对齐2个文本,1个正常,1个相反

Question

我做了一个 安卓 应用程序有一个按钮,其中总共有4个文本,我想对齐第一个2.一个位于底部文本的最左侧,另一个位于底部文本的右侧.

所以从这个:

setText(item.title + " " + item.roomId + "\n" + item.teacher + " " + item.classes);

对此:

setText(declare here a spannable);

我想我应该一起工作Spannable,我已经尝试了一些事情Alignment.ALIGN_NORMAL和Alignment.ALIGN_OPPOSITE,但我认为是应该首先计算底部文本的长度,然后做了比对.(我在这里找到了一个很好的例子,但它在我的设置中没有用).

我希望有人能指出我的方向.

编辑:

我不能(我认为)使用RelativeLayout或是LinearLayout因为我在另一个类(ScheduleItemView.java)中扩展按钮的原因:

/**
 * Custom view that represents a {@link ScheduleItem} instance, including its
 * title and time span that it occupies. Usually organized automatically by
 * {@link ScheduleItemsLayout} to match up against a {@link TimeRulerView}
 * instance.
 */
public class ScheduleItemView extends Button {

    private ScheduleItem mItem;

    public ScheduleItemView(Context context, ScheduleItem item) {
        super(context);

        mItem = item;

        setSingleLine(false);
        setText(item.title + " " + item.roomId + "\n" + item.teacher + " "
                + item.classes);

        // TODO: turn into color state list with layers?
        int textColor = Color.WHITE;
        int accentColor = item.accentColor;

        LayerDrawable buttonDrawable = (LayerDrawable) context.getResources()
                .getDrawable(R.drawable.btn_block);
        buttonDrawable.getDrawable(0).setColorFilter(accentColor,
                PorterDuff.Mode.SRC_ATOP);
        buttonDrawable.getDrawable(1).setAlpha(item.containsStarred ? 255 : 0);

        setTextColor(textColor);
        setTextSize(TypedValue.COMPLEX_UNIT_PX, getResources()
                .getDimensionPixelSize(R.dimen.text_size_small));

        setGravity(Gravity.CENTER | Gravity.BOTTOM);

        setBackgroundDrawable(buttonDrawable);
    }

    public ScheduleItem getScheduleItem() {
        return mItem;
    }

    @Override
    public void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        measure(MeasureSpec.makeMeasureSpec(getMeasuredWidth(),
                MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(
                getMeasuredHeight(), MeasureSpec.EXACTLY));
        // layout(getLeft(), getTop(), getRight(), getBottom());
        setGravity(Gravity.CENTER);

    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        setMeasuredDimension(getRight() - getLeft(), getBottom() - getTop());
    }
}

我试过在protected void onLayout(ScheduleItemsLayout.java)中这样做:

child.setLayoutParams(new LayoutParams(
        LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));

但那不起作用.我不确定我是否应该使用new RelativeLayout(this).

Spannable在这种情况下使用它更好吗？

^{项目源可以在这里下载(你可以在Eclipse中导入)}

Answer 1

好吧，如果您无法从 a 转移Button到 a ViewGroup，那么您可以在扩展 Button 类中执行以下操作：

消除：

setText(item.title + " " + item.roomId + "\n" + item.teacher + " "
            + item.classes);

将以下内容添加到ScheduleItemView's构造函数中：

float[] fl1 = new float[item.title.length()];
getPaint().getTextWidths(item.title, fl1);

float[] fl2 = new float[item.roomId.length()];
getPaint().getTextWidths(item.roomId, fl2);

float[] fl3 = new float[item.teacher.length() + item.classes.length() + 1];
getPaint().getTextWidths(item.teacher + " " + item.classes, fl3);

float differenceInWidth = sumUpTheArray(fl3) 
                          - sumUpTheArray(fl1) 
                          - sumUpTheArray(fl2);

float fSpaceArray[] = new float[1];

getPaint().getTextWidths(" ", fSpaceArray);

int numOfSpaces = (int) (differenceInWidth / fSpaceArray[0]);

char[] spaceCharArr = new char[numOfSpaces];

Arrays.fill(spaceCharArr, ' ');

setText(item.title + String.valueOf(spaceCharArr) + item.roomId + "\n" 
                            + item.teacher + " " + item.classes);

添加这个辅助方法来对数组求和float：

public float sumUpTheArray(float[] arr) {
    float sum = 0f;

    for (int i = 0; i < arr.length; i++) {
        sum += arr[i];
    }

    return sum;
}

不知道为什么你要覆盖onDraw(Canvas)和onMeasure(int, int)方法。

不用说，这是一个复杂的代码片段。title正在发生的事情是，我们正在测量必须在两者之间放置多少空间roomId才能获得所需的对齐方式。该代码很简单（尽管令人畏缩），因此没有包含任何注释。

另一方面，您可以扩展RelativeLayout：

public class ScheduleItemAlternateView extends RelativeLayout {

    private ScheduleItem mItem;  

    public ScheduleItemAlternateView(Context context, ScheduleItem item) {
        super(context);

        mItem = item;

        int textColor = Color.WHITE;
        int accentColor = item.accentColor;

        LayerDrawable buttonDrawable = (LayerDrawable) context.getResources()
            .getDrawable(R.drawable.btn_block);
        buttonDrawable.getDrawable(0).setColorFilter(accentColor,
            PorterDuff.Mode.SRC_ATOP);
        buttonDrawable.getDrawable(1).setAlpha(item.containsStarred ? 255 : 0);

        // Three TextViews to hold the `title`, `roomId`
        // and `teacher&room` independently
        TextView tvTitle = new TextView(context);
        TextView tvRoomId = new TextView(context);
        TextView tvTeacherAndClasses = new TextView(context);

        // Example ids
        tvTitle.setId(100);
        tvRoomId.setId(101);
        tvTeacherAndClasses.setId(102);

        tvTitle.setTextSize(TypedValue.COMPLEX_UNIT_PX, getResources()
            .getDimensionPixelSize(R.dimen.text_size_small));
        tvRoomId.setTextSize(TypedValue.COMPLEX_UNIT_PX, getResources()
            .getDimensionPixelSize(R.dimen.text_size_small));
        tvTeacherAndClasses.setTextSize(TypedValue.COMPLEX_UNIT_PX, getResources()
            .getDimensionPixelSize(R.dimen.text_size_small));

        tvTitle.setPadding(30, 20, 30, 0);
        tvRoomId.setPadding(30, 20, 30, 0);
        tvTeacherAndClasses.setPadding(30, 5, 30, 20);

        tvTitle.setTextColor(textColor);
        tvRoomId.setTextColor(textColor);
        tvTeacherAndClasses.setTextColor(textColor);

        // Set text
        tvTitle.setText(item.title);        
        tvRoomId.setText(item.roomId);      
        tvTeacherAndClasses.setText(item.teacher + " " + item.classes);

        // LayoutParms
        RelativeLayout.LayoutParams paramsTitle = 
                                 new RelativeLayout.LayoutParams(
                                     RelativeLayout.LayoutParams.WRAP_CONTENT,
                                     RelativeLayout.LayoutParams.WRAP_CONTENT);

        paramsTitle.addRule(RelativeLayout.ALIGN_LEFT, 
                                                  tvTeacherAndClasses.getId());

        RelativeLayout.LayoutParams paramsRoomId = 
                                 new RelativeLayout.LayoutParams(
                                     RelativeLayout.LayoutParams.WRAP_CONTENT,
                                     RelativeLayout.LayoutParams.WRAP_CONTENT);

        paramsRoomId.addRule(RelativeLayout.ALIGN_RIGHT, 
                                                  tvTeacherAndClasses.getId());

        RelativeLayout.LayoutParams paramsTeacherAndClasses = 
                                 new RelativeLayout.LayoutParams(
                                     RelativeLayout.LayoutParams.WRAP_CONTENT,
                                     RelativeLayout.LayoutParams.WRAP_CONTENT);

        paramsTeacherAndClasses.addRule(RelativeLayout.CENTER_HORIZONTAL);
        paramsTeacherAndClasses.addRule(RelativeLayout.BELOW, tvTitle.getId());

        // Add Views to this RelativeLayout
        addView(tvTitle, paramsTitle);
        addView(tvRoomId, paramsRoomId);
        addView(tvTeacherAndClasses, paramsTeacherAndClasses);

        // Set the background as LayerDrawable
        setBackgroundDrawable(buttonDrawable);          
    }
}

在这里，我们创建三个 TextView，并设置它们的 LayoutParams 以获得正确的对齐方式。

两者的输出是相同的，但我建议第二种方法：