使用LWUIT UI庫，我不會破壞J2ME應用程序

Question

我使用LWUIT J2ME工作，我有一個問題是，

當我startApp()裏面的MIDlet我第一次Display.init(this)

和運行應用程序LWUIT工作好但是當我在MIDlet的利用內幕startApp()事件的形式，它很好的工作，但這種形式的ActionEvent我稱之爲新的形式和新形式 我把一個命令時，我按下它，它在主MIDlet不動

請幫助我如何知道lwuit使用

import javax.microedition.MIDlet; 

import some lwuit UILibrary 

public class mainMiddlet extends MIDlet implement ActionListner 
{ 
     public mainMiddlet(){ 
        try{ 

         Display.init(this); 
         //somthing is here 
         form=new Form(); 

         form.addActionListener(this); 

        }catch(Exception e){} 
     } 
     public void actionperformed(ActionEven ae){ 
       //here i call new form 
       //in action event of this form 
       new form().show(); 
     } 
     //here some middlet default method 


} 
public class newForm extends Form { 

    //in this form I am put one command back and when i am pressed it 
    // I call mainMiddlet but it throw error internal application java.lang.nullpointer 
    // can I back on mainmiddlet from on form to another form 
    // my main problem is I am not move on mainmiddlet for exit middlet because destoryall() 
    // is method of middlet 

} 

Answer 1

它只是簡單。您可以在下一個表格返回命令中調用show()方法。例如，

MainMidlet.java

// create the midlet and write inside of the midlet 
final Form form = new Form(); 

form.addCommand(new Command("Next") { 

    public void actionPerformed(ActionEvent evt) { 
      new NewForm(form).show(); 
     } 
    }); 

NewForm.java

// create the NewForm class and write inside of the class 

     public NewForm(final Form form) { 
    // Constructor 
     addCommand(new Command("Back") { 

      public void actionPerformed(ActionEvent evt) { 
        form.show(); 
       } 
      }); 
    }