Android TextView自动换行文字排版参差不齐的原因
今天项目没什么进展,公司后台出问题了。看了下刚刚学习Android时的笔记,发现TextView会自动换行,而且排版文字参差不齐。查了下资料,总结原因如下:
1、半角字符与全角字符混乱所致:这种情况一般就是汉字与数字、英文字母混用
解决方法一:
将textview中的字符全角化。即将所有的数字、字母及标点全部转为全角字符,使它们与汉字同占两个字节,这样就可以避免由于占位导致的排版混乱问题了。 半角转为全角的代码如下,只需调用即可。
- public static String ToDBC(String input) {
- char[] c = input.toCharArray();
- for (int i = 0; i< c.length; i++) {
- if (c[i] == 12288) {
- c[i] = (char) 32;
- continue;
- }if (c[i]> 65280&& c[i]< 65375)
- c[i] = (char) (c[i] - 65248);
- }
- return new String(c);
- }
解决方法二:
去除特殊字符或将所有中文标号替换为英文标号。利用正则表达式将所有特殊字符过滤,或利用replaceAll()将中文标号替换为英文标号。则转化之后,则可解决排版混乱问题。
- // 替换、过滤特殊字符
- public static String StringFilter(String str) throws PatternSyntaxException{
- str=str.replaceAll("【","[").replaceAll("】","]").replaceAll("!","!");//替换中文标号
- String regEx="[『』]"; // 清除掉特殊字符
- Pattern p = Pattern.compile(regEx);
- Matcher m = p.matcher(str);
- return m.replaceAll("").trim();
- }
2、TextView在显示中文的时候标点符号不能显示在一行的行首和行尾,如果一个标点符号刚好在一行的行尾,该标点符号就会连同前一个字符跳到下一行显示。
解决方法:在标点符号后加一个空格。
3、一个英文单词不能被显示在两行中( TextView在显示英文时,标点符号是可以放在行尾的,但英文单词也不能分开 )。
4、如果要两行对其的显示效果:有两种方法
方法一:
修改Android源代码;将frameworks/base/core/java/android/text下的StaticLayout.java文件中的如下代码:
- if (c == ' ' || c == '/t' ||
- ((c == '.' || c == ',' || c == ':' || c == ';') &&
- (j - 1 < here || !Character.isDigit(chs[j - 1 - start])) &&
- (j + 1 >= next || !Character.isDigit(chs[j + 1 - start]))) ||
- ((c == '/' || c == '-') &&
- (j + 1 >= next || !Character.isDigit(chs[j + 1 - start]))) ||
- (c >= FIRST_CJK && isIdeographic(c, true) &&
- j + 1 < next && isIdeographic(chs[j + 1 - start], false))) {
- okwidth = w;
- ok = j + 1;
- if (fittop < oktop)
- oktop = fittop;
- if (fitascent < okascent)
- okascent = fitascent;
- if (fitdescent > okdescent)
- okdescent = fitdescent;
- if (fitbottom > okbottom)
- okbottom = fitbottom;
- }
去掉就可以了。去掉后标点符号可以显示在行首和行尾,英文单词也可以被分开在两行中显示。
方法二:
自定义View显示文本
网上就有达人采用自定义View来解决这个问题,我做了实验并总结了一下:
自定义View的步骤:
1)继承View类或其子类,例子继承了TextView类;
2)写构造函数,通过XML获取属性(这一步中可以自定义属性,见例程);
3)重写父类的某些函数,一般都是以on开头的函数,例子中重写了onDraw()和onMeasure()函数;
=========================CYTextView.java=============================
- public class CYTextView extends TextView {
- public static int m_iTextHeight; //文本的高度
- public static int m_iTextWidth;//文本的宽度
- private Paint mPaint = null;
- private String string="";
- private float LineSpace = 0;//行间距
- public CYTextView(Context context, AttributeSet set)
- {
- super(context,set);
- TypedArray typedArray = context.obtainStyledAttributes(set, R.styleable.CYTextView);
- int width = typedArray.getInt(R.styleable. CY TextView_textwidth, 320);
- float textsize = typedArray.getDimension(R.styleable. CY TextView_textSize, 24);
- int textcolor = typedArray.getColor(R.styleable. CY TextView_textColor, -1442840576);
- float linespace = typedArray.getDimension(R.styleable. CY TextView_lineSpacingExtra, 15);
- int typeface = typedArray.getColor(R.styleable. CY TextView_typeface, 0);
- typedArray.recycle();
- //设置 CY TextView的宽度和行间距www.linuxidc.com
- m_iTextWidth=width;
- LineSpace=linespace;
- // 构建paint对象
- mPaint = new Paint();
- mPaint.setAntiAlias(true);
- mPaint.setColor(textcolor);
- mPaint.setTextSize(textsize);
- switch(typeface){
- case 0:
- mPaint.setTypeface(Typeface.DEFAULT);
- break;
- case 1:
- mPaint.setTypeface(Typeface.SANS_SERIF);
- break;
- case 2:
- mPaint.setTypeface(Typeface.SERIF);
- break;
- case 3:
- mPaint.setTypeface(Typeface.MONOSPACE);
- break;
- default:
- mPaint.setTypeface(Typeface.DEFAULT);
- break;
- }
- }
- @Override
- protected void onDraw(Canvas canvas)
- {
- super.onDraw(canvas);
- char ch;
- int w = 0;
- int istart = 0;
- int m_iFontHeight;
- int m_iRealLine=0;
- int x=2;
- int y=30;
- Vector m_String=new Vector();
- FontMetrics fm = mPaint.getFontMetrics();
- m_iFontHeight = (int) Math.ceil(fm.descent - fm.top) + (int)LineSpace;//计算字体高度(字体高度+行间距)
- for (int i = 0; i < string.length(); i++)
- {
- ch = string.charAt(i);
- float[] widths = new float[1];
- String srt = String.valueOf(ch);
- mPaint.getTextWidths(srt, widths);
- if (ch == '/n'){
- m_iRealLine++;
- m_String.addElement(string.substring(istart, i));
- istart = i + 1;
- w = 0;
- }else{
- w += (int) (Math.ceil(widths[0]));
- if (w > m_iTextWidth){
- m_iRealLine++;
- m_String.addElement(string.substring(istart, i));
- istart = i;
- i--;
- w = 0;
- }else{
- if (i == (string.length() - 1)){
- m_iRealLine++;
- m_String.addElement(string.substring(istart, string.length()));
- }
- }
- }
- }
- m_iTextHeight=m_iRealLine*m_iFontHeight+2;
- canvas.setViewport(m_iTextWidth, m_iTextWidth);
- for (int i = 0, j = 0; i < m_iRealLine; i++, j++)
- {
- canvas.drawText((String)(m_String.elementAt(i)), x, y+m_iFontHeight * j, mPaint);
- }
- }
- protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
- {
- int measuredHeight = measureHeight(heightMeasureSpec);
- int measuredWidth = measureWidth(widthMeasureSpec);
- this.setMeasuredDimension(measuredWidth, measuredHeight);
- this.setLayoutParams(new LinearLayout.LayoutParams(measuredWidth,measuredHeight));
- super.onMeasure(widthMeasureSpec, heightMeasureSpec);
- }
- private int measureHeight(int measureSpec)
- {
- int specMode = MeasureSpec.getMode(measureSpec);
- int specSize = MeasureSpec.getSize(measureSpec);
- // Default size if no limits are specified.
- initHeight();
- int result = m_iTextHeight;
- if (specMode == MeasureSpec.AT_MOST){
- // Calculate the ideal size of your
- // control within this maximum size.
- // If your control fills the available
- // space return the outer bound.
- result = specSize;
- }else if (specMode == MeasureSpec.EXACTLY){
- // If your control can fit within these bounds return that value.
- result = specSize;
- }
- return result;
- }
- private void initHeight()
- {
- //设置 CY TextView的初始高度为0
- m_iTextHeight=0;
- //大概计算 CY TextView所需高度
- FontMetrics fm = mPaint.getFontMetrics();
- int m_iFontHeight = (int) Math.ceil(fm.descent - fm.top) + (int)LineSpace;
- int line=0;
- int istart=0;
- int w=0;
- for (int i = 0; i < string.length(); i++)
- {
- char ch = string.charAt(i);
- float[] widths = new float[1];
- String srt = String.valueOf(ch);
- mPaint.getTextWidths(srt, widths);
- if (ch == '/n'){
- line++;
- istart = i + 1;
- w = 0;
- }else{
- w += (int) (Math.ceil(widths[0]));
- if (w > m_iTextWidth){
- line++;
- istart = i;
- i--;
- w = 0;
- }else{
- if (i == (string.length() - 1)){
- line++;
- }
- }
- }
- }
- m_iTextHeight=(line)*m_iFontHeight+2;
- }
- private int measureWidth(int measureSpec)
- {
- int specMode = MeasureSpec.getMode(measureSpec);
- int specSize = MeasureSpec.getSize(measureSpec);
- // Default size if no limits are specified.
- int result = 500;
- if (specMode == MeasureSpec.AT_MOST){
- // Calculate the ideal size of your control
- // within this maximum size.
- // If your control fills the available space
- // return the outer bound.
- result = specSize;
- }else if (specMode == MeasureSpec.EXACTLY){
- // If your control can fit within these bounds return that value.
- result = specSize;
- }
- return result;
- }
- public void SetText(String text)(//注:此函数目前只有在UI线程中调用才可以把文本画出来,在其它线程中<p> //无法画文本,找了好久找不到原因,求高手解答)
- {
- string = text;
- // requestLayout();
- // invalidate();
- }
- }</p>
=======================attrs.xml===============================
该文件是自定义的属性,放在工程的res/values下
- <resources>
- <attr name="textwidth" format="integer"/>
- <attr name="typeface">
- <enum name="normal" value="0"/>
- <enum name="sans" value="1"/>
- <enum name="serif" value="2"/>
- <enum name="monospace" value="3"/>
- </attr>
- <declare-styleable name="CYTextView">
- <attr name="textwidth" />
- <attr name="textSize" format="dimension"/>
- <attr name="textColor" format="reference|color"/>
- <attr name="lineSpacingExtra" format="dimension"/>
- <attr name="typeface" />
- </declare-styleable>
- </resources>
=======================main.xml==========================
- <?xml version="1.0" encoding="utf-8"?>
- <ScrollView
- xmlns:Android="http://schemas.android.com/apk/res/android"
- Android:layout_width="320px"
- Android:layout_height="320px"
- Android:background="#ffffffff"
- >
- <LinearLayout
- xmlns:Android="http://schemas.android.com/apk/res/android"
- Android:orientation="vertical"
- Android:layout_width="fill_parent"
- Android:layout_height="fill_parent">
- <com.cy.CYTextView.CYTextView
- xmlns:cy="http://schemas.Android.com/apk/res/ com.cy.CYTextView "
- Android:id="@+id/mv"
- Android:layout_height="wrap_content"
- Android:layout_width="wrap_content"
- cy :textwidth="320"
- cy :textSize="24sp"
- cy :textColor="#aa000000"
- cy :lineSpacingExtra="15sp"
- cy :typeface="serif">
- </com. cy .CYTextView.CYTextView>
- </LinearLayout>
- </ScrollView>
蓝色代码即为自定义View,其中以cy命名空间开头的属性是自定义属性;
=======================Main.java=============================
- public class Main extends Activity {
- CYTextView mCYTextView;
- String text = "Android提供了精巧和有力的组件化模型构建用户的UI部分。主要是基于布局类:View和 ViewGroup。在此基础上,android平台提供了大量的预制的View和xxxViewGroup子类,即布局(layout)和窗口小部件(widget)。可以用它们构建自己的UI。";
- @Override
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- this.setContentView(R.layout.main);
- mCYTextView = (CYTextView)findViewById(R.id.mv);
- mCYTextView.SetText(text);
- }
- }