黑莓中的图像button

如何在BlackBerry中实现图像button?

    在这里你去完成代码:

    import net.rim.device.api.system.Bitmap; import net.rim.device.api.ui.Graphics; import net.rim.device.api.ui.component.ButtonField; /** * Button field with a bitmap as its label. */ public class BitmapButtonField extends ButtonField { private Bitmap bitmap; private Bitmap bitmapHighlight; private boolean highlighted = false; /** * Instantiates a new bitmap button field. * * @param bitmap the bitmap to use as a label */ public BitmapButtonField(Bitmap bitmap, Bitmap bitmapHighlight) { this(bitmap, bitmapHighlight, ButtonField.CONSUME_CLICK|ButtonField.FIELD_HCENTER|ButtonField.FIELD_VCENTER); } public BitmapButtonField(Bitmap bitmap, Bitmap bitmapHighlight, long style) { super(style); this.bitmap = bitmap; this.bitmapHighlight = bitmapHighlight; } /* (non-Javadoc) * @see net.rim.device.api.ui.component.ButtonField#layout(int, int) */ protected void layout(int width, int height) { setExtent(getPreferredWidth(), getPreferredHeight()); } /* (non-Javadoc) * @see net.rim.device.api.ui.component.ButtonField#getPreferredWidth() */ public int getPreferredWidth() { return bitmap.getWidth(); } /* (non-Javadoc) * @see net.rim.device.api.ui.component.ButtonField#getPreferredHeight() */ public int getPreferredHeight() { return bitmap.getHeight(); } /* (non-Javadoc) * @see net.rim.device.api.ui.component.ButtonField#paint(net.rim.device.api.ui.Graphics) */ protected void paint(Graphics graphics) { super.paint(graphics); int width = bitmap.getWidth(); int height = bitmap.getHeight(); Bitmap b = bitmap; if (highlighted) b = bitmapHighlight; graphics.drawBitmap(0, 0, width, height, b, 0, 0); } public void setHighlight(boolean highlight) { this.highlighted = highlight; } } 

    使用RIM的高级UI包。

    http://supportforums.blackberry.com/t5/Java-Development/Implement-advanced-buttons-fields-and-managers/ta-p/488276

    这包含一个BitmapButton字段和大量有用的UI工具。

    (毫无疑问,Reflogs的例子是好的,但我认为对于登陆这个页面的新的BB开发者来说,高级UI包更有利)

     perfect ImageButton for Blackberry , According to user point of view a Imagebutton should have four states 1. Normal 2. Focus 3. Selected Focus 4. Selected unfocus the Following code maintain all four states (Field-Change-Listener and Navigation) if you want to maintain all four states than use 1st Constructor, If you just want to handle Focus/Un-Focu state of the button than use 2nd one ######################################## import net.rim.device.api.system.Bitmap; import net.rim.device.api.ui.Field; import net.rim.device.api.ui.Graphics; public class ImageButton extends Field { Bitmap mNormalIcon; Bitmap mFocusedIcon; Bitmap mActiveNormalIcon; Bitmap mActiveFocusedIcon; Bitmap mActiveBitmap; String mActiveText; int mHeight; int mWidth; boolean isStateActive = false; boolean isTextActive = false; public boolean isStateActive() { return isStateActive; } public ImageButton(Bitmap normalIcon, Bitmap focusedIcon) { super(Field.FOCUSABLE | FIELD_VCENTER); mNormalIcon = normalIcon; mFocusedIcon = focusedIcon; mActiveBitmap = normalIcon; mActiveFocusedIcon = focusedIcon; mActiveNormalIcon = normalIcon; // isTextActive = false; } public ImageButton(Bitmap normalIcon, Bitmap focusedIcon, Bitmap activeNormalIcon, Bitmap activeFocusedIcon) { super(Field.FOCUSABLE | FIELD_VCENTER); mNormalIcon = normalIcon; mFocusedIcon = focusedIcon; mActiveFocusedIcon = activeFocusedIcon; mActiveNormalIcon = activeNormalIcon; mActiveBitmap = normalIcon; // isTextActive = true; } protected void onFocus(int direction) { if ( !isStateActive ) { mActiveBitmap = mFocusedIcon; } else { mActiveBitmap = mActiveFocusedIcon; } } protected void onUnfocus() { super.onUnfocus(); if ( !isStateActive ) { mActiveBitmap = mNormalIcon; } else { mActiveBitmap = mActiveNormalIcon; } } protected boolean navigationClick(int status, int time) { mActiveBitmap = mActiveNormalIcon; toggleState(); invalidate(); fieldChangeNotify(1); return true; } public void toggleState() { isStateActive = !isStateActive; } public int getPreferredWidth() { return mActiveBitmap.getWidth() + 20; } public int getPreferredHeight() { return mActiveBitmap.getHeight() + 10; } protected void layout(int width, int height) { mWidth = getPreferredWidth(); mHeight = getPreferredHeight(); setExtent(mWidth, mHeight); } protected void paint(Graphics graphics) { graphics.drawBitmap(0, 5, mWidth, mHeight, mActiveBitmap, 0, 0); // graphics.setColor(0xff0000); // graphics.drawText(mActiveText, ( mActiveBitmap.getWidth() - // this.getFont().getAdvance("ON") ) / 2, mActiveBitmap.getHeight()); } protected void drawFocus(Graphics graphics, boolean on) { } public void activate() { mActiveBitmap = mActiveNormalIcon; isStateActive = true; invalidate(); } public void deactivate() { mActiveBitmap = mNormalIcon; isStateActive = false; invalidate(); } } 

    最简单的方法来做到这一点:

    第1步:绘制具有特定坐标的图像(imageX,imageY)。 第2步:在你的代码中添加一个方法:

      void pointerControl(int x, int y) { if (x>imageX && x<imageX+imageName.getWidth() && y>imageY && y < imageY+imageName.getHeight) { //to do code here } } where imageName:name of image imageX=x coordinate of image(Top-Left) imageY=y coordinate of image(Top-Left)