如何在android中的指定矩形中绘制文本？

有没有一种方法可以在指定的矩形中绘制文本？
我正在使用直接绘制到画布(ImageView)

canvas.drawText(text,x,y,paint) 

但这将整个文本放在一行中.我想用指定的(x,y),(x1,y1)限制包装文本.我不想使用textviews或任何其他视图.

我只想在图像上绘制文本.

有什么方法可以做到这一点？

提前致谢

解决方法:

首先,您必须确定文本大小.每个字符的宽度可以通过getTextWidths()获得,高度与文本大小相同.尝试估计初始文本大小,然后使用文本的高度和宽度调整最终值.

其次,您需要换行. Paint.getTextWidths()或Paint.breakText()都可以实现此目标.

编辑：添加代码示例.

public static class RectTextView extends View {
    private int mWidth = 200;
    private int mHeight = 100;
    private String mText = "Hello world. Don't you know why, why you and I.";
    private Paint mPaint;
    private List<Integer> mTextBreakPoints;

    public RectTextView(Context context) {
        this(context, null);
    }

    public RectTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mPaint = new Paint();
        mPaint.setColor(Color.WHITE);
        mPaint.setAntiAlias(true);
        setSuitableTextSize();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        setMeasuredDimension(mWidth, mHeight);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        int start = 0;
        int x = 0;
        int y = 0;
        for (int point : mTextBreakPoints) {
            y += mPaint.getTextSize();
            canvas.drawText(mText, start, point, x, y, mPaint);
            start = point;
        }
    }

    private void setSuitableTextSize() {
        int textSize = getEstimateTextSize();
        for (; textSize > 0; textSize--) {
            if (isTextSizeSuitable(textSize))
                return;
        }
    }

    private boolean isTextSizeSuitable(int size) {
        mTextBreakPoints = new ArrayList<Integer>();
        mPaint.setTextSize(size);
        int start = 0;
        int end = mText.length();
        while (start < end) {
            int len = mPaint.breakText(mText, start, end, true, mWidth,
                    null);
            start += len;
            mTextBreakPoints.add(start);
        }
        return mTextBreakPoints.size() * size < mHeight;
    }

    private int getEstimateTextSize() {
        return (int) Math.sqrt(mWidth * mHeight / mText.length() * 2);
    }
}

标签：drawtext,android-canvas,android
来源： https://codeday.me/bug/20191031/1976890.html