Question

我正在尝试更改焦点上自定义按钮字段的位图。我有2个图像，一个是灰色的，另一个是红色的，我希望在按钮聚焦时交换它们。

此代码使按钮在几分之一秒内从正常值旋转，从灰色变为红色。聚焦后，它会被选中，并产生不需要的事件。更改后，它会回到原来的颜色，模拟器会冻结。

任何人都可以帮我们找到这段代码的错误吗？

我的自定义buttonField类：

import net.rim.device.api.system.Bitmap;
import net.rim.device.api.system.Characters;
import net.rim.device.api.ui.Color;
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.ui.component.BitmapField;

public class ImageNavbarButtonField extends BitmapField{

private Bitmap image;
private boolean isFocused;

public ImageNavbarButtonField(Bitmap image) {
    super(image);
    this.image = image;
}

public boolean isFocusable() {
    return true;
}

protected boolean navigationClick(int status, int time) {
    fieldChangeNotify(0);
    return true;
}

protected boolean trackwheelClick(int status, int time) {
    fieldChangeNotify(0);
    return true;
}

protected void drawFocus(Graphics graphics, boolean on){} 
public void onFocus(){
        setBitmap(ImageResizer.generateHitBitmap(image));
        invalidate();
 }

 public void onUnfocus(){
         //super.onUnfocus();
         setBitmap(image);
         invalidate();
 }

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

protected boolean keyChar(char character, int status, int time) {
    if(Characters.ENTER == character || Characters.SPACE == character) {
        fieldChangeNotify(0);
        return true;
    }
    return super.keyChar(character, status, time);
}

}

Answer 1

试试这个

final imagebutton sav_users = new imagebutton("",Field.FOCUSABLE, "normalimage.png","mouseoverimage.png", 0x9cbe95);

图像按钮类在下面给出 -

import net.rim.device.api.ui.*;
import net.rim.device.api.system.*;

public class imagebutton extends Field {

private String _label;
private int _labelHeight;
private int _labelWidth;
private Font _font;

private Bitmap _currentPicture;
private Bitmap _onPicture; 
private Bitmap _offPicture; 
int color;

public imagebutton(String text, long style ,String img, String img_hvr, int color){
    super(style);


    _offPicture = Bitmap.getBitmapResource(img);
    _onPicture = Bitmap.getBitmapResource(img_hvr);

    _font = getFont();
    _label = text;
    _labelHeight = _onPicture.getHeight();  
    _labelWidth = _onPicture.getWidth();

    this.color = color;

    _currentPicture = _offPicture;
}

/**
 * @return The text on the button
 */
String getText(){
    return _label;
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#getPreferredHeight()
 */
public int getPreferredHeight(){
    return _labelHeight;
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#getPreferredWidth()
 */
public int getPreferredWidth(){
    return _labelWidth;
}

/**
 * Field implementation.  Changes the picture when focus is gained.
 * @see net.rim.device.api.ui.Field#onFocus(int)
 */
protected void onFocus(int direction) {
    _currentPicture = _onPicture;
    invalidate();
}

/**
 * Field implementation.  Changes picture back when focus is lost.
 * @see net.rim.device.api.ui.Field#onUnfocus()
 */
protected void onUnfocus() {
    _currentPicture = _offPicture;
    invalidate();
}

/**
 * Field implementation.  
 * @see net.rim.device.api.ui.Field#drawFocus(Graphics, boolean)
 */
protected void drawFocus(Graphics graphics, boolean on) {
    // Do nothing
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#layout(int, int)
 */
protected void layout(int width, int height) {
    setExtent(Math.min( width, getPreferredWidth()), 
    Math.min( height, getPreferredHeight()));
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#paint(Graphics)
 */
protected void paint(Graphics graphics){       
    // First draw the background colour and picture
    graphics.setColor(this.color);
    graphics.fillRect(0, 0, getWidth(), getHeight());
    graphics.drawBitmap(0, 0, getWidth(), getHeight(), _currentPicture, 0, 0);

    // Then draw the text
    graphics.setColor(Color.BLACK);
    graphics.setFont(_font);
    graphics.drawText(_label, 4, 2, 
        (int)( getStyle() & DrawStyle.ELLIPSIS | DrawStyle.HALIGN_MASK ),
        getWidth() - 6 );
}

/**
 * Overridden so that the Event Dispatch thread can catch this event
 * instead of having it be caught here..
 * @see net.rim.device.api.ui.Field#navigationClick(int, int)
 */
protected boolean navigationClick(int status, int time){
    fieldChangeNotify(1);
    return true;
}

}

Answer 2

您可以像这样创建customButton：

public class ImageNavbarButtonField extends Field{

    protected Bitmap image;
    protected Bitmap inverseImage;
    protected int fieldWidth;
    protected int fieldHeight;

    public ImageNavbarButtonField (Bitmap image,long style) {
        super(Field.FOCUSABLE | style);
        this.image = image;
        this.inverseImage = ImageResizer.generateHitBitmap(image);
        fieldHeight = image.getHeight();
        fieldWidth = image.getWidth();
    }
    public int getPreferredWidth() {
        return fieldWidth;
    }
    public int getPreferredHeight() {
        return fieldHeight;
    }
    protected void paint(Graphics graphics) {
        if (isFocus()){
            graphics.drawBitmap(0,0,fieldWidth,fieldHeight,inverseImage,0,0);
        }else{
            graphics.drawBitmap(0,0,fieldWidth,fieldHeight,image,0,0);
        }
    }
    protected boolean navigationClick(int status, int time) {
        fieldChangeNotify(0);
        return true;
    }

    protected boolean trackwheelClick(int status, int time) {
        fieldChangeNotify(0);
        return true;
    }
    protected boolean keyChar(char character, int status, int time) {
        if(Characters.ENTER == character || Characters.SPACE == character) {
            fieldChangeNotify(0);
            return true;
        }
        return super.keyChar(character, status, time);
    }
}

Answer 3

使用PictureBackgroundButtonField或Buttonfield的{{1}}课程。下面是班级。 `package com.picturebackgroundbuttonfield;

import net.rim.device.api.ui。; import net.rim.device.api.system。;

/ ** *自定义按钮字段，显示如何将图像用作按钮背景。 * / 公共类PictureBackgroundButtonField扩展Field {
private String _label; private int _labelHeight; private int _labelWidth; private Font _font; 私有Bitmap _onPicture，_offPicture; 私有Bitmap _currentPicture;

yourcustom class

} `

以下面的方式使用它..

/**
 * Constructor.
 * @param text The text to be displayed on the button
 * @param style Combination of field style bits to specify display attributes 
 */
public PictureBackgroundButtonField(Bitmap onFocus, Bitmap offFocus, String text, long style) 
{
    super(style);
    _onPicture = onFocus;
    _offPicture = offFocus;
    _font = getFont();
    _label = text;
    _labelHeight = _onPicture.getHeight();
    _labelWidth = _onPicture.getWidth();
    _currentPicture = _offPicture;
}

/**
 * @return The text on the button
 */
String getText()
{
    return _label;
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#getPreferredHeight()
 */
public int getPreferredHeight() 
{
    return _labelHeight;
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#getPreferredWidth()
 */
public int getPreferredWidth() 
{
    return _labelWidth;
}

/**
 * Field implementation.  Changes the picture when focus is gained.
 * @see net.rim.device.api.ui.Field#onFocus(int)
 */
protected void onFocus(int direction) 
{
    _currentPicture = _onPicture;
   // setFont(getFont().derive(Font.BOLD));
    invalidate();
}

/**
 * Field implementation.  Changes picture back when focus is lost.
 * @see net.rim.device.api.ui.Field#onUnfocus()
 */

protected void onUnfocus() 
{
    _currentPicture = _offPicture;
  //  setFont(getFont().derive(Font.PLAIN));
    invalidate();
}

/**
 * Field implementation.  
 * @see net.rim.device.api.ui.Field#drawFocus(Graphics, boolean)
 */
protected void drawFocus(Graphics graphics, boolean on) 
{
    // Do nothing
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#layout(int, int)
 */
protected void layout(int width, int height) 
{
    setExtent(Math.min( width, getPreferredWidth()), 
    Math.min( height, getPreferredHeight()));
}

/**
 * Field implementation.
 * @see net.rim.device.api.ui.Field#paint(Graphics)
 */

/**
 * Overridden so that the Event Dispatch thread can catch this event
 * instead of having it be caught here..
 * @see net.rim.device.api.ui.Field#navigationClick(int, int)
 */
protected boolean navigationClick(int status, int time) 
{
    fieldChangeNotify(1);
    return true;
}

/*protected void paint(Graphics graphics) {
    // TODO Auto-generated method stub

}*/

protected void paint(Graphics graphics) 
{       
    graphics.drawBitmap(0, 0, getWidth(), getHeight(), _currentPicture, 0, 0);
    graphics.setBackgroundColor(Color.BLACK);
    graphics.drawText(_label, 2, 0, 
            (int)( getStyle() & DrawStyle.ELLIPSIS | DrawStyle.HALIGN_MASK ),
            getWidth() - 6 );
}

如何在焦点上更改自定义按钮位图？（黑莓）

3 个答案:

如何在焦点上更改自定义按钮位图？ （黑莓）

3 个答案:

如何在焦点上更改自定义按钮位图？（黑莓）