自定义编辑字段不显示所有键入的文本

Question

下面的类是一个文本框字段。这可以修改，以便当文本框填充文本和用户保持键入文本然后滚动？现在发生的事情是，一旦文本框被填充文本，任何后续输入的文本都不会被显示。

感谢

import net.rim.device.api.ui.Color; 
import net.rim.device.api.ui.Font; 
import net.rim.device.api.ui.Graphics; 
import net.rim.device.api.ui.component.EditField; 

public class CustomEditField extends EditField { 
    // private members of the CustomEditField class 
    private Font defaultFont; 
    // used to get the default font 
    private String text; 

    // used to specify the default width of the table cells 

    // constructor calls the super class constructor 
    public CustomEditField(String label, String initialValue, int maxNumChars, 
      long style) { 
     super(label, initialValue, maxNumChars, style); 
    } 

    // overrides the default getPreferredWidth functionality to return a fixed 
    // width 
    public int getPreferredWidth() { 
     defaultFont = Font.getDefault(); 
     text = "0000000000"; 
     return defaultFont.getAdvance(text); 

    } 

    // overrides the default layout functionality to set the width of the table 
    // cell 
    protected void layout(int width, int height) { 
     width = getPreferredWidth(); 
     height = super.getPreferredHeight(); 
     super.layout(width, height); 
     // uses the super class' layout functionality 
     // after the width and the height are set 
     super.setExtent(width, height); 
     // uses the super class' setExtent functionality 
     // after the width and the height are set 
    } 

    public void paint(Graphics graphics){ 

     graphics.setBackgroundColor(Color.LIGHTBLUE); 
     super.paint(graphics); 
    } 

} 

Answer 1

这将帮助你上手。这是我正在使用的ScrollableEditField的简化版本。我在黑莓设备可用之前编码它，因此需要一些额外的工作来支持TouchEvent。

class ScrollableEditField extends Manager { 
    private final static int  DEFAULT_TOP_PADDING  = 1; 
    private final static int  DEFAULT_BOTTOM_PADDING = 1; 
    private final static int  DEFAULT_LEFT_PADDING = 1; 
    private final static int  DEFAULT_RIGHT_PADDING = 1; 

    private int      TOTAL_VERTICAL_PADDING = DEFAULT_TOP_PADDING + DEFAULT_BOTTOM_PADDING; 
    private int      TOTAL_HORIZONTAL_PADDDING = DEFAULT_LEFT_PADDING + DEFAULT_RIGHT_PADDING; 

    private int      width = -1; 
    private int      height = -1; 

    private HorizontalFieldManager hfm = new HorizontalFieldManager(HORIZONTAL_SCROLL); 
    private EditField    ef; 

    public ScrollableEditField(String label, String initialValue, int maxNumChars, long innerEditFieldStyle) { 
     super(NO_HORIZONTAL_SCROLL); 
     ef = new EditField(label, initialValue, maxNumChars, innerEditFieldStyle); 
     hfm.add(ef); 
     add(hfm); 
    } 

    protected void sublayout(int width, int height) { 
     if (this.width != -1) { 
      width = this.width; 
     } 

     if (this.height != -1) { 
      height = this.height; 
     } else { 
      height = ef.getFont().getHeight(); 
     } 

     layoutChild(hfm, width-TOTAL_HORIZONTAL_PADDDING, height-TOTAL_VERTICAL_PADDING); 
     setPositionChild(hfm, DEFAULT_LEFT_PADDING, DEFAULT_TOP_PADDING); 
     setExtent(width, height); 
    }  

    public EditField getEditField() { 
     return ef; 
    } 

    public void setWidth(int width) { 
     this.width = width; 
    } 

    protected void onFocus(int direction) { 
     super.onFocus(direction); 
     ef.setCursorPosition(0); 
    } 

    protected void onUnfocus() { 
     hfm.setHorizontalScroll(0); 
     super.onUnfocus(); 
    } 
}; 

public class ScrollableEditFieldScreen extends MainScreen { 
    public ScrollableEditFieldScreen() { 
     super(NO_VERTICAL_SCROLL); 
     setTitle("ScrollableEditField"); 

     // hfm1 and hfm2 are here just to position the ScrollableEditField in the center of the screen 
     HorizontalFieldManager hfm1 = new HorizontalFieldManager(USE_ALL_HEIGHT | FIELD_HCENTER); 
     HorizontalFieldManager hfm2 = new HorizontalFieldManager(FIELD_VCENTER); 

     // instantiating the scrollable edit field and adding border 
     ScrollableEditField sef = new ScrollableEditField("", "", 50, 0); 
     sef.setBorder(BorderFactory.createRoundedBorder(new XYEdges(5,5,5,5))); 
     sef.setWidth(sef.getFont().getAdvance('0')*10); 

     hfm2.add(sef); 
     hfm1.add(hfm2); 
     add(hfm1); 
    } 
}