将数据保存到黑莓内存

Question

我有一个应用程序，当我们点击开始时显示一个测试屏幕。现在我添加了一个简历测试按钮，&想要从退出的位置显示问题。为此，我想将问题保存到内存中，以便我可以从中取出&显示它。我写的代码，plz帮助

package com.firstBooks.series.ui.screens; 

import net.rim.device.api.ui.Field; 
import net.rim.device.api.ui.FieldChangeListener; 
import net.rim.device.api.ui.Graphics; 
import net.rim.device.api.ui.Manager; 
import net.rim.device.api.ui.MenuItem; 
import net.rim.device.api.ui.UiApplication; 
import net.rim.device.api.ui.component.LabelField; 
import net.rim.device.api.ui.component.Menu; 
import net.rim.device.api.ui.component.NullField; 
import net.rim.device.api.ui.container.HorizontalFieldManager; 

import net.rim.device.api.ui.container.VerticalFieldManager; 
import java.lang.String; 
import com.firstBooks.series.AppConfig; 
import com.firstBooks.series.db.DBMain; 
import com.firstBooks.series.db.Question; 
import com.firstBooks.series.db.parser.XMLParser; 
import com.firstBooks.series.ui.UIinitialize; 
import com.firstBooks.series.ui.managers.TopManager; 
import com.vensi.api.ImgButtonField; 

public class TestScreen extends ScreenManager implements AppConfig{ 

TopManager topManager = null; 
VerticalFieldManager middleManager = null; 
HorizontalFieldManager manager = null; 
ImgButtonField A, B, C, D; 
//static PersistentObject Store; 
static int quesNum[]; 
int quesNumber;//quesnumberTest[]; 
LabelField question1, blank, choice1Label, choice2Label, choice3Label, 
     choice4Label; 
FieldChangeListener checkAnswerListenerA, checkAnswerListenerB, 
     checkAnswerListenerC, checkAnswerListenerD; 

public TestScreen() { 
    super(); 
    drawScreen(); 
} 
//static { 
    //Store = PersistentStore.getPersistentObject(0x3097b5a0b70e028fL); 
//} 
public void drawScreen() { 

    topManager = new TopManager(newTestButton, 0); 

    middleManager = new VerticalFieldManager(
      VerticalFieldManager.VERTICAL_SCROLL 
        | VerticalFieldManager.VERTICAL_SCROLLBAR 
        | VerticalFieldManager.USE_ALL_WIDTH 
        | Field.FIELD_HCENTER) { 
     protected void sublayout(int maxWidth, int maxHeight) { 
      // maxwidth reduced by 15 to get padding along the edges 
      super.sublayout(maxWidth - 15, maxHeight - 10); 

      if (UIinitialize.displayType == Device_Storm) { 
       setExtent(maxWidth - 15, 347); 
      } else if (UIinitialize.displayType == Device_Tour) { 
       setExtent(maxWidth - 15, 263); 
      } else if (UIinitialize.displayType == Device_Curve) { 
       setExtent(maxWidth - 10, 165); 
      } 

     } 
    }; 

    A = new ImgButtonField(buttonABkGrndDown, buttonABkGrnd, 
      Field.FOCUSABLE | Field.FIELD_HCENTER); 
    B = new ImgButtonField(buttonBBkGrndDown, buttonBBkGrnd, 
      Field.FOCUSABLE | Field.FIELD_HCENTER); 
    C = new ImgButtonField(buttonCBkGrndDown, buttonCBkGrnd, 
      Field.FOCUSABLE | Field.FIELD_HCENTER); 
    D = new ImgButtonField(buttonDBkGrndDown, buttonDBkGrnd, 
      Field.FOCUSABLE | Field.FIELD_HCENTER); 


     manager = new HorizontalFieldManager(Manager.NO_HORIZONTAL_SCROLL 
      | Manager.NO_VERTICAL_SCROLL | Field.USE_ALL_WIDTH 
      | Field.USE_ALL_HEIGHT) { 
     protected void sublayout(int maxWidth, int maxHeight) { 

      if (UIinitialize.displayType == Device_Storm) { 
       layoutChild(A, buttonABkGrnd.getWidth(), buttonABkGrnd 
         .getHeight()); 
       setPositionChild(A, 25, 9); 

       layoutChild(B, buttonBBkGrnd.getWidth(), buttonBBkGrnd 
         .getHeight()); 
       setPositionChild(B, 115, 9); 

       layoutChild(C, buttonCBkGrnd.getWidth(), buttonCBkGrnd 
         .getHeight()); 
       setPositionChild(C, 205, 9); 

       layoutChild(D, buttonDBkGrnd.getWidth(), buttonDBkGrnd 
         .getHeight()); 
       setPositionChild(D, 295, 9); 

      } else if (UIinitialize.displayType == Device_Tour) { 
       layoutChild(A, buttonABkGrnd.getWidth(), buttonABkGrnd 
         .getHeight()); 
       setPositionChild(A, 41, 9); 

       layoutChild(B, buttonBBkGrnd.getWidth(), buttonBBkGrnd 
         .getHeight()); 
       setPositionChild(B, 161, 9); 

       layoutChild(C, buttonCBkGrnd.getWidth(), buttonCBkGrnd 
         .getHeight()); 
       setPositionChild(C, 281, 9); 

       layoutChild(D, buttonDBkGrnd.getWidth(), buttonDBkGrnd 
         .getHeight()); 
       setPositionChild(D, 401, 9); 
      } else if (UIinitialize.displayType == Device_Curve) { 
       layoutChild(A, buttonABkGrnd.getWidth(), buttonABkGrnd 
         .getHeight()); 
       setPositionChild(A, 33, 19); 

       layoutChild(B, buttonBBkGrnd.getWidth(), buttonBBkGrnd 
         .getHeight()); 
       setPositionChild(B, 107, 19); 

       layoutChild(C, buttonCBkGrnd.getWidth(), buttonCBkGrnd 
         .getHeight()); 
       setPositionChild(C, 182, 19); 

       layoutChild(D, buttonDBkGrnd.getWidth(), buttonDBkGrnd 
         .getHeight()); 
       setPositionChild(D, 257, 19); 
      } 

      setExtent(maxWidth, maxHeight); 
     } 

     protected void paint(Graphics g) { 
      super.paint(g); 
     } 
    }; 

    String title = ""; 

    quesNumber = DBMain.getQuestionNumber(); 
    System.out.println("the value of QUESNUMBER IS:"+quesNumber); 
    DBMain.curQuestion = (Question) XMLParser.questionList 
      .elementAt(quesNumber); 
    title = DBMain.curQuestion.getTitle(); 

    String BlankSpace = " "; 
    String choice1 = "A. " + DBMain.curQuestion.getChoice1() + "\n" + " "; 
    String choice2 = "B. " + DBMain.curQuestion.getChoice2() + "\n" + " "; 
    String choice3 = "C. " + DBMain.curQuestion.getChoice3() + "\n" + " "; 
    String choice4 = "D. " + DBMain.curQuestion.getChoice4() + "\n" + " "; 

    question1 = new LabelField(title); 
    question1.setFont(myFontBoldSmall()); 

    blank = new LabelField(BlankSpace); 
    blank.setFont(myFontBoldSmall()); 

    choice1Label = new LabelField(choice1); 
    choice1Label.setFont(myFontPlainSmall()); 
    choice2Label = new LabelField(choice2); 
    choice2Label.setFont(myFontPlainSmall()); 
    choice3Label = new LabelField(choice3); 
    choice3Label.setFont(myFontPlainSmall()); 
    choice4Label = new LabelField(choice4); 
    choice4Label.setFont(myFontPlainSmall()); 

    DBMain.answer = DBMain.curQuestion.getAnswer(); 
    //synchronized (Store) { 
     //Store.setContents(quesNumber+""); 

     //Store.commit(); 

    //} 

    checkAnswerListenerA = new FieldChangeListener() { 

     public void fieldChanged(Field field, int context) { 
      DBMain.selectedAnswer = "A"; 
      UiApplication.getUiApplication().pushScreen(new AnswerScreen()); 
      UiApplication.getUiApplication().popScreen(getScreen()); 

     } 
    }; 
    A.setChangeListener(checkAnswerListenerA); 
    checkAnswerListenerB = new FieldChangeListener() { 

     public void fieldChanged(Field field, int context) { 
      DBMain.selectedAnswer = "B"; 
      UiApplication.getUiApplication().pushScreen(new AnswerScreen()); 
      UiApplication.getUiApplication().popScreen(getScreen()); 
     } 
    }; 
    B.setChangeListener(checkAnswerListenerB); 

    checkAnswerListenerC = new FieldChangeListener() { 

     public void fieldChanged(Field field, int context) { 
      DBMain.selectedAnswer = "C"; 
      UiApplication.getUiApplication().pushScreen(new AnswerScreen()); 
      UiApplication.getUiApplication().popScreen(getScreen()); 
     } 
    }; 
    C.setChangeListener(checkAnswerListenerC); 

    checkAnswerListenerD = new FieldChangeListener() { 

     public void fieldChanged(Field field, int context) { 
      DBMain.selectedAnswer = "D"; 
      UiApplication.getUiApplication().pushScreen(new AnswerScreen()); 
      UiApplication.getUiApplication().popScreen(getScreen()); 
     } 
    }; 
    D.setChangeListener(checkAnswerListenerD); 
    /*A.setChangeListener(checkAnswerListenerA); 
    B.setChangeListener(checkAnswerListenerB); 
    C.setChangeListener(checkAnswerListenerC); 
    D.setChangeListener(checkAnswerListenerD);*/ 

    manager.add(new NullField(Field.FOCUSABLE)); 
    manager.add(A); 
    manager.add(B); 
    manager.add(C); 
    manager.add(D); 
    manager.add(new NullField(Field.FOCUSABLE)); 

    middleManager.add(question1); 
    middleManager.add(new NullField(Field.FOCUSABLE)); 
    middleManager.add(blank); 
    middleManager.add(choice1Label); 
    middleManager.add(new NullField(Field.FOCUSABLE)); 
    middleManager.add(choice2Label); 
    middleManager.add(new NullField(Field.FOCUSABLE)); 
    middleManager.add(choice3Label); 
    middleManager.add(new NullField(Field.FOCUSABLE)); 
    middleManager.add(choice4Label); 

    add(topManager); 
    add(middleManager); 
    add(manager); 
} 

protected void makeMenu(Menu menu, int instance) { 
    menu.add(new MenuItem("A", 20, 10) { 
     public void run() { 
      answerMenu("A"); 
     } 
    }); 
    menu.add(new MenuItem("B", 30, 20) { 
     public void run() { 
      answerMenu("B"); 
     } 
    }); 
    menu.add(new MenuItem("C", 40, 30) { 
     public void run() { 
      answerMenu("C"); 
     } 
    }); 
    menu.add(new MenuItem("D", 50, 40) { 
     public void run() { 
      answerMenu("D"); 
     } 
    }); 
    super.makeMenu(menu, instance); 
} 

private void answerMenu(String answer) { 
    DBMain.selectedAnswer = answer; 

    UiApplication.getUiApplication().pushScreen(new AnswerScreen()); 
    UiApplication.getUiApplication().popScreen(getScreen()); 

} 

protected boolean keyChar(char character, int status, int time) { 
    if (character == 'A' || character == 'a') 
     DBMain.selectedAnswer = "A"; 
    else if (character == 'B' || character == 'b') 
     DBMain.selectedAnswer = "B"; 
    else if (character == 'C' || character == 'c') 
     DBMain.selectedAnswer = "C"; 
    else if (character == 'D' || character == 'd') 
     DBMain.selectedAnswer = "D"; 
    else 
     return super.keyChar(character, status, time); 

    UiApplication.getUiApplication().pushScreen(new AnswerScreen()); 
    UiApplication.getUiApplication().popScreen(getScreen()); 
    return true; 
} 



protected void paint(Graphics g) { 
    g.drawBitmap(0, 0, UIinitialize.screenWidth, UIinitialize.screenHeight, 
      backgroundBitmap, 0, 0); 
    subpaint(g); 
    TestScreen.this.invalidate(); 
} 
} 

Answer 1

我从大的代码片断看，你有使用PersistentStore类，但被注释掉了几个代码块。您正处在正确的轨道上 - 这是将数据保存到设备闪存的正确方法。如果您对此有更具体的问题，请将您的答案细化为更具体。否则，请查看链接的javadoc，以便了解如何使用该类，包括代码示例。