Question

我正在尝试组合一个看起来像这样的对话框：

填写以下字段
_______________喜欢____________________

其中“_”行是EditFields。

我将所有字段都放在HorizontalFieldManager中，我将其添加到对话框中。不幸的是，第一个EditField占用了第一行的所有空间。我试图通过创建我自己的扩展BasicEditField的类来覆盖EditField的getPreferredWidth（）方法，但是没有成功。

当然必须有一种简单的方法来强制编辑字段的特定大小。我错过了什么？

Answer 1

就像DaveJohnston说的那样：

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));
    }
}

Answer 2

尝试继承HorizontalFieldManager并覆盖子布局方法：

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

在此方法中，您应为要添加的每个组件调用setPositionChild（）和layoutChild（），以便控制每个组件的位置和大小。

您还应该覆盖每个组件的布局方法并调用

setExtent(getPreferredWidth(), getPreferredHeight());

这将使用您已经编写的getPreferred ...方法的实现。

希望这有帮助。

Answer 3

在Max Gontar的解决方案的基础上，这应解决将宽度分配给HorizontalFieldManagers的子字段的一般问题：

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，并指定下一个Field之前的偏移空间。虽然这不允许删除/替换字段。

RIM不在标准库中提供此功能，这很令人讨厌。 HorizontalFieldManager 应以这种方式工作。

黑莓 - 自定义大小EditField

3 个答案: