Android自定义viewgroup 使用adapter适配数据（6）

package com.example.libingyuan.horizontallistview.ScrollViewGroup;import android.content.Context;import android.util.AttributeSet;import android.util.DisplayMetrics;import android.util.Log;import android.view.GestureDetector;import android.view.MotionEvent;import android.view.View;import android.view.ViewGroup;import android.view.WindowManager;import android.widget.BaseAdapter;import android.widget.GridView;import android.widget.Scroller;/** * 自定义ViewGroup（横向滚动） */public class ScrollViewGroup extends ViewGroup {  //滚动计算辅助类  private Scroller mScroller;  //屏幕宽度  private int screenWidth;  //可以移动的最大距离  private int mMaxDistance;  //自定义手势监听类  private ScrollTouchLisener mTouchLisener;  //手势监听  private GestureDetector mDetector;  private BaseAdapter mAdapter;  /**   * 使用new关键字创建对象的时候调用   */  public ScrollViewGroup(Context context) {    this(context, null);  }  /**   * 在XML文件中使用的时候调用   */  public ScrollViewGroup(Context context, AttributeSet attrs) {    this(context, attrs, 0);  }  /**   * 在xml文件中调用，并且使用了自定义属性的时候调用   */  public ScrollViewGroup(Context context, AttributeSet attrs, int defStyleAttr) {    super(context, attrs, defStyleAttr);    init(context);  }  /**   * 初始化方法   * 初始化滚动辅助类Scroller以及计算出屏幕宽度   */  private void init(Context context) {    //初始化辅助类    mScroller = new Scroller(context);    //获取屏幕宽度    WindowManager manager = (WindowManager) context        .getSystemService(Context.WINDOW_SERVICE);    DisplayMetrics outMetrics = new DisplayMetrics();    manager.getDefaultDisplay().getMetrics(outMetrics);    screenWidth = outMetrics.widthPixels;    //手势指示器初始化    mTouchLisener = new ScrollTouchLisener();    mDetector = new GestureDetector(context, mTouchLisener);  }  /**   * 滚动时需要重写的方法，用于控制滚动   */  @Override  public void computeScroll() {    //判断滚动时候停止    if (mScroller.computeScrollOffset()) {      //滚动到指定的位置      scrollTo(mScroller.getCurrX(), mScroller.getCurrY());      //这句话必须写，否则不能实时刷新      invalidate();    }  }  /**   * 手指触屏事件监听   */  @Override  public boolean onTouchEvent(MotionEvent event) {    mDetector.onTouchEvent(event);    if (event.getAction() == MotionEvent.ACTION_UP) {      this.onUp(event);    }    return true;  }  public void setAdapter(BaseAdapter adapter) {    this.mAdapter = adapter;    requestLayout();  }  /*   *测量方法，测量父布局的宽度和高度   */  @Override  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    removeAllViews();    for (int i = 0; i < mAdapter.getCount(); i++) {      View child = mAdapter.getView(i, null, null);      addView(child);    }    //重新设置宽高    this.setMeasuredDimension(measureWidth(widthMeasureSpec, heightMeasureSpec), measureHeight(widthMeasureSpec, heightMeasureSpec));  }  /**   * 测量宽度   */  private int measureWidth(int widthMeasureSpec, int heightMeasureSpec) {    // 宽度    int sizeWidth = MeasureSpec.getSize(widthMeasureSpec);    int modeWidth = MeasureSpec.getMode(widthMeasureSpec);    //父控件的宽（wrap_content）    int width = 0;    int childCount = getChildCount();    //重新测量子view的宽度，以及最大高度    for (int i = 0; i < childCount; i++) {      View child = getChildAt(i);      measureChild(child, widthMeasureSpec, heightMeasureSpec);      // LayoutParams lp = child.getLayoutParams();      /* MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();      int childWidth = child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;      width += childWidth;*/      width += child.getMeasuredWidth();    }    return modeWidth == MeasureSpec.EXACTLY ? sizeWidth : width;  }  /**   * 测量高度   */  private int measureHeight(int widthMeasureSpec, int heightMeasureSpec) {    //高度    int sizeHeight = MeasureSpec.getSize(heightMeasureSpec);    int modeHeight = MeasureSpec.getMode(heightMeasureSpec);    //父控件的高（wrap_content）    int height = 0;    int childCount = getChildCount();    //重新测量子view的宽度，以及最大高度    for (int i = 0; i < childCount; i++) {      View child = getChildAt(i);      measureChild(child, widthMeasureSpec, heightMeasureSpec);      /* MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();      int childHeight = child.getMeasuredHeight() + lp.topMargin + lp.bottomMargin;      height += childHeight;*/      height += child.getMeasuredHeight();    }    height = height / childCount;    return modeHeight == MeasureSpec.EXACTLY ? sizeHeight : height;  }  /**   * 给子布局设定位置   */  @Override  protected void onLayout(boolean changed, int l, int t, int r, int b) {    int childLeft = 0;//子View左边的间距    int childWidth;//子View的宽度    int height = getHeight();//屏幕的宽度    int childCount = getChildCount();//子View的数量    for (int i = 0; i < childCount; i++) {      View child = getChildAt(i);     /*  MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();      childWidth = child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;*/      childWidth = child.getMeasuredWidth();      child.layout(childLeft, 0, childLeft + childWidth, height);      childLayout(child);      childLeft += childWidth;    }  }  /**   *让子View的子View和子View大小一样   */  private void childLayout(View child){    if (child==null){      throw new IllegalStateException("ScrollViewGroup must has one child");    }    if (child instanceof ViewGroup){      if(((ViewGroup)child).getChildCount()>0)        throw new IllegalStateException("view can host only one direct child");      ((ViewGroup) child).getChildAt(0).layout(0,0,child.getWidth(),child.getHeight());    }  }  @Override  public LayoutParams generateLayoutParams(AttributeSet attrs) {    return new MarginLayoutParams(getContext(), attrs);  }  /*   *按下事件 ACTION_DOWN   */  public boolean onDown(MotionEvent e) {    //得到最后一个子View    View lastChild = getChildAt(getChildCount() - 1);    //获取滑动的最大滑动距离（最后一个Child的右边框的坐标减去屏幕的宽度）    int finalyChild = (int) (lastChild.getX() + lastChild.getWidth() - screenWidth);    mMaxDistance = finalyChild;    //如果停止滚动则取消动画（即手指按下就停止滚动）    if (!mScroller.isFinished()) {      mScroller.abortAnimation();    }    return false;  }  /*  *抬起事件 ACTION_UP  */  public boolean onUp(MotionEvent e) {    //如果滑动的距离小于第一个控件的最左边（0）则回弹至（0,0）点    if (getScrollX() <= 0) {      scrollTo(0, 0);    }    //如果滑动的距离大于最大可滑动距离则滑动到最后一个子View    if (getScrollX() >= mMaxDistance) {      scrollTo(mMaxDistance, 0);    }    //刷新界面    invalidate();    return false;  }  /*   *ACTION_DOWN 、短按不移动   */  public void onShowPress(MotionEvent e) {  }  /*   *短按ACTION_DOWN、ACTION_UP   */  public boolean onSingleTapUp(MotionEvent e) {    return false;  }  /*   *ACTION_DOWN 、慢滑动   */  public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {    //滚动    scrollBy((int) distanceX, 0);    return false;  }  // ACTION_DOWN 、长按不滑动  public void onLongPress(MotionEvent e) {  }  /*   *ACTION_DOWN 、快滑动、 ACTION_UP   */  public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {    mScroller.fling(getScrollX(), 0, (int) -velocityX, 0, 0, mMaxDistance, 0, 0);    return false;  }  /**   * 自定义手势监听类   */  private class ScrollTouchLisener implements GestureDetector.OnGestureListener {    //按下事件    @Override    public boolean onDown(MotionEvent e) {      return ScrollViewGroup.this.onDown(e);    }    //单击事件    @Override    public void onShowPress(MotionEvent e) {      ScrollViewGroup.this.onShowPress(e);    }    //手指抬起事件    @Override    public boolean onSingleTapUp(MotionEvent e) {      return ScrollViewGroup.this.onSingleTapUp(e);    }    //滚动事件    @Override    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {      return ScrollViewGroup.this.onScroll(e1, e2, distanceX, distanceY);    }    //长按事件    @Override    public void onLongPress(MotionEvent e) {      ScrollViewGroup.this.onLongPress(e);    }    //滑动事件    @Override    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {      return ScrollViewGroup.this.onFling(e1, e2, velocityX, velocityY);    }  }}