Android开发实现自定义水平滚动的容器示例

本文实例讲述了android开发实现自定义水平滚动的容器。分享给大家供大家参考，具体如下：

public class horizontalscrollview extends viewgroup {
  //手势
  private gesturedetector mgesturedetector;
  private horizontalscroller mscroller;
  private int curid;
  //快速滑动
  private boolean isflying;
  //--回调函数-------------------------------------
  private onchangelistener mlistener;
  public void setonchangelistener(onchangelistener listener) {
    if (listener != null) {
      mlistener = listener;
    }
  }
  public interface onchangelistener{
    void move2dest(int curid);
  }
  public horizontalscrollview(context context) {
    this(context, null);
  }
  public horizontalscrollview(context context, attributeset attrs) {
    this(context, attrs, 0);
  }
  public horizontalscrollview(context context, attributeset attrs, int defstyle) {
    super(context, attrs, defstyle);
    mscroller = new horizontalscroller();
    isflying = false;
    initgesture(context);
  }
  @override
  protected void onlayout(boolean changed, int l, int t, int r, int b) {
    // 模向移动，
    for (int i = 0; i < getchildcount(); i++) {
      view view = getchildat(i);
      //给水平方向的每个view定位
      view.layout(i * getwidth(), 0, getwidth() + i * getwidth(), getheight());
    }
  }
  @override
  protected void onmeasure(int widthmeasurespec, int heightmeasurespec) {
    for (int i = 0; i < getchildcount(); i++) {
      view view = getchildat(i);
      view.measure(widthmeasurespec, heightmeasurespec);
    }
    super.onmeasure(widthmeasurespec, heightmeasurespec);
  }
  @override
  public boolean ontouchevent(motionevent event) {
    mgesturedetector.ontouchevent(event);
    switch (event.getaction()) {
    case motionevent.action_down:
      if (!isflying) {
        move2dest();
      }
      isflying = false;
      break;
    case motionevent.action_move:
      break;
    case motionevent.action_up:
      break;
    default:
      break;
    }
    return true;
  }
  public void move2dest() {
    //
    int destid = (getscrollx() + getwidth() / 2) / getwidth();
    move2dest(destid);
  }
  public void move2dest(int destid) {
    curid = destid;
    if (destid > getchildcount() - 1) {
      destid = getchildcount() - 1;
    }
    if (mlistener != null) {
      mlistener.move2dest(curid);
    }
    int distance = (int) (destid * getwidth() - getscrollx());
    // scrollby(distance, 0);
    mscroller.startscroll(getscrollx(), getscrolly(), distance, 0);
    invalidate();
  }
  /**
   * invalidate()此方法会触发下面的方法
   */
  @override
  public void computescroll() {
    // 如果存在偏移，就不断刷新
    if (mscroller.computescrolloffset()) {
      scrollto(mscroller.getcurrx(), 0);
      invalidate();
    }
    super.computescroll();
  }
  private void initgesture(context context) {
    mgesturedetector = new gesturedetector(context, new ongesturelistener() {
      @override
      public boolean onsingletapup(motionevent e) {
        return false;
      }
      @override
      public void onshowpress(motionevent e) {
      }
      @override
      public boolean onscroll(motionevent e1, motionevent e2, float distancex, float distancey) {
        scrollby((int) distancex, 0);
        return false;
      }
      @override
      public void onlongpress(motionevent e) {
      }
      @override
      /**
       * 快速滑动时
       */
      public boolean onfling(motionevent e1, motionevent e2, float velocityx, float velocityy) {
        isflying = true;
        if (curid > 0 && velocityx > 0) {// 表示向左移
          move2dest(curid - 1);
        } else if (curid < getchildcount() && velocityx < 0) {
          move2dest(curid + 1);// 向右
        } else {
          move2dest();// 移到原位
        }
        return false;
      }
      @override
      public boolean ondown(motionevent e) {
        return false;
      }
    });
  }
}

/**
 * 位移计算工具类
 *
 * @author chenlin
 *
 */
public class horizontalscroller {
  private int startx;
  private int starty;
  private int distancex;
  private int distancey;
  private int currentx;
  private int currenty;
  private long starttime;
  private long duration = 1000l;
  private boolean isfinish;
  /**
   *
   * @param scrollx
   *      x坐标
   * @param scrolly
   *      y坐标
   * @param distancex
   *      x方向移动的距离
   * @param distancey
   *      y方向移动的距离
   */
  public void startscroll(int scrollx, int scrolly, int distancex, int distancey) {
    startx = scrollx;
    starty = scrolly;
    this.distancex = distancex;
    this.distancey = distancey;
    isfinish = false;
    starttime = systemclock.uptimemillis();
  }
  /**
   * 计算偏移量，
   *
   * @return true 还在移动 false：移动已经停止
   */
  public boolean computescrolloffset() {
    if (isfinish) {
      return false;
    }
    long timepassed = systemclock.uptimemillis() - starttime;
    if (timepassed < duration) {
      currentx = (int) (startx + distancex * timepassed / duration);
      currenty = (int) (starty + distancey * timepassed / duration);
      system.out.println("currentx:::" + currentx);
    } else if (timepassed >= duration) {
      currentx = startx + distancex;
      currenty = starty + distancey;
      isfinish = true;
    }
    return true;
  }
  public int getcurrx() {
    return currentx;
  }
  public void setcurrentx(int currentx) {
    this.currentx = currentx;
  }
  public int getcurrenty() {
    return currenty;
  }
  public void setcurrenty(int currenty) {
    this.currenty = currenty;
  }
}

使用方法

public class scrollactivity extends activity implements oncheckedchangelistener, onchangelistener {
  private int[] ids = { r.drawable.a1, r.drawable.a2, r.drawable.a3, r.drawable.a4, r.drawable.a5, r.drawable.a6 };
  private horizontalscrollview mview;
  private linearlayout mlayout;
  private radiogroup mgroup;
  @override
  protected void oncreate(bundle savedinstancestate) {
    requestwindowfeature(window.feature_no_title);
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_myscrollview);
    init();
  }
  private void init() {
    mlayout = (linearlayout) findviewbyid(r.id.body_layout);
    mgroup = (radiogroup) findviewbyid(r.id.radiogroup);
    mview = new horizontalscrollview(this);
    for (int i = 0; i < ids.length; i++) {
      imageview imageview = new imageview(this);
      imageview.setbackgroundresource(ids[i]);
      mview.addview(imageview);
    }
    mlayout.addview(mview);
    // 随便添加一个view
    view view = getlayoutinflater().inflate(r.layout.activity_progressview, null);
    mview.addview(view, 3);
    for (int i = 0; i < mview.getchildcount(); i++) {
      radiobutton radiobutton = new radiobutton(this);
      // 设置id的编号
      radiobutton.setid(i);
      mgroup.setorientation(linearlayout.horizontal);
      mgroup.addview(radiobutton);
      if (i == 0) {
        radiobutton.setchecked(true);
      }
    }
    mgroup.setoncheckedchangelistener(this);
    mview.setonchangelistener(this);
  }
  @override
  public void oncheckedchanged(radiogroup group, int checkedid) {
    mview.move2dest(checkedid);
  }
  @override
  public void move2dest(int curid) {
    radiobutton radiobutton = (radiobutton) mgroup.getchildat(curid);
    radiobutton.setchecked(true);
  }
}

布局文件

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical" >
  <radiogroup
    android:id="@+id/radiogroup"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" >
  </radiogroup>
  <linearlayout
    android:id="@+id/body_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
  </linearlayout>
</linearlayout>

更多关于android相关内容感兴趣的读者可查看本站专题：《android基本组件用法总结》、《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。