fgdata/gui/dialogs/NTPS_target_task.xml

<?xml version="1.0"?>
<PropertyList>
  <name>NTPS-target-task</name>
  <layout>vbox</layout>

  <nasal>
    <open>
      p = props.globals.getNode("/sim/gui/dialogs/NTPS/task", 1);
      mode = {
        straight: p.getNode("straight", 1),
        turns:    p.getNode("turns", 1),
        pitch:    p.getNode("pitch", 1),
        both:     p.getNode("both", 1),
      };

      set_radio = func(m) {
        foreach (k; keys(mode)) {
          mode[k].setBoolValue(m == k);
        }
      }

      initialized = 0;
      foreach (k; keys(mode)) {
        if (mode[k].getType() == "NONE") {
          mode[k].setBoolValue(0);
        }
        initialized += mode[k].getBoolValue();
      }
      if (!initialized) {
        set_radio("straight");
      }
    </open>

    <close># just kept for educational purposes :-)</close>
  </nasal>

  <text>
   <label>Target Task Selection</label>
  </text>

  <hrule/>

  <group>
    <layout>hbox</layout>
    <default-padding>8</default-padding>

    <group>
     <layout>table</layout>
     <radio>
      <row>0</row><col>0</col>
      <property>/sim/gui/dialogs/NTPS/task/straight</property>
      <live>true</live>
      <binding>
       <command>nasal</command>
       <script>set_radio("straight"); setprop("/autopilot/lead-target/task", "straight")</script>
      </binding>
     </radio>
     <text>
      <label>Straight and Level</label>
      <halign>left</halign>
      <row>0</row><col>1</col>
     </text>

     <radio>
      <row>1</row><col>0</col>
      <property>/sim/gui/dialogs/NTPS/task/turns</property>
      <live>true</live>
      <binding>
       <command>nasal</command>
       <script>set_radio("turns"); setprop("/autopilot/lead-target/task", "turns");</script>
      </binding>
     </radio>
     <text>
      <label>Level Turns</label>
      <halign>left</halign>
      <row>1</row><col>1</col>
     </text>

     <radio>
      <row>2</row><col>0</col>
      <property>/sim/gui/dialogs/NTPS/task/pitch</property>
      <live>true</live>
      <binding>
       <command>nasal</command>
       <script>set_radio("pitch"); setprop("/autopilot/lead-target/task", "pitch");</script>
      </binding>
     </radio>
     <text>
      <label>Straight Pitch Changes</label>
      <halign>left</halign>
      <row>2</row><col>1</col>
     </text>

     <radio>
      <row>3</row><col>0</col>
      <property>/sim/gui/dialogs/NTPS/task/both</property>
      <live>true</live>
      <binding>
       <command>nasal</command>
       <script>set_radio("both"); setprop("/autopilot/lead-target/task", "lazy-eights");</script>
      </binding>
     </radio>
     <text>
      <label>Lazy Eights</label>
      <halign>left</halign>
      <row>3</row><col>1</col>
     </text>

    </group>
   </group>

  <button>
    <legend>Close</legend>
    <default>true</default>
    <key>Esc</key>
    <padding>10</padding>
    <binding>
      <command>dialog-apply</command>
    </binding>
    <binding>
      <command>dialog-close</command>
    </binding>
  </button>

</PropertyList>