我是黑莓新手，我想创建一个自定义textArea。输入40个字母后，它应自动更改该行。在更多行之后，显示垂直滚动选项。 请任何给我发送代码或告诉我程序
答案 0 :(得分：0)
package max;
import net.rim.device.api.math.Fixed32;
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.system.Characters;
import net.rim.device.api.system.Display;
import net.rim.device.api.system.EncodedImage;
import net.rim.device.api.ui.component.EditField;
import net.rim.device.api.ui.component.PasswordEditField;
import net.rim.device.api.ui.container.VerticalFieldManager;
import net.rim.device.api.ui.*;
public class TextArea extends VerticalFieldManager implements FocusChangeListener, FieldChangeListener {
/**
* Default margins
*/
private final static int DEFAULT_LEFT_MARGIN = 1;
private final static int DEFAULT_RIGHT_MARGIN =5;
private final static int DEFAULT_TOP_MARGIN = 0;
private final static int DEFAULT_BOTTOM_MARGIN = 0;
/**
* Default paddings
*/
private final static int DEFAULT_LEFT_PADDING = 0;
private final static int DEFAULT_RIGHT_PADDING =0;
private final static int DEFAULT_TOP_PADDING =0;
private final static int DEFAULT_BOTTOM_PADDING=0;
//private static final int TYPE_PASSWORD = 0;
/**
* Margins around the text box
*/
private int topMargin = DEFAULT_TOP_MARGIN;
private int bottomMargin = DEFAULT_BOTTOM_MARGIN;
private int leftMargin = DEFAULT_LEFT_MARGIN;
private int rightMargin = DEFAULT_RIGHT_MARGIN;
/**
* Padding around the text box
*/
private int topPadding = DEFAULT_TOP_PADDING;
private int bottomPadding = DEFAULT_BOTTOM_PADDING;
private int leftPadding = DEFAULT_LEFT_PADDING;
private int rightPadding = DEFAULT_RIGHT_PADDING;
private boolean ignoreChange = false;
private int totalHorizontalEmptySpace = leftMargin + leftPadding
+ rightPadding + rightMargin;
/**
* Amount of empty space vertically around the text box
*/
private int totalVerticalEmptySpace = topMargin + topPadding
+ bottomPadding + bottomMargin;
/**
* Minimum height of the text box required to display the text entered
*/
private int minHeight = getFont().getHeight() + totalVerticalEmptySpace;
/**
* Width of the text box
*/
private int width =Display.getWidth();
/**
* Height of the text box
*/
private int height = minHeight;
/**
* Background image for the text box
*/
private EncodedImage backgroundImage;
private EncodedImage focusedBackgroundImage;
/**
* Bitmap version of the backgroundImage.
* Needed to reduce the calculation overhead incurred by
* scaling of the given image
* and derivation of Bitmap from the
* EncodedImage every time it is needed.
*/
//private int focus_color = AppColors.FOCUS_COLOR;
private int focus_color = AppColors.FOCUS_COLOR;
private Bitmap bitmapBackgroundImage;
private Bitmap focusedBitmapBackgroundImage;
//private EditField editField;
/**
* The core element of this text box
*/
// public static final int TYPE_PASSWORD=2;
// public static final int TYPE_PLAIN=1;
// private BasicEditField editField;
// public TextArea(int type)
// {
// // Let the super class initialize the core
// super(0);
//// this.type = type;
// VerticalFieldManager vfm=new VerticalFieldManager(Manager.VERTICAL_SCROLL);
// if (type!=TYPE_PASSWORD) {
// // An edit field is the sole field of this manager.
// editField = new EditField(FIELD_VCENTER);
// }else{
// editField = new PasswordEditField();
// editField.setMaxSize(12);
// }
// //editField = new CustomEditField();
// vfm.add(editField);
// add(vfm);
// vfm.setFocusListener(this);
//
// }
public EditField objEditField;
public TextArea(int w,int h, EncodedImage backgroundImage, EncodedImage focusedState)
{
this.width=w;
this. height=h;
VerticalFieldManager vfm=new VerticalFieldManager(Manager.VERTICAL_SCROLL);
setFocusedBackgroundImage(backgroundImage);
if(focusedState==null){
focusedState = backgroundImage;
}
setFocusedBackgroundImage(focusedState);
vfm.add(objEditField);
add(vfm);
vfm.setFocusListener(this);
//
objEditField.setFocusListener(this);
}
// private void setFocusedBackgroundImage(EncodedImage focusedState) {
// // TODO Auto-generated method stub
//
// }
public TextArea(int w,int h) {
// TODO Auto-generated constructor stub
super(Manager.NO_HORIZONTAL_SCROLL);
this.width=w;
this.height=h;
VerticalFieldManager vfm=new VerticalFieldManager(Manager.VERTICAL_SCROLL);
objEditField=new EditField()
{
// public void paint(Graphics g)
// {
// getManager().invalidate();
// super.paint(g);
//
// }
};
vfm.add(objEditField);
add(vfm);
}
public void setSize(int width, int height)
{
boolean isChanged = false;
if (width > 0 // Ignore invalid width
&& this.width != width)
{
this.width = width;
isChanged = true;
}
// Ignore the specified height if it is less
// than the minimum height required to display the text.
if (height > minHeight && height != this.height)
{
this.height = height;
isChanged = true;
}
// If width/height has been changed and background image
// is available, adapt it to the new dimension
if (isChanged == true && backgroundImage != null)
{
bitmapBackgroundImage = getScaledBitmapImage(backgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
focusedBitmapBackgroundImage = getScaledBitmapImage(focusedBackgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
}
// int actualHeight = getFont().getHeight();
// if(height>actualHeight){
// yTranslate = (height - actualHeight)/2;
// }
}
public void setWidth(int width)
{
if (width > 0 && width != this.width)
{
this.width = width;
// If background image is available, adapt it to the new width
if (backgroundImage != null)
{
bitmapBackgroundImage = getScaledBitmapImage(backgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
focusedBitmapBackgroundImage = getScaledBitmapImage(focusedBackgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
}
}
}
public void setHeight(int height)
{
// Ignore the specified height if it is
// less than the minimum height required to display the text.
if (height > minHeight)
{
this.height = height;
// If background image is available, adapt it to the new width
if (backgroundImage != null)
{
bitmapBackgroundImage = getScaledBitmapImage(backgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
focusedBitmapBackgroundImage = getScaledBitmapImage(focusedBackgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
}
}
}
public void setBackgroundImage(EncodedImage backgroundImage)
{
this.backgroundImage = backgroundImage;
// Consider the height of background image in
// calculating the height of the text box.
// setHeight() does not ensure that specified
// height will be in effect, of course, for valid reasons.
// So derivation of Bitmap image in the setHeight() method is not sure.
setHeight(backgroundImage.getHeight() + topMargin + bottomMargin);
if (bitmapBackgroundImage == null)
{
bitmapBackgroundImage = getScaledBitmapImage(backgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
}
}
public void setFocusedBackgroundImage(EncodedImage backgroundImage)
{
this.focusedBackgroundImage = backgroundImage;
// Consider the height of background image in
// calculating the height of the text box.
// setHeight() does not ensure that specified
// height will be in effect, of course, for valid reasons.
// So derivation of Bitmap image in the setHeight() method is not sure.
setHeight(backgroundImage.getHeight() + topMargin + bottomMargin);
if (focusedBitmapBackgroundImage == null)
{
focusedBitmapBackgroundImage = getScaledBitmapImage(backgroundImage,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin));
}
}
private Bitmap getScaledBitmapImage(EncodedImage image, int width, int height)
{
// Handle null image
if (image == null)
{
return null;
}
int currentWidthFixed32 = Fixed32.toFP(image.getWidth());
int currentHeightFixed32 = Fixed32.toFP(image.getHeight());
int requiredWidthFixed32 = Fixed32.toFP(width);
int requiredHeightFixed32 = Fixed32.toFP(height);
int scaleXFixed32 = Fixed32.div(currentWidthFixed32, requiredWidthFixed32);
int scaleYFixed32 = Fixed32.div(currentHeightFixed32, requiredHeightFixed32);
image = image.scaleImage32(scaleXFixed32, scaleYFixed32);
return image.getBitmap();
}
// protected void sublayout(int width, int height)
// {
// // We have one and only child - the edit field.
// // Place it at the appropriate place.
// Field field = getField(0);
// layoutChild(field, this.width - totalHorizontalEmptySpace,
// this.height - totalVerticalEmptySpace);
// setPositionChild(field, leftMargin+leftPadding, topMargin+topPadding);
//
// setExtent(this.width, this.height);
// }
public void paint(Graphics g)
{
// super.paint(g);
// if(isFocus()){
// g.setColor(Color.AQUA);
// }else{
// g.setColor(Color.BLACK);
// }
// //g.drawRect(0, 0, getWidth(), getHeight());
// g.drawRoundRect(leftMargin, topMargin,
// width - (leftMargin+rightMargin),
// height - (topMargin+bottomMargin), 5, 5);
int prevColor = g.getColor();
if (bitmapBackgroundImage == null)
{
//graphics.drawRect(leftMargin, topMargin, width - (leftMargin+rightMargin), height - (topMargin+bottomMargin));
if(isFocus()){
g.setColor(focus_color);
}
else{
g.setColor(Color.BLACK);
}
g.drawRoundRect(leftMargin, topMargin,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin), 5, 5);
g.setColor(Color.BLACK);
invalidate();
}
else
{
if(isFocus()){
g.setColor(Color.AQUA);
// g.setColor(Color.WHITE);
g.drawBitmap(leftMargin, topMargin,
this.width - (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin),
focusedBitmapBackgroundImage, 0, 0);
}else{
g.setColor(Color.BLACK);
g.drawBitmap(leftMargin, topMargin,
this.width- (leftMargin+rightMargin),
this.height - (topMargin+bottomMargin),
bitmapBackgroundImage, 0, 0);
}
}
EditField objEditField=new EditField();
String entireText = objEditField.getText();
boolean longText = false;
String textToDraw = "";
Font font = getFont();
int availableWidth = width - totalHorizontalEmptySpace;
if (font.getAdvance(entireText) <= availableWidth)
{
textToDraw = entireText;
}
else
{
int endIndex = entireText.length();
for (int beginIndex = 1; beginIndex < endIndex; beginIndex++)
{
textToDraw = entireText.substring(beginIndex);
if (font.getAdvance(textToDraw) <= availableWidth)
{
longText = true;
break;
}
}
}
if (longText == true)
{
// Force the edit field display only the truncated text
objEditField.setText(textToDraw);
// Now let the components draw themselves
// graphics.translate(0, yTranslate);
super.paint(g);
// graphics.translate(0, -yTranslate);
// Return the text field its original text
objEditField.setText(entireText);
}
else
{
// graphics.translate(0, yTranslate);
super.paint(g);
// graphics.translate(0, -yTranslate);
}
//g.setColor(Color.WHITE);
g.setColor(prevColor);
}
protected void sublayout(int width1, int height1)
{
// We have one and only child - the edit field.
// Place it at the appropriate place.
if(width==0)
{
width=width1;
}
if(height==0)
{
height=height1;
}
// super.sublayout(this.width - totalHorizontalEmptySpace,this.height - totalVerticalEmptySpace);
// setExtent(this.width, this.height);
Field field = getField(0);
layoutChild(field, this.width - totalHorizontalEmptySpace,
this.height - totalVerticalEmptySpace);
setPositionChild(field, leftMargin+leftPadding, topMargin+topPadding);
setExtent(this.width, this.height);
}
public int getPreferredWidth()
{
return width;
}
public int getPreferredHeight()
{
return height;
}
public void setTopMargin(int topMargin)
{
this.topMargin = topMargin;
}
public void setBottomMargin(int bottomMargin)
{
this.bottomMargin = bottomMargin;
}
// protected boolean keyChar(char ch, int status, int time)
// {
// if (ch == Characters.ENTER)
// {
// return true;
// }
// else
// {
// return super.keyChar(ch, status, time);
// }
// }
public String getText()
{
return objEditField.getText();
}
public void setText(String str)
{
objEditField.setText(str);
}
public void setChangeListner(){
objEditField.setChangeListener(new FieldChangeListener() {
public void fieldChanged(Field field, int context) {
}
});
}
public void fieldChanged(Field field, int context) {
if (!ignoreChange) {
EditField textField = (EditField) field;
textChanged(textField.getText());
}
}
public void textChanged(String text){
}
public void startListning(){
ignoreChange = false;
}
public void focusChanged(Field field, int eventType) {
invalidate();
}
public void addTextChangeListner(){
objEditField.setChangeListener(this);
}
public void removeTextChangeListner() {
objEditField.setChangeListener(null);
}
}
I thinks this code will help you.