Android TextView自動換行文字排版參差不齊的原因
轉:http://niufc.iteye.com/blog/1729792
今天專案沒什麼進展,公司後臺出問題了。看了下剛剛學習Android時的筆記,發現TextView會自動換行,而且排版文字參差不齊。查了下資料,總結原因如下:
1、半形字元與全形字元混亂所致:這種情況一般就是漢字與數字、英文字母混用
解決方法一:
將textview中的字元全形化。即將所有的數字、字母及標點全部轉為全形字元,使它們與漢字同佔兩個位元組,這樣就可以避免由於佔位導致的排版混亂問題了。 半形轉為全形的程式碼如下,只需呼叫即可。
Java程式碼-
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);
- }
解決方法二:
去除特殊字元或將所有中文標號替換為英文標號。利用正則表示式將所有特殊字元過濾,或利用replaceAll()將中文標號替換為英文標號。則轉化之後,則可解決排版混亂問題。
Java程式碼- // 替換、過濾特殊字元
- public static String StringFilter(String str) throws PatternSyntaxException{
- str=str.replaceAll("【","[").replaceAll("】","]").replaceAll("!","!");//替換中文標號
-
String regEx="[『』]"; // 清除掉特殊字元
- Pattern p = Pattern.compile(regEx);
- Matcher m = p.matcher(str);
- return m.replaceAll("").trim();
- }
2、TextView在顯示中文的時候標點符號不能顯示在一行的行首和行尾,如果一個標點符號剛好在一行的行尾,該標點符號就會連同前一個字元跳到下一行顯示。
解決方法:在標點符號後加一個空格。
3、一個英文單詞不能被顯示在兩行中( TextView在顯示英文時,標點符號是可以放在行尾的,但英文單詞也不能分開 )。
4、如果要兩行對其的顯示效果:有兩種方法
方法一:
修改Android原始碼;將frameworks/base/core/java/android/text下的StaticLayout.java檔案中的如下程式碼:
Java程式碼- 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。去掉後標點符號可以顯示在行首和行尾,英文單詞也可以被分開在兩行中顯示。
方法二:
自定義View顯示文字
網上就有達人採用自定義View來解決這個問題,我做了實驗並總結了一下:
自定義View的步驟:
1)繼承View類或其子類,例子繼承了TextView類;
2)寫建構函式,通過XML獲取屬性(這一步中可以自定義屬性,見例程);
3)重寫父類的某些函式,一般都是以on開頭的函式,例子中重寫了onDraw()和onMeasure()函式;
=========================CYTextView.java=============================
Java程式碼- public class CYTextView extends TextView {
- public static int m_iTextHeight; //文字的高度
- public static int m_iTextWidth;//文字的寬度
- private Paint mPaint = null;
- private String string="";
- private float LineSpace = 0;//行間距
- 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();
- //設定 CY TextView的寬度和行間距www.linuxidc.com
- m_iTextWidth=width;
- LineSpace=linespace;
- // 構建paint物件
- 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;//計算字型高度(字型高度+行間距)
- 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()
- {
- //設定 CY TextView的初始高度為0
- m_iTextHeight=0;
- //大概計算 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, w