Below class is a textbox field. Can this be modified so that when the textbox is filled with text and user keeps type the text then scrolls ? Whats happening now is that once the textbox is filled with text any subsequent text that is typed is not being displayed.
Thanks
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 re开发者_JAVA技巧turn 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);
}
}
This will help you to get started. It is a simplified version of the ScrollableEditField
that I am using. I coded it before touch BlackBerry devices became available, therefore some additional work is required here to support TouchEvent
s.
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);
}
}
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