BlackBerry-自定义大小编辑字段

就像戴夫约翰斯顿说的:

class LikesHFManager extends HorizontalFieldManager {
    EditField mEditFieldLeft;
    LabelField mLabelField;
    EditField mEditFieldRight;
    String STR_LIKES = "likes";
    int mLabelWidth = 0;
    int mEditWidth = 0;
    int mOffset = 4;

    public LikesHFManager() {
        mEditFieldLeft = new EditField();
        mLabelField = new LabelField(STR_LIKES);
        mEditFieldRight = new EditField();

        mLabelWidth = mLabelField.getFont().getAdvance(STR_LIKES);
        int screenWidth = Display.getWidth();
        mEditWidth = (screenWidth - mLabelWidth) >> 1;
        mEditWidth -= 2 * mOffset;

        // calculate max with of one character
        int chMaxWith = mEditFieldLeft.getFont().getAdvance("W");
        // calculate max count of characters in edit field
        int chMaxCnt = mEditWidth / chMaxWith;

        mEditFieldLeft.setMaxSize(chMaxCnt);
        mEditFieldRight.setMaxSize(chMaxCnt);

        add(mEditFieldLeft);
        add(mLabelField);
        add(mEditFieldRight);
    }

    protected void sublayout(int maxWidth, int maxHeight) {

        int x = 0;
        int y = 0;

        int editHeight = mEditFieldLeft.getPreferredHeight();
        int labelHeight = mLabelField.getPreferredHeight();

        setPositionChild(mEditFieldLeft, x, y);
        layoutChild(mEditFieldLeft, mEditWidth, editHeight);
        x += mEditWidth;
        x += mOffset;

        setPositionChild(mLabelField, x, y);
        layoutChild(mLabelField, mLabelWidth, labelHeight);
        x += mLabelWidth;
        x += mOffset;

        setPositionChild(mEditFieldRight, x, y);
        layoutChild(mEditFieldRight, mEditWidth, editHeight);
        x += mEditWidth;

        setExtent(x, Math.max(labelHeight, editHeight));
    }
}

尝试对HorizontalFieldManager进行子类化,并重写子布局方法:

protected void sublayout(int maxWidth, int maxHeight) { }

在这个方法中,您应该为要添加的每个组件调用setPositionChild()和layoutChild(),这样您就可以控制每个组件的位置和大小。

还应重写每个组件的布局方法并调用

setExtent(getPreferredWidth(), getPreferredHeight()); 

这将使用getPreferred的实现…您已经编写的方法。

希望这有帮助。

基于Max Gontar的解决方案,这应该解决水平场管理器子字段宽度分配的一般问题:

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

public class FieldRowManager extends HorizontalFieldManager {
    public FieldRowManager(final long style)
    {
        super(style);
    }
    public FieldRowManager()
    {
        this(0);
    }

    private SubField FirstSubField = null;
    private SubField LastSubField = null;
    private static class SubField
    {
        public final Field Field;
        public final int Width;
        public final int Offset;
        private SubField Next;
        public SubField(final FieldRowManager container, final Field field, final int width, final int offset)
        {
            Field = field;
            Width = width;
            Offset = offset;

            if (container.LastSubField == null)
            {
                container.FirstSubField = this;
            }
            else
            {
                container.LastSubField.Next = this;
            }
            container.LastSubField = this;
        }
        public SubField getNext()
        {
            return Next;
        }
    }

    public void add(final Field field)
    {
        add(field, field.getPreferredWidth());
    }
    public void add(final Field field, final int width)
    {
        add(field, width, 0);
    }
    public void add(final Field field, final int width, final int offset)
    {
        new SubField(this, field, width, offset);
        super.add(field);
    }

    protected void sublayout(final int maxWidth, final int maxHeight)
    {
        int x = 0;
        int height = 0;
        SubField subField = FirstSubField;
        while (subField != null)
        {
            final Field field = subField.Field;
            final int fieldHeight = field.getPreferredHeight();
            this.setPositionChild(field, x, 0);
            this.layoutChild(field, subField.Width, fieldHeight);
            x += subField.Width+subField.Offset;
            if (fieldHeight > height)
            {
                height = fieldHeight;
            }

            subField = subField.getNext();
        }
        this.setExtent(x, height);
    }
}

只需调用add方法的重载来指定宽度和下一个字段之前的偏移空间。但这不允许删除/替换字段。

RIM没有在标准库中提供这种功能,这让人很不舒服。水平场管理器 应该 就这样工作。