我想移动an app从使用KeywordFilterField到ListField,我挣扎了几个小时才发现,为什么drawListRow()被调用不同ÿ值 - 这取决于这两个ListField的使用:黑莓:为什么drawListRow()调用不同的y为ListField和KeywordFilterField
如果getRowHeight()返回40,则ÿ值将是 -
对于KeywordFilterField是:0; 40; 80; 120; ...(即按预期)
但是对于列表字段我看到:9; 49; 89; 129; ...(即由于某种原因偏移)
9从哪里来? ListField或ListFieldCallback中是否有方法可以调用以获取此值?我只是试图在列表项之间画一条浅灰色的线。
下面是我的测试代码和border.png(用作BasicEditField边界)被附接:
package mypackage;
import java.util.*;
import net.rim.device.api.collection.*;
import net.rim.device.api.collection.util.*;
import net.rim.device.api.system.*;
import net.rim.device.api.ui.*;
import net.rim.device.api.ui.component.*;
import net.rim.device.api.ui.container.*;
import net.rim.device.api.ui.decor.*;
import net.rim.device.api.util.*;
public class MyList extends UiApplication {
public static void main(String args[]) {
MyList app = new MyList();
app.enterEventDispatcher();
}
public MyList() {
pushScreen(new MyScreen());
}
}
class MyScreen extends MainScreen {
static final int EXTRA_ROWS = 2;
MyItemList myItems = new MyItemList();
ListField myList = new ListField(EXTRA_ROWS);
Border myBorder = BorderFactory.createBitmapBorder(
new XYEdges(12, 12, 12, 12),
Bitmap.getBitmapResource("border.png"));
Background myBg = BackgroundFactory.createSolidBackground(0x111111);
StringProvider myProvider = new StringProvider("Search");
BasicEditField myFind = new BasicEditField(USE_ALL_WIDTH) {
protected void paint(Graphics g) {
if (getTextLength() == 0) {
g.setColor(Color.LIGHTGRAY);
g.drawText(myProvider.toString(), 0, 0);
}
g.setColor(Color.BLACK);
super.paint(g);
}
};
public MyScreen() {
getMainManager().setBackground(myBg);
myFind.setBorder(myBorder);
setTitle(myFind);
myItems.doAdd(new MyItem(1, "Eins"));
myItems.doAdd(new MyItem(2, "Zwei"));
myItems.doAdd(new MyItem(3, "Drei"));
myItems.doAdd(new MyItem(4, "Vier"));
myList.setCallback(new MyListFieldCallback());
add(myList);
}
private class MyListFieldCallback implements ListFieldCallback {
public void drawListRow(ListField list, Graphics g, int index, int y, int width) {
System.err.println("XXX index=" + index+ ", y=" + y + ", width=" + width);
g.setColor(Color.WHITE);
if (index < EXTRA_ROWS) {
Font i = getFont().derive(Font.ITALIC);
g.setFont(i);
g.drawText("Add Item", 0, y);
return;
}
if (index >= EXTRA_ROWS) {
MyItem item = (MyItem) myItems.getAt(index - EXTRA_ROWS);
g.drawText(item.toString(), 0, y);
g.setColor(0x333333);
// XXX why do I need to subtract 9 here?
g.drawLine(0, y-9, width, y-9);
return;
}
g.drawText(list.getEmptyString(), 0, y);
}
public Object get(ListField list, int index) {
return myItems.getAt(index);
}
public int getPreferredWidth(ListField list) {
return Display.getWidth();
}
public int indexOfList(ListField list, String prefix, int start) {
return 0;
}
}
class MyItemList extends SortedReadableList {
public MyItemList() {
super(new MyItem.MyComparator());
}
protected void doAdd(Object obj) {
super.doAdd(obj);
myList.setSize(size() + EXTRA_ROWS);
}
protected boolean doRemove(Object obj) {
myList.setSize(size() - 1 + EXTRA_ROWS);
return super.doRemove(obj);
}
}
}
class MyItem {
int _num;
String _name;
public MyItem(int num, String name) {
_num = num;
_name = name;
}
public String toString() {
return _num + ": " + _name;
}
static class MyComparator implements Comparator {
public int compare(Object obj1, Object obj2) {
MyItem item1 = (MyItem) obj1;
MyItem item2 = (MyItem) obj2;
return item1.toString().compareTo(item2.toString());
}
}
static class MyProvider implements KeywordProvider {
public String[] getKeywords(Object obj) {
MyItem item = (MyItem) obj;
return new String[]{ Integer.toString(item._num), item._name };
}
}
}
所产生的输出是:
[ 64,890] XXX index=0, y=9, width=360
[ 64,890] XXX index=1, y=49, width=360
[ 64,898] XXX index=2, y=89, width=360
[ 64,898] XXX index=3, y=129, width=360
[ 64,906] XXX index=4, y=169, width=360
[ 64,906] XXX index=5, y=209, width=360
更新在代表LY到jprofitt
当我尝试你的建议(我用红色为您的文本和线条):
if (index >= EXTRA_ROWS) {
MyItem item = (MyItem) myItems.getAt(index - EXTRA_ROWS);
g.drawText(item.toString(), 0, y);
g.setColor(Color.RED);
g.drawText("XXX", 0, y + (list.getRowHeight() - list.getFont().getHeight())/2);
g.setColor(0x333333);
// XXX why do I need to subtract 9 here?
g.drawLine(0, y-9, width, y-9);
g.setColor(Color.RED);
g.drawLine(0, y, width, y);
return;
}
然后它并没有真正的工作 - 因为蓝色重点线不对齐的建议(红色)线。它对齐与我(灰)线,这意味着你真的需要减去-9出于某种原因:
谢谢! 亚历克斯
也许检查是否有某些填充由于某种原因被添加。我过去观察过这种行为,我想说填充或边距是问题。 – jprofitt 2011-05-17 14:34:06
我同意,但哪种方法会打印该填充?我不想将9硬编码到我的应用程序中。 – 2011-05-17 14:38:53
我会检查列表和包含管理器getPaddingTop/Bottom()和getMarginTop/Bottom() – jprofitt 2011-05-17 15:39:31