A vertical TextView like Chinese old text style

TextViewVertical.java

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Paint.Align;
import android.graphics.Paint.FontMetrics;
import android.graphics.Typeface;
import android.graphics.drawable.BitmapDrawable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;

public class TextViewVertical extends View {

    private Paint paint;
    private int mTextPosx = 0;// x坐标
    private int mTextPosy = 0;// y坐标
    private int mTextWidth = 0;// 绘制宽度
    private int mFontHeight = 0;// 绘制字体高度
    private float mFontSize = 24;// 字体大小
    private int mRealLine = 0;// 字符串真实的行数
    private int mLineWidth = 0;//列宽度
    private int TextLength = 0;//字符串长度
    private int MaxHeight = 500;
    private String text = "";//待显示的文字
    private Matrix matrix;
    private Align textStartAlign = Align.RIGHT;//draw start left or right.//default right
    BitmapDrawable drawable = (BitmapDrawable) getBackground();

    public TextViewVertical(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public TextViewVertical(Context context, AttributeSet attrs) {
        super(context, attrs);
        matrix = new Matrix();
        paint = new Paint();//新建画笔
        paint.setTextAlign(Align.CENTER);//文字居中
        paint.setAntiAlias(true);//平滑处理
        paint.setColor(Color.BLACK);//默认文字颜色
        try {
            mFontSize = Float.parseFloat(attrs.getAttributeValue(null, "textSize"));//获取字体大小属性
        } catch (Exception e) {
        }
    }

    //设置文字
    public final void setText(String text) {
        this.text = text;
        this.TextLength = text.length();
    }

    //设置字体大小
    public final void setTextSize(float size) {
        if (size != paint.getTextSize()) {
            mFontSize = size;
        }
    }

    //设置字体颜色
    public final void setTextColor(int color) {
        paint.setColor(color);
    }

    //设置字体颜色
    public final void setTextARGB(int a, int r, int g, int b) {
        paint.setARGB(a, r, g, b);
    }

    //设置字体
    public void setTypeface(Typeface tf) {
        if (this.paint.getTypeface() != tf) {
            this.paint.setTypeface(tf);
        }
    }

    //设置行宽
    public void setLineWidth(int LineWidth) {
        mLineWidth = LineWidth;
    }

    //获取实际宽度
    public int getTextWidth() {
        return mTextWidth;
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        Log.v("TextViewVertical", "onDraw");
        if (drawable != null) {
            //画背景
            Bitmap b = Bitmap.createBitmap(drawable.getBitmap(), 0, 0, mTextWidth, MaxHeight);
            canvas.drawBitmap(b, matrix, paint);
        }
        //画字
        draw(canvas, this.text);
    }

    private void draw(Canvas canvas, String thetext) {
        char ch;
        mTextPosy = 0;//初始化y坐标
        mTextPosx = textStartAlign == Align.LEFT ? mLineWidth : mTextWidth - mLineWidth;//初始化x坐标
        for (int i = 0; i < this.TextLength; i++) {
            ch = thetext.charAt(i);
            if (ch == '\n') {
                if (textStartAlign == Align.LEFT) {
                    mTextPosx += mLineWidth;// 换列
                } else {
                    mTextPosx -= mLineWidth;// 换列
                }
                mTextPosy = 0;
            } else {
                mTextPosy += mFontHeight;
                if (mTextPosy > this.MaxHeight) {
                    if (textStartAlign == Align.LEFT) {
                        mTextPosx += mLineWidth;// 换列
                    } else {
                        mTextPosx -= mLineWidth;// 换列
                    }
                    i--;
                    mTextPosy = 0;
                } else {
                    canvas.drawText(String.valueOf(ch), mTextPosx, mTextPosy, paint);
                }
            }
        }

        //调用接口方法
        //activity.getHandler().sendEmptyMessage(TestFontActivity.UPDATE);
    }

    //计算文字行数和总宽
    private void GetTextInfo(int heightMeasureSpec) {
        Log.v("TextViewVertical", "GetTextInfo");
        char ch;
        int h = 0;
        paint.setTextSize(mFontSize);
        //获得字宽
        if (mLineWidth == 0) {
            float[] widths = new float[1];
            paint.getTextWidths("正", widths);//获取单个汉字的宽度
            mLineWidth = (int) Math.ceil(widths[0] * 1.1 + 2);
        }

        FontMetrics fm = paint.getFontMetrics();
        mFontHeight = (int) (Math.ceil(fm.descent - fm.top) * 0.9);// 获得字体高度

        String[] split = text.split("\n");
        int maxTextLength = 0;
        for (String aSplit : split) {
            int length = aSplit.length();
            if (length > maxTextLength) {
                maxTextLength = length;
            }
        }

        int measureHeight = MeasureSpec.getSize(heightMeasureSpec);
        if (measureHeight > 0) {
            int fontHeight = maxTextLength * mFontHeight;
            if (fontHeight > measureHeight) {
                MaxHeight = measureHeight;
            } else {
                MaxHeight = fontHeight;
            }
        }

        //计算文字行数
        mRealLine = 0;
        for (int i = 0; i < this.TextLength; i++) {
            ch = this.text.charAt(i);
            if (ch == '\n') {
                mRealLine++;// 真实的行数加一
                h = 0;
            } else {
                h += mFontHeight;
                if (h > (MaxHeight > 0 ? MaxHeight : 500)) {
                    mRealLine++;// 真实的行数加一
                    i--;
                    h = 0;
                } else {
                    if (i == this.TextLength - 1) {
                        mRealLine++;// 真实的行数加一
                    }
                }
            }
        }

        mRealLine++;//额外增加一行
        mTextWidth = mLineWidth * mRealLine;//计算文字总宽度
        measure(mTextWidth, MaxHeight);//重新调整大小
        layout(getLeft(), getTop(), getLeft() + mTextWidth, getTop() + MaxHeight);//重新绘制容器
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        Log.v("宽高", mTextWidth + ":" + MaxHeight);
        if (mTextWidth == 0 || MaxHeight == 0) {
            GetTextInfo(heightMeasureSpec);
        }
        setMeasuredDimension(mTextWidth, MaxHeight);
    }
}