我正在研究一个程序，非常简单。您只需在提供的字段中输入一个人的姓名即可。单击搜索，它搜索数据库并检索信息。包括图片。这工作正常，但我有一个问题。如果我使用peter进行搜索，数据库中有两个“peters”。当我滚动。除非我点击图片字段，否则图片不会改变。我相信我发布了相关代码。任何帮助将不胜感激。谢谢
public class DriverSearchResultScreen extends MainScreen implements FieldChangeListener{
LabelField header,title;
LabelField lblLicenseNumber,lblFirstName,lblLastName,lblBirthDate,lblLicenseExpiry,lblLicenseType,lblLicenseStatus;
ColoredMultiLineLabelField clblLicenseNumber,clblFirstName,clblLastName,clblBirthDate,clblLicenseExpiry,clblLicenseType,clblLicenseStatus;
CustomButtonField btnSearch;
CustomImageButton btnLeft,btnRight;
CustomImageButton bmpfDriverPhoto;
Vector licenseInfoData;
int currentIndex = 0;
public DriverSearchResultScreen(Vector licenseInfoData ) {
this.licenseInfoData = licenseInfoData;
// TODO Auto-generated constructor stub
title = new LabelField("License",LabelField.USE_ALL_WIDTH);
/*header.setBackground(bg);*/
setTitle(title);
bmpfDriverPhoto = new CustomImageButton(Bitmap.getBitmapResource("default-profile.png")){
public boolean isFocusable() { return true; };
};
bmpfDriverPhoto.setChangeListener(this);
add(bmpfDriverPhoto);
header = new LabelField("",LabelField.FIELD_HCENTER|LabelField.USE_ALL_WIDTH){
public void paint(Graphics g){
int col = g.getColor();
g.setColor(Color.YELLOW);
super.paint(g);
g.setColor(col);
}
public int getPreferredWidth(){
return net.rim.device.api.system.Display.getWidth();
}
};
this.getMainManager().setBackground(BackgroundFactory.createBitmapBackground(Bitmap.getBitmapResource("background.png")));
header.setFont(Font.getDefault().derive(Font.SANS_SERIF_STYLE|Font.BOLD,25));
add(header);
add(new SeparatorField());
Bitmap vfmBackground = Bitmap.getBitmapResource("rounded-border.png");
VerticalFieldManager vfm = new VerticalFieldManager();
vfm.setBorder(BorderFactory.createBitmapBorder(new XYEdges(12,12,12,12),vfmBackground));
BHorizontalFieldManager hfm = new BHorizontalFieldManager();
lblFirstName= new LabelField("First Name :");
hfm.add(lblFirstName);
clblFirstName = new ColoredMultiLineLabelField("Jhon",Color.GRAY);
hfm.add(clblFirstName);
vfm.add(hfm);
vfm.add(new SeparatorField());
BHorizontalFieldManager hfm1 = new BHorizontalFieldManager();
lblLastName= new LabelField("Last Name :");
hfm1.add(lblLastName);
clblLastName = new ColoredMultiLineLabelField("Doe",Color.GRAY);
hfm1.add(clblLastName);
vfm.add(hfm1);
vfm.add(new SeparatorField());
BHorizontalFieldManager hfm2 = new BHorizontalFieldManager();
lblBirthDate = new LabelField("Date Of Birth:");
hfm2.add(lblBirthDate);
clblBirthDate = new ColoredMultiLineLabelField("11-June-1982",Color.GRAY);
hfm2.add(clblBirthDate);
vfm.add(hfm2);
vfm.add(new SeparatorField());
BHorizontalFieldManager hfm3 = new BHorizontalFieldManager();
lblLicenseNumber = new LabelField("License Number :");
hfm3.add(lblLicenseNumber);
clblLicenseNumber = new ColoredMultiLineLabelField("999999",Color.GRAY);
hfm3.add(clblLicenseNumber);
vfm.add(hfm3);
vfm.add(new SeparatorField());
BHorizontalFieldManager hfm4 = new BHorizontalFieldManager();
lblLicenseType = new LabelField("License Type :");
hfm4.add(lblLicenseType);
clblLicenseType = new ColoredMultiLineLabelField("B",Color.GRAY);
hfm4.add(clblLicenseType);
vfm.add(hfm4);
vfm.add(new SeparatorField());
BHorizontalFieldManager hfm5 = new BHorizontalFieldManager();
lblLicenseExpiry = new LabelField("Expiry Date:");
hfm5.add(lblLicenseExpiry);
clblLicenseExpiry = new ColoredMultiLineLabelField("25-Aug-2012",Color.GRAY);
hfm5.add(clblLicenseExpiry);
vfm.add(hfm5);
vfm.add(new SeparatorField());
BHorizontalFieldManager hfm6 = new BHorizontalFieldManager();
lblLicenseStatus = new LabelField("Licenes Status:");
hfm6.add(lblLicenseStatus);
clblLicenseStatus = new ColoredMultiLineLabelField("Expired",Color.GRAY);
hfm6.add(clblLicenseStatus);
vfm.add(hfm6);
vfm.add(new SeparatorField());
add(vfm);
btnLeft = new CustomImageButton(Bitmap.getBitmapResource("left-arrow-enable.png"),Bitmap.getBitmapResource("left-arrow-disable.png"));
btnRight= new CustomImageButton(Bitmap.getBitmapResource("right-arrow-enable.png"),Bitmap.getBitmapResource("right-arrow-disable.png"));;
HorizontalFieldManager arrowButtonHfm = new HorizontalFieldManager(){
public int getPreferredHeight() {
// TODO Auto-generated method stub
return btnLeft.getPreferredHeight()*2;
}
public int getPreferredWidth() {
// TODO Auto-generated method stub
return Display.getWidth();
}
protected void sublayout(int maxWidth, int maxHeight) {
// TODO Auto-generated method stub
int count = getFieldCount();
for(int i = 0 ; i < count ; i++ ){
Field f = getField(i);
if(f == btnLeft ){
setPositionChild(f, (getPreferredWidth() >> 1) - f.getPreferredWidth() - 30, getPreferredHeight()>>1);
}else if (f == btnRight ){
setPositionChild(f, (getPreferredWidth() >> 1) + 30, getPreferredHeight()>>1);
}
layoutChild(f, getPreferredWidth(), getPreferredHeight());
}
setExtent(getPreferredWidth(),getPreferredHeight());
}
public void subpaint(Graphics graphics){
int count = getFieldCount();
for(int i = 0 ; i < count ; i++ ){
net.rim.device.api.ui.Field f = getField(i);
paintChild(graphics,f);
}
}
};
/*add(new LabelField(){
public int getPreferredHeight() {
return 10;
}
});*/
btnLeft.setChangeListener(this);
btnRight.setChangeListener(this);
btnLeft.setEnabled(false);
arrowButtonHfm.add(btnLeft);
arrowButtonHfm.add(btnRight);
add(arrowButtonHfm);
fillLicenseHolderInfoToField((LicenseObject)licenseInfoData.elementAt(currentIndex));
setHeaderText();
enableDisableButtons();
}
private void setHeaderText(){
header.setText("Search Results. ( "+(currentIndex+1)+ " of "+ (licenseInfoData.size())+" )");
}
private void fillLicenseHolderInfoToField(LicenseObject licenseObject){
bmpfDriverPhoto.setImage(licenseObject.getBmpImage());
clblLicenseNumber.setText(licenseObject.getLicenseNum());
clblFirstName.setText(licenseObject.getFirstName());
clblLastName.setText(licenseObject.getLastName());
clblBirthDate.setText(licenseObject.getDateOfBirth());
clblLicenseExpiry.setText(licenseObject.getDateOfExpiry());
clblLicenseType.setText(licenseObject.getLicenseType());
clblLicenseStatus.setText(licenseObject.getLicenseStatus());
}
public void fieldChanged(Field field, int context) {
// TODO Auto-generated method stub
if(field == btnRight){
if( currentIndex < (licenseInfoData.size() - 1)){
currentIndex++;
fillLicenseHolderInfoToField((LicenseObject)licenseInfoData.elementAt(currentIndex));
}
}else if(field == btnLeft){
if( currentIndex > 0 ){
currentIndex--;
fillLicenseHolderInfoToField((LicenseObject)licenseInfoData.elementAt(currentIndex));
}
}else if( field == bmpfDriverPhoto ){
ImagePopDialog dialog = new ImagePopDialog("loader-image-box.png");
Bitmap scaledBitmap = new Bitmap(300, 300);
Bitmap btnBitmap = bmpfDriverPhoto.getImage();
btnBitmap.scaleInto(0, 0, btnBitmap.getWidth(), btnBitmap.getHeight(),
scaledBitmap, 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), 1);
dialog.add(scaledBitmap);
UiApplication.getUiApplication().pushScreen(dialog);
}
enableDisableButtons();
setHeaderText();
}
private void enableDisableButtons(){
btnLeft.setEnabled((currentIndex > 0)?true:false);
btnRight.setEnabled((currentIndex < (licenseInfoData.size() - 1))?true:false);
}
protected boolean onSavePrompt() {
// TODO Auto-generated method stub
return true;
}
}
//自定义图像按钮
package com.app.ui.component;
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.system.Display;
import net.rim.device.api.ui.Color;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.ui.TouchEvent;
/**
* *
* Class to Draw an Image Button
*/
public class CustomImageButton extends Field {
/** Bitmap for enabled image */
private Bitmap bmpEnabled;
/** Bitmap for disabled image */
private Bitmap bmpDisabled;
/** Label for Button*/
private String label;
private boolean mEnabled=true;
private int mCurrentTouchX = 0;
private int mCurrentTouchY = 0;
/**
* Constructor with
* @param image
*/
public CustomImageButton(Bitmap image) {
super(Field.FOCUSABLE);
this.bmpEnabled = image;
}
/**
* Constructor with
* @param enabled
* @param disabled
*/
public CustomImageButton(Bitmap enabled,Bitmap disabled) {
this(enabled);
this.bmpDisabled = disabled;
}
public CustomImageButton(Bitmap enabled, Bitmap disabled, String label) {
this(enabled);
this.bmpDisabled = disabled;
this.label = label;
}
protected void layout(int height, int width) {
height = getPreferredHeight();
width = getPreferredWidth();
setExtent(width,height);
}
protected void paint(Graphics graphics) {
if( isEnabled() ){
if(isFocus()){
int col = graphics.getColor();
graphics.setColor(Color.WHITE);
graphics.fillRect(0, 0, getPreferredHeight(), getPreferredHeight());
graphics.setColor(col);
}
graphics.drawBitmap(5, 5, bmpEnabled.getWidth(), bmpEnabled.getHeight(), bmpEnabled,
0, 0);
if(label != null && !label.equals("")) {
graphics.setColor(Color.BLACK);
graphics.drawText(label, bmpEnabled.getWidth()+5, (getPreferredHeight() - getFont().getHeight())/2);
}
}else{
if( bmpDisabled != null )
graphics.drawBitmap(5, 5, bmpDisabled.getWidth(), bmpDisabled.getHeight(), bmpDisabled,
0, 0);
if(label != null && !label.equals("")) {
graphics.setColor(Color.LIGHTGRAY);
graphics.drawText(label, bmpEnabled.getWidth()+5, (getPreferredHeight() - getFont().getHeight())/2);
}
}
}
public int getPreferredWidth() {
int prefwidth = 0;
if(bmpEnabled != null) {
prefwidth = bmpEnabled.getWidth();
}
if(label != null && !label.equals("")) {
prefwidth = Display.getWidth()+10;
}
return (prefwidth+10);
}
public int getPreferredHeight() {
if(bmpEnabled != null) {
return bmpEnabled.getHeight()+10;
}
return 0;
}
/*protected boolean navigationClick(int status, int time) {
fieldChangeNotify(0);
return true;
}*/
/**
* To set the focused background color and invalidating the entire screen
*/
protected void onFocus(int direction) {
invalidate();
}
/**
* To set the unfocused background color and invalidating the entire screen
*/
protected void onUnfocus() {
invalidate();
}
/**
* Draws the focus indicator for this field.
* @param graphics
* @param on
*/
protected void drawFocus(Graphics graphics, boolean on) {
super.drawFocus(graphics, on);
}
protected boolean navigationClick(int status, int time){
if( mEnabled ){
if (mCurrentTouchX >= 0 && mCurrentTouchX <= getPreferredWidth()
&& mCurrentTouchY >= 0
&& mCurrentTouchY <= getPreferredHeight())
fieldChangeNotify(1);
mCurrentTouchX = 0;
mCurrentTouchY = 0;
return true;
}else{
return false;
}
}
protected boolean touchEvent(TouchEvent message) {
if (mEnabled) {
if (message.getEvent() == TouchEvent.CLICK) {
mCurrentTouchX = message.getX(1);
mCurrentTouchY = message.getY(1);
}
}
return super.touchEvent(message);
}
public void setEnabled(boolean enabled) {
// TODO Auto-generated method stub
super.setEnabled(enabled);
if(!enabled)
this.focusRemove();
}
public void setImage(Bitmap image){
this.bmpEnabled = image;
}
public Bitmap getImage(){
return this.bmpEnabled;
}
}
答案 0 :(得分：0)
在CustomImageButton课程中，您应该更改setImage方法：
public void setImage(Bitmap image){
this.bmpEnabled = image;
}
通过添加无效来导致重绘：
public void setImage(Bitmap image){
this.bmpEnabled = image;
invalidate();
}
问题在于，更换图像后，在刷新屏幕之前，屏幕上不会显示更改。 invalidate()触发刷新屏幕（或布局），允许看到任何更新。
当您滚动或选择图像时，会调用invalidate()方法，以便屏幕刷新，这就是为什么它在此之前不会更新。 invalidate()的手动触发器解决了这个问题。
确保您在事件线程上执行此操作。