自定义TextView实现竖排文本_textview竖排

最近有竖排文本的需求，整理了一些实现方式，最终自定义TextView绘制文本方式满足需求。

参考文档：

https://blog.csdn.net/Blue_Tong/article/details/123376013

英文纵向显示-竖版TextView_windroid之父的博客-CSDN博客

1.设置 android:ems="1" 属性即可

<TextView
    android:text="我的应用"
    android:textSize="32sp"
    android:ems="1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

效果：显示中文

显示英文：

 

特点：

• 实现简单
• 无需自定义view
• 英文不满足需求

2.自定义 TextView 继承 android TextView， 用画笔绘制

 
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Path;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.widget.TextView;
 
 
public class VerticalTextView2 extends TextView {
 
    private final static String TAG = "VerticalTextView2 ";
 
    protected int mTextColor = 0xFFFF0000;
    private String mText;
    private Paint mPaint;
    private Rect mBound;//绘制时控制文本绘制的范围
    private Path path;
 
    public VerticalTextView2(Context context) {
        super(context);
        init();
    }
 
    public VerticalTextView2(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }
 
    public VerticalTextView2(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }
 
    private void init() {
        mPaint = new Paint();//创建画笔
        mText = "我 的 应 用";// 初始化文本
        mPaint.setColor(mTextColor);//初始化画笔颜色
        mPaint.setAntiAlias(true);
        mPaint.setTextSize(32);//初始化文字大小
        mBound = new Rect();//显示区域
        mPaint.getTextBounds(mText, 0, mText.length(), mBound);
        mPaint.clearShadowLayer();
        initDisplay();
        path = new Path();
        path.lineTo(0, 500);
    }
 
    protected void initDisplay() {
        setTypeface(Typeface.SERIF);//风格设置
    }
 
    public boolean isChinese(char str) {
        Character.UnicodeBlock ub = Character.UnicodeBlock.of(str);
        if (ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS
                || ub == Character.UnicodeBlock.CJK_COMPATIBILITY_IDEOGRAPHS
                || ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS_EXTENSION_A
                || ub == Character.UnicodeBlock.GENERAL_PUNCTUATION
                || ub == Character.UnicodeBlock.CJK_SYMBOLS_AND_PUNCTUATION
                || ub == Character.UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS) {
            return true;
        }
        return false;
    }
 
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        float a = mPaint.measureText("正正", 0, 1);
        float left = getWidth() / 2 - a / 2;
        float w;
        final int len = mText.length();
        float py = 0;
        for (int i = 0; i < len; i++) {
            char c = mText.charAt(i);
            w = mPaint.measureText(mText, i, i + 1);//获取字符宽度
 
            StringBuffer b = new StringBuffer();
            b.append(c);
            if (py > getHeight()) {//定义字的范围
                return;
            }
            if (isChinese(c)) {
                py += w;
                if (py > getHeight()) {
                    return;
                }
                canvas.drawText(b.toString(), left, py, mPaint); //中文处理方法
            } else {
                canvas.drawTextOnPath(b.toString(), path, py, -left - 2, mPaint);//其他文字处理方法
                py += w;
            }
        }
    }
}

xml中使用：

java中已经设置了文本，xml中就不再设置文本，否则会显示两个文本，也可以写到自定义属性中

<com.example.myapplication.VerticalTextView2
        android:id="@+id/vertical_text_2"
        android:textSize="32dp" />

效果：显示中文

 显示英文：

特点：

• 支持中文和英文
• 需要自定义TextView
• 必须指定宽和高
• 代码多
• android5.0 之前文字间距不可控

3.直接旋转TextView

实现：
 

package com.example.myapplication;
 
import android.content.Context;
import android.graphics.Canvas;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;
import android.widget.TextView;
 
 
public class VerticalTextView1 extends TextView {
 
    private static final String TAG = "VerticalTextView1";
    final boolean topDown;
 
    public VerticalTextView1(Context context, AttributeSet attrs) {
        super(context, attrs);
        final int gravity = getGravity();
        if (Gravity.isVertical(gravity) && (gravity & Gravity.VERTICAL_GRAVITY_MASK) == Gravity.BOTTOM) {
            setGravity((gravity & Gravity.HORIZONTAL_GRAVITY_MASK) | Gravity.TOP);
            topDown = false;
        } else
            topDown = true;
        setEllipsize(TextUtils.TruncateAt.MARQUEE);
        setMarqueeRepeatLimit(-1);
        setFocusable(true);
        setFocusableInTouchMode(true);
        setSingleLine();
        setScrollBarStyle(View.SCROLLBARS_OUTSIDE_OVERLAY);
    }
 
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(heightMeasureSpec, widthMeasureSpec);
        setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
    }
 
    @Override
    protected boolean setFrame(int l, int t, int r, int b) {
        return super.setFrame(l, t, l + (b - t), t + (r - l));
    }
 
    @Override
    public void onDraw(Canvas canvas) {
        if (topDown) {
            canvas.translate(getHeight(), 0);
            canvas.rotate(90);
        } else {
            canvas.translate(0, getWidth());
            canvas.rotate(-90);
        }
        canvas.clipRect(0, 0, getWidth(), getHeight(), android.graphics.Region.Op.REPLACE);
        super.onDraw(canvas);
    }
}

效果：显示中文：

显示英文：

特点：

• 中文文字会一起旋转
• 支持英文
• 无需自定义属性