android 畫文字自動換行

[email protected] 2011-11-16

展開全文

package com.dcs.tools;

import java.util.Vector;

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.FontMetrics;
import android.view.KeyEvent;

public class TextUtil {

   private float mTextPosx = 0;// x坐標
   private float mTextPosy = 0;// y坐標
   private float mTextWidth = 0;// 繪制寬度
   private float mTextHeight = 0;// 繪制高度
   private int mFontHeight = 0;// 繪制字體高度
   private int mPageLineNum = 0;// 每一頁顯示的行數(shù)
   private int mCanvasBGColor = 0;// 背景顏色
   private int mFontColor = 0;// 字體顏色
   private int mAlpha = 0;// Alpha值
   private int mRealLine = 0;// 字符串真實的行數(shù)
   private int mCurrentLine = 0;// 當前行
   private int mTextSize = 0;// 字體大小
   private String mStrText = "";
   private Vector mString = null;
   private Paint mPaint = null;

   public TextUtil(String StrText, float x, float y, float w, float h, int bgcolor,
           int textcolor, int alpha, int textsize) {
       mPaint = new Paint();
       mString = new Vector();
       this.mStrText = StrText;
       this.mTextPosx = x;
       this.mTextPosy = y;
       this.mTextWidth = w;
       this.mTextHeight = h;
       this.mCanvasBGColor = bgcolor;
       this.mFontColor = textcolor;
       this.mAlpha = alpha;
       this.mTextSize = textsize;
   }

   public void InitText() {
       mString.clear();// 清空Vector
       // 對畫筆屬性的設置
       // mPaint.setARGB(this.mAlpha, Color.red(this.mFontColor), Color
       // .green(this.mFontColor), Color.blue(this.mFontColor));
       mPaint.setTextSize(this.mTextSize);
       mPaint.setColor(Color.BLUE);
       mPaint.setAntiAlias(true);

       this.GetTextIfon();
   }

   /**
   * 得到字符串信息包括行數(shù),，頁數(shù)等信息
   */
   public void GetTextIfon() {
       char ch;
       int w = 0;
       int istart = 0;
       FontMetrics fm = mPaint.getFontMetrics();// 得到系統(tǒng)默認字體屬性
       mFontHeight = (int) (Math.ceil(fm.descent - fm.top) + 2);// 獲得字體高度
       mPageLineNum = (int) (mTextHeight / mFontHeight);// 獲得行數(shù)

       int count = this.mStrText.length();
       for (int i = 0; i < count; i++) {
           ch = this.mStrText.charAt(i);
           float[] widths = new float[1];
           String str = String.valueOf(ch);
           mPaint.getTextWidths(str, widths);
           if (ch == '/n') {
               mRealLine++;// 真實的行數(shù)加一
               mString.addElement(this.mStrText.substring(istart, i));
               istart = i + 1;
               w = 0;
           } else {
               w += (int) Math.ceil(widths[0]);
               if (w > this.mTextWidth) {
                   mRealLine++;// 真實的行數(shù)加一
                   mString.addElement(this.mStrText.substring(istart, i));
                   istart = i;
                   i--;
                   w = 0;
               } else {
                   if (i == count - 1) {
                       mRealLine++;// 真實的行數(shù)加一
                       mString.addElement(this.mStrText.substring(istart,
                               count));
                   }
               }
           }
       }
   }

   /**
   * 繪制字符串
   *
   * @param canvas
   */
   public void DrawText(Canvas canvas) {
        for (int i = this.mCurrentLine, j = 0; i < this.mRealLine; i++, j++) {
           if (j > this.mPageLineNum) {
               break;
           }
           canvas.drawText((String) (mString.elementAt(i)), this.mTextPosx,
                   this.mTextPosy + this.mFontHeight * j, mPaint);
       }
   }

   /**
   * 翻頁等按鍵處理
   *
   * @param keyCode
   * @param event
   * @return
   */
   public boolean KeyDown(int keyCode, KeyEvent event) {
       if (keyCode == KeyEvent.KEYCODE_DPAD_UP) {
           if (this.mCurrentLine > 0) {
               this.mCurrentLine--;
           }
       } else if (keyCode == KeyEvent.KEYCODE_DPAD_DOWN) {
           if ((this.mCurrentLine + this.mPageLineNum) < (this.mRealLine - 1)) {
               this.mCurrentLine++;
           }
       }
       return false;
   }
}