j2me 低级UI控件之文本域
这阵子忙项目，写了个控件，有点像文本域，显示文章用的，带滚动条，有拖拽事件，不过还是有个小问题不咋完美。我承认我的代码不适合阅读，因为注释比较少，并且这个控件的开发难度有点大，主要是拖拽的地方有点复杂，最重要的是，代码还经过一定的优化，合并了许多变量，不过有兴趣的人也可以挑战一下~
设计思路很简单，滚动条的走动依附文本的走动，根据倍数算出各个变量。
具体的实现我自己都不愿意回忆了。
该代码发布之意在于供人使用，不侧重于供人学习阅读。
package com.ctai.items.textarea;import java.util.Vector;import javax.microedition.lcdui.Font;import javax.microedition.lcdui.Graphics;import com.ctai.utils.ColorSet;import com.ctai.utils.DefaultProperties;public class Textarea{/** 文字颜色 */private int i_c_strColor;/** x, y, 宽, 高*/public int x, y, width, hight;/** 文字整体高度 */private int i_allStrHight;/** 整体高度 */private int i_strHight;private Vector v;/** 倍数 */private int Multiple;/** 滚动条高度 */private int scrollHight;/** 滚动条的X和Y坐标 */private int scrollX, scrollY;/** ↑↓按钮方块固定Y */private int boxY;/** ↑↓按钮方块的宽高 */private int boxWH = 16;/** 方向键滚屏像素值 */private int rollValue;/** 方向键滚屏侧滑块移动的偏差像素值 */private int rollMoveScrollValue;/** 临时变量 */private int temp, temp2, temp3, temp4, temp5, temp6, temp7, temp8;/** 文字是否超过一篇 */private boolean b_isHaveMore = true;private int i_dragged[] = new int;/** * 文本域 * @param st_strOut 文本域内文字 * @param font 当前g的字体 * @param i_c_strColor 文字颜色 * @param x * @param y * @param width 宽 * @param hight 高 * @param rollValue 方向键滚屏像素值 * */public Textarea(String st_strOut, Font font, int i_c_strColor, int x, int y, int width, int hight, int rollValue){this.i_c_strColor = i_c_strColor;this.x = x;this.scrollX = x + width; // 滑块X的坐标初始化this.y = y;this.temp7 = y;this.boxY = y;this.scrollY = y + boxWH; // 滑块Y的坐标初始化this.width = width;this.hight = hight;this.rollValue = rollValue;v = getSubsection(st_strOut, font, width, "\r\n"); // 赋值vectorinit();temp8 = 320 - (boxY + boxWH * 2 + scrollHight + 30);}public void init(){Multiple = (temp6 + ((260 / i_strHight) - 1)) / (260 / i_strHight); //倍数 if (Multiple == 1){b_isHaveMore = false;}else{scrollHight = (hight - boxWH * 2) * 260 / (temp6 * i_strHight);}temp = hight - boxWH;temp2 = (boxWH >> 2);temp3 = scrollX + (boxWH >> 1);temp4 = temp2 * 3;temp5 = boxWH * 2;}public void paint(Graphics g){g.setColor(i_c_strColor);if (v != null && v.size() > 0){for (int i = 0; i < v.size(); i++){g.drawString(v.elementAt(i).toString(), x, i * i_strHight + y, 0);}}// 画整个滚动条g.setColor(ColorSet.scrollBackColor);g.fillRect(scrollX - 1, boxY - 1, boxWH + 2, hight + 2);// 画上、下小箭头块边框g.setColor(ColorSet.scrollBorderColor);g.fillRect(scrollX - 1, boxY - 1, boxWH + 2, boxWH + 2);g.fillRect(scrollX - 1, boxY + temp - 1, boxWH + 2, boxWH + 2);// 画上、下箭头小块g.setColor(ColorSet.scrollFontColor);g.fillRect(scrollX, boxY, boxWH, boxWH);g.fillRect(scrollX, boxY + temp, boxWH, boxWH);// 画箭头g.setColor(ColorSet.scrollIcoColor);// 画∧// 画/g.drawLine(temp3, boxY + temp2, scrollX + temp2, boxY + temp4);// 画\g.drawLine(temp3, boxY + temp2, scrollX + temp4, boxY + temp4);// 画∨// 画\g.drawLine(temp3, boxY + temp + temp4, scrollX + temp2, boxY + temp + temp2);// 画/g.drawLine(temp3, boxY + temp + temp4, scrollX + temp4, boxY + temp + temp2);g.setColor(ColorSet.scrollBorderColor);g.fillRect(scrollX, scrollY + rollMoveScrollValue, boxWH, scrollHight);g.setColor(ColorSet.scrollFontColor);g.fillRect(scrollX + 1, scrollY + rollMoveScrollValue + 1, boxWH - 2, scrollHight - 2);}public void pointerDragged(int x, int y){if(b_isHaveMore){i_dragged = i_dragged;i_dragged = y;if(x < scrollX && y > boxY && y < 290){this.y -= i_dragged - i_dragged;if (this.y - this.temp7 <= i_allStrHight){this.y = i_allStrHight + this.temp7;}else if (this.y >= boxY){this.y = boxY;}rollMoveScrollValue = getXY(temp8, this.y - this.temp7, i_allStrHight);if (rollMoveScrollValue < 0){rollMoveScrollValue = 0;}}if(x > scrollX && x < 239 && y > scrollY + rollMoveScrollValue && y < scrollY + rollMoveScrollValue + scrollHight){this.y += (i_dragged - i_dragged) * (i_allStrHight / (hight - (boxWH * 2) - scrollHight));if (this.y - this.temp7 <= i_allStrHight){this.y = i_allStrHight + this.temp7;}else if (this.y >= boxY){this.y = boxY;}rollMoveScrollValue = getXY(temp8, this.y - this.temp7, i_allStrHight);if (rollMoveScrollValue < 0){rollMoveScrollValue = 0;}}}}public void keyPressed(int keyCode){if (b_isHaveMore){if (keyCode == DefaultProperties.KEY_DOWN){this.y -= rollValue;if (this.y - this.temp7 <= i_allStrHight){this.y = i_allStrHight + this.temp7 + 2;}}if (keyCode == DefaultProperties.KEY_UP){this.y += rollValue;if (this.y >= boxY){this.y = boxY;}}rollMoveScrollValue = getXY(temp8, this.y - this.temp7, i_allStrHight);if (rollMoveScrollValue < 0){rollMoveScrollValue = 0;}}}public void pointerPressed(int x, int y){if (b_isHaveMore){i_dragged = y;i_dragged = y;if (x > scrollX && x < scrollX + boxWH && y > scrollY && y < scrollY + hight - temp5) // 在滑块内点击时间的捕捉{if (y < scrollY + rollMoveScrollValue){this.y += hight;if (this.y >= boxY){this.y = boxY;}} else if (y > scrollY + rollMoveScrollValue + scrollHight){this.y -= hight;if (this.y - this.temp7 <= i_allStrHight){this.y = i_allStrHight + this.temp7 + 2;}}rollMoveScrollValue = getXY(temp8, this.y - this.temp7, i_allStrHight);if (rollMoveScrollValue < 0){rollMoveScrollValue = 0;}}else if (x > scrollX && x < scrollX + boxWH && y > boxY && y < boxY + boxWH){this.y += rollValue;if (this.y >= boxY){this.y = boxY;}rollMoveScrollValue = getXY(temp8, this.y - this.temp7, i_allStrHight);if (rollMoveScrollValue < 0){rollMoveScrollValue = 0;}} else if (x > scrollX && x < scrollX + boxWH && y > boxY + temp && y < boxY + hight){this.y -= rollValue;if (this.y - this.temp7 <= i_allStrHight){this.y = i_allStrHight + this.temp7 + 2;}rollMoveScrollValue = getXY(temp8, this.y - this.temp7, i_allStrHight);}}}private final int getXY(int w, int x, int Exp){return (int) (((long) (x * w) * 1000000) / ((long) Exp * 1000000));}/** 此方法会根据文字内容自动返回长度适应给定width的vector */public Vector getSubsection(String strSource, Font font, int width, String strSplit){Vector vector = new Vector();String temp = strSource;int i, j;int LastLength = 1;int step = 0;try {while (!temp.equals("")){i = temp.indexOf("\n");if (i > 0){if (font.stringWidth(temp.substring(0, i - 1)) >= width){i = -1;}}if (i == -1){if (LastLength > temp.length()){i = temp.length();}else{i = LastLength;step = font.stringWidth(temp.substring(0, i)) > width ? -1 : 1;if (i < temp.length()){while (!(font.stringWidth(temp.substring(0, i)) <= width && font.stringWidth(temp.substring(0, i + 1)) > width)){i = i + step;if (i == temp.length()){break;}}}}if (!strSplit.equals("")){j = i;if (i < temp.length()){while (strSplit.indexOf(temp.substring(i - 1, i)) == -1){i--;if (i == 0){i = j;break;}}}}}LastLength = i;vector.addElement(temp.substring(0, i));if (i == temp.length()){temp = "";}else{temp = temp.substring(i);if (temp.substring(0, 1).equals("\n")){temp = temp.substring(1);}}}}catch (Exception e){System.out.println("getSubsection:" + e);}temp6 = vector.size();i_strHight = font.getHeight();i_allStrHight = 320 - boxY - 30 - vector.size() * i_strHight;return vector;}}
有些颜色的静态变量是另一个颜色管理类的，使用时替换成你想要的颜色即可。
此控件支持的触屏事件：文字域的拖拽，滚动条的拖拽，上下按钮的点击，滚动条底色区域的翻屏事件
此控件支持的按键事件：手机键盘上下按钮文字像素滚动。
附件有这个类的源码。
页:
[1]