我是黑莓开发的新手,我甚至不知道如何开始。我已经从它的官方网站上阅读了部分内容
和其他如此多的链接,但我不能发布所有的链接,因为它说,如果你想发布更多的链接,那么你必须有10个声誉,我没有那么抱歉,
现在我的问题是我想设计像http://postimg.org/image/we3leycsd/
这样的布局我如何设计这种布局呢?我正在使用eclipse进行黑莓开发。
请帮助我已经尝试了很多东西,但我无法做到这一点。
您的任何帮助将不胜感激。提前谢谢。
答案 0 :(得分:2)
我会在里面创建一个包含n HorizontalFieldManager
的自定义VerticalFieldManager
,然后覆盖add
和delete
方法。这是我之前做过的,应该适合你,它将新字段添加到最短的列。
StaggeredListView.java:
public class StaggeredListView extends HorizontalFieldManager
{
private int column_spacing = 0;
public StaggeredListView(int columns)
{
super(VERTICAL_SCROLL | VERTICAL_SCROLLBAR | NO_HORIZONTAL_SCROLL | NO_HORIZONTAL_SCROLLBAR | USE_ALL_WIDTH);
if (columns < 1)
{
throw new RuntimeException("Number of columns needs to be larger than 0.");
}
final int width = Display.getWidth() / columns;
for (int i = 0; i < columns; i++)
{
VerticalFieldManager vfm = new VerticalFieldManager(NO_VERTICAL_SCROLL | NO_VERTICAL_SCROLLBAR | NO_HORIZONTAL_SCROLL | NO_HORIZONTAL_SCROLLBAR)
{
protected void sublayout(int maxWidth, int maxHeight)
{
maxWidth = Math.min(width, getPreferredWidth());
maxHeight = Math.min(maxHeight, getPreferredHeight());
super.sublayout(width, maxHeight);
super.setExtent(width, maxHeight);
}
};
super.add(vfm);
}
}
public int getColumnCount()
{
return getFieldCount();
}
/**
* Sets the spacing between columns.
*
* <p>
* Spacing between fields is <i><b>not</b></i> set.
* </p>
*/
public void setColumnSpacing(int spacing)
{
if (spacing < 0) throw new RuntimeException("Column spacing my not be negative.");
int length = getColumnCount();
for (int i = 1; i < length; i++)
{
((VerticalFieldManager) getField(i)).setPadding(0, 0, 0, spacing);
}
column_spacing = spacing;
}
/**
* Get the value currently assigned via the {@link #setColumnSpacing(int)} method.
*
* @return
*/
public int getColumnSpacing()
{
return column_spacing;
}
/**
* Deletes all fields from each of the columns.
*/
public void clear()
{
int length = getColumnCount();
for (int i = 0; i < length; i++)
{
((VerticalFieldManager) getField(i)).deleteAll();
}
}
/**
* Delete specified field from the columns.
*
* <p>
* Does <b><i>not</i></b> rearrange fields.
* </p>
*/
public void delete(Field field)
{
int length = getColumnCount();
for (int i = 0; i < length; i++)
{
try
{
((VerticalFieldManager) getField(i)).delete(field);
break;
} catch (IllegalArgumentException e)
{
// field not in this manager
}
}
}
/**
* Adds the field to the column with the least height.
*/
public void add(Field field)
{
// find the vfm with least height
int index = 0;
int height = ((VerticalFieldManager) getField(index)).getPreferredHeight();
int length = getColumnCount();
for (int i = 1; i < length; i++)
{
int temp_height = ((VerticalFieldManager) getField(i)).getPreferredHeight();
if (temp_height < height)
{
height = temp_height;
index = i;
}
}
((VerticalFieldManager) getField(index)).add(field);
}
}
至于包含在其中的项目,我会创建一个带有图像和文本的字段,然后自己绘制它(我有很多焦点问题,并且发现使用绘画更容易)。
您可以使用它来制作BaseButton
http://developer.blackberry.com/bbos/java/documentation/tutorial_create_custom_button_1969896_11.html
BaseButton.java:
public abstract class BaseButton extends Field
{
// flags to indicate the current visual state
protected boolean _visible = true;
protected boolean _active;
protected boolean _focus;
protected boolean drawfocus = false;
private int touch_top = 0;
private int touch_right = 0;
private int touch_bottom = 0;
private int touch_left = 0;
protected boolean fire_on_click = true; // false fires on unclick
public BaseButton()
{
this(0);
}
public BaseButton(long style)
{
super((style & Field.NON_FOCUSABLE) == Field.NON_FOCUSABLE ? style : style | Field.FOCUSABLE);
}
/**
* Sets the radius around the button to trigger touch events.
* <p>
* (0,0,0,0) by default.
* </p>
*/
public void setTouchRadius(int top, int right, int bottom, int left)
{
touch_top = top;
touch_right = right;
touch_bottom = bottom;
touch_left = left;
}
protected void onFocus(int direction)
{
_focus = true;
invalidate();
super.onFocus(direction);
}
protected void onUnfocus()
{
if (_active || _focus)
{
_focus = false;
_active = false;
invalidate();
}
super.onUnfocus();
}
public void set_visible(boolean visible)
{
_visible = visible;
invalidate();
}
public boolean is_visible()
{
return _visible;
}
protected void drawFocus(Graphics g, boolean on)
{
if (drawfocus) super.drawFocus(g, on);
}
protected void layout(int width, int height)
{
setExtent(Math.min(width, getPreferredWidth()), Math.min(height, getPreferredHeight()));
}
protected boolean keyUp(int keycode, int time)
{
if (Keypad.map(Keypad.key(keycode), Keypad.status(keycode)) == Characters.ENTER)
{
_active = false;
invalidate();
return true;
}
return false;
}
protected boolean keyDown(int keycode, int time)
{
if (Keypad.map(Keypad.key(keycode), Keypad.status(keycode)) == Characters.ENTER)
{
_active = true;
invalidate();
}
return super.keyDown(keycode, time);
}
protected boolean keyChar(char character, int status, int time)
{
if (character == Characters.ENTER)
{
clickButton();
return true;
}
return super.keyChar(character, status, time);
}
protected boolean navigationClick(int status, int time)
{
if (status != 0)
{ // non-touch event
_active = true;
invalidate();
if (fire_on_click) clickButton();
}
return true;
}
protected boolean trackwheelClick(int status, int time)
{
if (status != 0)
{ // non-touch event
_active = true;
invalidate();
if (fire_on_click) clickButton();
}
return true;
}
protected boolean navigationUnclick(int status, int time)
{
if (status != 0)
{ // non-touch event
_active = false;
invalidate();
if (!fire_on_click) clickButton();
}
return true;
}
protected boolean trackwheelUnclick(int status, int time)
{
if (status != 0)
{ // non-touch event
_active = false;
invalidate();
if (!fire_on_click) clickButton();
}
return true;
}
protected boolean invokeAction(int action)
{
switch (action)
{
case ACTION_INVOKE :
{
clickButton();
return true;
}
}
return super.invokeAction(action);
}
protected boolean touchEvent(TouchEvent message)
{
boolean isOutOfBounds = touchEventOutOfBounds(message);
switch (message.getEvent())
{
case TouchEvent.CLICK :
if (!_active)
{
_active = true;
invalidate();
}
if (!isOutOfBounds)
{
if (fire_on_click) clickButton();
return true;
}
case TouchEvent.DOWN :
if (!isOutOfBounds)
{
if (!_active)
{
_active = true;
invalidate();
}
return true;
}
return false;
case TouchEvent.UNCLICK :
if (_active)
{
_active = false;
invalidate();
}
if (!isOutOfBounds)
{
if (!fire_on_click) clickButton();
return true;
}
case TouchEvent.UP :
if (_active)
{
_active = false;
invalidate();
}
default :
return false;
}
}
private boolean touchEventOutOfBounds(TouchEvent message)
{
int x = message.getX(1);
int y = message.getY(1);
return (x < 0 - touch_left || y < 0 - touch_top || x > getWidth() + touch_right || y > getHeight() + touch_bottom);
}
public void setDirty(boolean dirty)
{
}
public void setMuddy(boolean muddy)
{
}
public void clickButton()
{
if (_visible) fieldChangeNotify(0);
}
}
ImageSubtitleButton.java:
public class ImageSubtitleButton extends BaseButton
{
private static final int FOCUS_THINKNESS = 2;
String title;
Bitmap image_default;
int height;
public ImageSubtitleButton(String title, String image_default)
{
this.image_default = Bitmap.getBitmapResource(image_default);
setTitle(title);
}
public void setTitle(String title)
{
this.title = title;
height = image_default.getHeight() + getFont().getHeight() + (FOCUS_THINKNESS * 2);
updateLayout();
invalidate();
}
public int getPreferredWidth()
{
return Math.max(getFont().getAdvance(title), image_default.getWidth());
}
public int getPreferredHeight()
{
return height;
}
protected void paint(Graphics graphics)
{
int x = (getWidth() - image_default.getWidth()) / 2;
int y = 0;
graphics.drawBitmap(x, y, image_default.getWidth(), image_default.getHeight(), image_default, 0, 0);
if (_focus)
{
graphics.setColor(Color.BLUE); // your focus colour
for (int i = 0; i < FOCUS_THINKNESS; i++)
{
graphics.drawRect(x + i, y + i, image_default.getWidth() - (i * 2), image_default.getHeight() - (i * 2));
}
}
graphics.setColor(Color.BLACK);
y = image_default.getHeight();
graphics.drawText(title, x, y);
}
}
现在您可以按如下方式将这些内容添加到屏幕中:
StaggedListView listview = new StaggedListView(2);
ImageSubtitleButton button = new ImageSubtitleButton("test", "test.png");
listview.add(button);
add(listview);
您需要设置ImageSubtitleButton
的首选宽度和高度,以使其保持一致,就像您发布的示例图片一样。
答案 1 :(得分:1)
道歉,我没有时间创建完整的答案,但我个人不会使用HFM / VFM组合来做到这一点。而是使用一个提供网格的管理器。如果您使用的是足够晚的操作系统,则可以使用GridFieldManager执行此操作,
但我与该经理有过不同的经历。所以我通常使用这个经理:
我希望这能帮到你。