我有一个HorizontalFieldManager,里面有两个按钮。按钮需要分别放在屏幕的最左侧和最右侧。我知道HorizontalFieldManager只是从左到右放置它们,所以我必须扩展它们。
这是我所做的,但它没有结果。按钮执行会出现,但是太小而且没有文字(我已经设置了)。
这是我的布局代码。
protected void sublayout(int width, int height) {
setPositionChild(getField(0), 0, 0);
int fieldZeroWidth = Max(getField(0).getContentWidth(),getField(0).getPreferredWidth());
int fieldZeroHeight = Max(getField(0).getContentHeight(),getField(0).getPreferredHeight());
layoutChild(getField(0),
fieldZeroWidth,
fieldZeroHeight);
int fieldOneWidth = Max(getField(1).getContentWidth(),getField(1).getPreferredWidth());
setPositionChild(getField(1),
Display.getWidth() - fieldOneWidth,
0);
int fieldOneHeight = Max(getField(1).getPreferredHeight(),getField(1).getContentHeight());
layoutChild(getField(1),
fieldOneWidth,
fieldOneHeight
);
setExtent(Display.getWidth(), Max(getPreferredHeight(),fieldOneHeight,fieldZeroHeight));
}
创建此自定义管理器后,我使用setStatus()函数在底部添加它。
我希望两个按钮出现在相对的两侧(他们这样做),但是尺寸正确,并显示文字。
由于 显然,Max函数在参数之间返回最大值。
答案 0 :(得分:4)
如果您想将两个字段放在Horizontal FieldManager的角落,请使用以下代码:
import net.rim.device.api.ui.*;
/**
* Custom class to place the Fields on two corners of the screen Horizontally
*/
public class JustifiedHorizontalFieldManager extends Manager
{
private static final int SYSTEM_STYLE_SHIFT = 32;
public Field _leftField;
public Field _rightField;
private boolean _giveLeftFieldPriority;
public JustifiedHorizontalFieldManager( Field leftField, Field rightField, boolean giveLeftFieldPriority )
{
this( leftField, rightField, giveLeftFieldPriority, Field.USE_ALL_WIDTH );
}
public JustifiedHorizontalFieldManager( Field leftField, Field rightField, boolean giveLeftFieldPriority, long style )
{
super( style );
_leftField = leftField;
_rightField = rightField;
add( _leftField );
add( _rightField );
_giveLeftFieldPriority = giveLeftFieldPriority;
}
public JustifiedHorizontalFieldManager( boolean giveLeftFieldPriority, long style )
{
super( style );
_giveLeftFieldPriority = giveLeftFieldPriority;
}
public void addLeftField( Field field )
{
if( _leftField != null ) {
throw new IllegalStateException();
}
_leftField = field;
add( _leftField );
}
public void addRightField( Field field )
{
if( _rightField != null ) {
throw new IllegalStateException();
}
_rightField = field;
add( _rightField );
}
public int getPreferredWidth()
{
return _leftField.getPreferredWidth() + _rightField.getPreferredWidth();
}
public int getPreferredHeight()
{
return Math.max( _leftField.getPreferredHeight(), _rightField.getPreferredHeight() );
}
protected void sublayout( int width, int height )
{
Field firstField;
Field secondField;
if( _giveLeftFieldPriority ) {
firstField = _leftField;
secondField = _rightField;
} else {
firstField = _rightField;
secondField = _leftField;
}
int maxHeight = 0;
int availableWidth = width;
availableWidth -= _leftField.getMarginLeft();
availableWidth -= Math.max( _leftField.getMarginRight(), _rightField.getMarginLeft() );
availableWidth -= _rightField.getMarginRight();
layoutChild( firstField, availableWidth, height - firstField.getMarginTop() - firstField.getMarginBottom() );
maxHeight = Math.max( maxHeight, firstField.getMarginTop() + firstField.getHeight() + firstField.getMarginBottom() );
availableWidth -= firstField.getWidth();
layoutChild( secondField, availableWidth, height - secondField.getMarginTop() - secondField.getMarginBottom() );
maxHeight = Math.max( maxHeight, secondField.getMarginTop() + secondField.getHeight() + secondField.getMarginBottom() );
availableWidth -= secondField.getWidth();
if( !isStyle( Field.USE_ALL_HEIGHT ) ) {
height = maxHeight;
}
if( !isStyle( Field.USE_ALL_WIDTH ) ) {
width -= availableWidth;
}
setPositionChild( _leftField, _leftField.getMarginLeft(), getFieldY( _leftField, height ) );
setPositionChild( _rightField, width - _rightField.getWidth() - _rightField.getMarginRight(), getFieldY( _rightField, height ) );
setExtent( width, height );
}
private int getFieldY( Field field, int height )
{
switch( (int)( ( field.getStyle() & FIELD_VALIGN_MASK ) >> SYSTEM_STYLE_SHIFT ) ) {
case (int)( FIELD_BOTTOM >> SYSTEM_STYLE_SHIFT ):
return height - field.getHeight() - field.getMarginBottom();
case (int)( FIELD_VCENTER >> SYSTEM_STYLE_SHIFT ):
return field.getMarginTop() + ( height - field.getMarginTop() - field.getHeight() - field.getMarginBottom() ) / 2;
default:
return field.getMarginTop();
}
}
public Field getLeftField()
{
return _leftField;
}
public Field getRightField()
{
return _rightField;
}
public void replace( Field oldField, Field newField )
{
if( oldField == newField ) {
// Nothing to do
return;
}
if( oldField == _leftField ) {
_leftField = newField;
} else if( oldField == _rightField ) {
_rightField = newField;
}
add( newField );
delete( oldField );
}
}
答案 1 :(得分:1)
如果你想设置文本对齐,那么你必须为buttonfield&设置填充。如果要将对齐设置为buttonfield,则为buttonfield设置边距