Android开发之自定义view实现通讯录列表A~Z字母提示效果【附demo源码下载】

本文实例讲述了android开发之自定义view实现通讯录列表a~z字母提示效果。分享给大家供大家参考，具体如下：

开发工具：eclipse

运行环境：htc g9 android2.3.3

话不多说，先看效果图

其实左右边的a~z是一个自定义的view，它直接覆盖在listview上。

myletterlistview：

public class myletterlistview extends view {
  ontouchingletterchangedlistener ontouchingletterchangedlistener;
  string[] b = {"#","a","b","c","d","e","f","g","h","i","j","k","l"
      ,"m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
  int choose = -1;
  paint paint = new paint();
  boolean showbkg = false;
  public myletterlistview(context context, attributeset attrs, int defstyle) {
    super(context, attrs, defstyle);
  }
  public myletterlistview(context context, attributeset attrs) {
    super(context, attrs);
  }
  public myletterlistview(context context) {
    super(context);
  }
  @override
  protected void ondraw(canvas canvas) {
    super.ondraw(canvas);
    if(showbkg){
      canvas.drawcolor(color.parsecolor("#40000000"));
    }
    int height = getheight();
    int width = getwidth();
    int singleheight = height / b.length;
    for(int i=0;i<b.length;i++){
      paint.setcolor(color.white);
      paint.settypeface(typeface.default_bold);
      paint.setantialias(true);
      if(i == choose){
        paint.setcolor(color.parsecolor("#3399ff"));
        paint.setfakeboldtext(true);
      }
      float xpos = width/2 - paint.measuretext(b[i])/2;
      float ypos = singleheight * i + singleheight;
      canvas.drawtext(b[i], xpos, ypos, paint);
      paint.reset();
    }
  }
  @override
  public boolean dispatchtouchevent(motionevent event) {
    final int action = event.getaction();
    final float y = event.gety();
    final int oldchoose = choose;
    final ontouchingletterchangedlistener listener = ontouchingletterchangedlistener;
    final int c = (int) (y/getheight()*b.length);
    switch (action) {
      case motionevent.action_down:
        showbkg = true;
        if(oldchoose != c && listener != null){
          if(c > 0 && c< b.length){
            listener.ontouchingletterchanged(b[c]);
            choose = c;
            invalidate();
          }
        }
        break;
      case motionevent.action_move:
        if(oldchoose != c && listener != null){
          if(c > 0 && c< b.length){
            listener.ontouchingletterchanged(b[c]);
            choose = c;
            invalidate();
          }
        }
        break;
      case motionevent.action_up:
        showbkg = false;
        choose = -1;
        invalidate();
        break;
    }
    return true;
  }
  @override
  public boolean ontouchevent(motionevent event) {
    return super.ontouchevent(event);
  }
  public void setontouchingletterchangedlistener(
      ontouchingletterchangedlistener ontouchingletterchangedlistener) {
    this.ontouchingletterchangedlistener = ontouchingletterchangedlistener;
  }
  public interface ontouchingletterchangedlistener{
    public void ontouchingletterchanged(string s);
  }
}

然后我在activity中ontouchingletterchangedlistener中监听手指触摸到了哪个字母，然后让列表跳转到对应的位置，

弹出首字母提示框：

private class letterlistviewlistener implements ontouchingletterchangedlistener{
    @override
    public void ontouchingletterchanged(final string s) {
      if(alphaindexer.get(s) != null) {
        int position = alphaindexer.get(s);
        personlist.setselection(position);
        overlay.settext(sections[position]);
        overlay.setvisibility(view.visible);
        handler.removecallbacks(overlaythread);
        //延迟一点五秒后执行，让overlay为不可见
        handler.postdelayed(overlaythread, 1500);
      }
    }
}

延迟一秒让弹出的首字母提示框变为不可见，也就是那个首字母提示框只会显示一秒钟的时间：

//设置overlay不可见
private class overlaythread implements runnable {
    @override
    public void run() {
      overlay.setvisibility(view.gone);
    }
}

还有关于解析汉子的首字母拼音的问题，我这里是查的系统数据库，里面正好有sort_key这一列，比如名字是张三，那么他对应的sort_key就是：zhang张san三，这样一来就容易多了：

//获得汉语拼音首字母
private string getalpha(string str) {
    if (str == null) {
      return "#";
    }
    if (str.trim().length() == 0) {
      return "#";
    }
    char c = str.trim().substring(0, 1).charat(0);
    // 正则表达式，判断首字母是否是英文字母
    pattern pattern = pattern.compile("^[a-za-z]+{1}quot;);
    if (pattern.matcher(c + "").matches()) {
      return (c + "").touppercase();
    } else {
      return "#";
    }
}

如果你的数据不是从联系人表中查的，那可以使用第三方jar包，就是pinyin4j-2.5.0。

activity代码和布局文件比较长，我就不在这里贴了。

附：demo源码点击此处本站下载。

更多关于android相关内容感兴趣的读者可查看本站专题：《android开发入门与进阶教程》、《android布局layout技巧总结》、《android视图view技巧总结》、《android编程之activity操作技巧总结》、《android操作json格式数据技巧总结》、《android资源操作技巧汇总》及《android控件用法总结》

希望本文所述对大家android程序设计有所帮助。