMonth - 1)
    self.years_list.setSelectedIndex(indexOf(self.curYear, YEARS))
    self.newPane.add(self.months_list)
    self.newPane.add(self.years_list)

Note: the items in all caps are list of months and years obv.

All good so far. Now I need to create the handlers to capture the events from the controls and assign them to the controls themselves.

for the ComboBoxes as example, I know from java:

// initializing the frame
private void initComponents() {
    // itin vars and create components - widgets       
   jComboBoxMonths = new javax.swing.JComboBox();
   // setup jComboBoxMonths 
   // ...
   jComboBoxMonths.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jComboBoxMonths_ActionPerformed(evt);
        }
    });
}

then at frame class level the event handler:

private void jComboBox3_ActionPerformed(java.awt.event.ActionEvent evt) {                                           
    // do stuff
}                                           

I am struggling to translate the above into jython, and also not sure whether the handlers can be placed inside the DatePicker class or need to be one level up.

Help please and thanx in advance for the patience

Answer 1

I don't know if this is the cleaner way, but it works.

first I had to create inner (nested) classes to grab the events, in this example the actionPerfomed event is captured and passed to the handler by myActionListener :

from java.awt import event

class DatePicker:

    def __init__(self, kwargv):
    # blah blah
    # initialize controls


    class myActionListener(event.ActionListener):

        def __init__(self, handler):
            self.handler = handler

        def actionPerformed(self, evt):
            self.handler(evt)

and when creating the combo box (DatePicker level) add an instance of the listener:

class DatePicker:
    # ...
    # init and stuff

    def crate_years_combo(self):
        self.years_combo = DP_Combo(_years)
        listener = self.myActionListener(self.years_change_evt)
        self.years_combo.addActionListener(listener)

finally (again at DatePicker level) define the method to handle the event actionPerformed (the years_change_evt ):

class DatePicker:
    # ...
    # init and stuff

    def years_change_evt(self, evt):
        # do stuff