android 按照字母排序，修改后的

package com.testcontact; import android.content.Context; import android.graphics.Canvas; import android.util.AttributeSet; import android.view.LayoutInflater; import android.view.View; import android.widget.AbsListView; import android.widget.ListView; import android.widget.TextView; import android.widget.AbsListView.OnScrollListener; public class MyListView extends ListView implements OnScrollListener{ //隐藏状态 public static final int PINNED_HEADER_GONE = 0; //显示状态 public static final int PINNED_HEADER_VISIBLE = 1; // 表示mHeaderView在上升状态 public static final int PINNED_HEADER_PUSHED_UP = 2; //表示mHeaderView在下拉状态 public static final int PINNED_HEADER_PUSHED_DOWN = 3; private View mHeaderView;//最上边的头标签 private int mHeaderViewId;//头标签的id -- R.id.XXXX private boolean mHeaderViewVisible = false;//是否显示头标签 private int mHeaderViewY = 0;//头标签应该显示的Y轴坐标 private int mHeaderViewAlpha = 255;//头标签的透明度 private int lastBottom = 0;//保存头标签应该显示的Y轴坐标 private String mHeaderViewText = "A"; private int mHeaderViewstate = PINNED_HEADER_VISIBLE; private int mHeaderViewWidth; private int mHeaderViewHeight; public MyListView(Context context, AttributeSet attrs) { super(context, attrs); this.setOnScrollListener(this);//给listview设置OnScrollListener } public MyListView(Context context) { super(context); this.setOnScrollListener(this);//给listview设置OnScrollListener } public MyListView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); this.setOnScrollListener(this);//给listview设置OnScrollListener } /** * 设置头标签控件 * @param context 上下文对象 * @param layout 头标签的layout * @param viewId头标签的ID */ public void setPinnedHeaderView(Context context, int layout, int textViewId) { //根据控件layout和上下文对象生成头标签VIew mHeaderView = LayoutInflater.from(context).inflate(layout, this, false); mHeaderViewId = textViewId;//保存文本控件的id // Disable vertical fading when the pinned header is present // TODO change ListView to allow separate measures for top and bottom fading edge; // in this particular case we would like to disable the top, but not the bottom edge. if (mHeaderView != null) { setFadingEdgeLength(0);//设置边缘退色，没有设置的拖动listview上下边缘会出现颜色 } requestLayout();//调整布局 } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (mHeaderView != null) { measureChild(mHeaderView, widthMeasureSpec, heightMeasureSpec); mHeaderViewWidth = mHeaderView.getMeasuredWidth();//获得头标签的宽高 mHeaderViewHeight = mHeaderView.getMeasuredHeight(); } } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { super.onLayout(changed, left, top, right, bottom); if (mHeaderView != null) { mHeaderView.layout(0, 0, mHeaderViewWidth, mHeaderViewHeight);//配置下头标签的显示位置 configureHeaderView();//配置下头标签（显示位置，颜色，透明度字体等） } } @Override protected void dispatchDraw(Canvas canvas) { super.dispatchDraw(canvas); if (mHeaderViewVisible && mHeaderView != null) { drawChild(canvas, mHeaderView, getDrawingTime());//绘制头标签到listview上 } } /** * 配置头标签（显示位置，颜色，透明度字体等） * @param position */ public void configureHeaderView() { if (mHeaderView == null) { return; } switch (mHeaderViewstate) { case PINNED_HEADER_GONE: {//头标签不显示 mHeaderViewVisible = false; break; } case PINNED_HEADER_VISIBLE: {//头表签显示（默认状态） configurePinnedHeader(mHeaderView, 255);//设置头标签的文字和透明度等 if (mHeaderView.getTop() != 0) { mHeaderView.layout(0, 0, mHeaderViewWidth, mHeaderViewHeight);//设置头标签的显示位置（最初的默认原始状态） } mHeaderViewVisible = true; break; } case PINNED_HEADER_PUSHED_UP: {//头标签上升状态 mHeaderView.layout(0, mHeaderViewY, mHeaderViewWidth, mHeaderViewHeight + mHeaderViewY); mHeaderViewVisible = true; break; } case PINNED_HEADER_PUSHED_DOWN://头标签的下拉状态 mHeaderView.layout(0, mHeaderViewY, mHeaderViewWidth, mHeaderViewHeight + mHeaderViewY); mHeaderViewVisible = true; break; } } /** * 设置头标签的显示文本和状态 * @param mHeaderViewText 文本内容 * @param mHeaderViewstate 标签状态 */ public void setHeaderViewTextAndState(String mHeaderViewText, int mHeaderViewstate) { this.mHeaderViewText = mHeaderViewText; this.mHeaderViewstate = mHeaderViewstate; refreshView(getChildCount());//刷新头标签 } /** * 设置是否显示头标签是否显示 * @param mHeaderViewVisible */ public void setmHeaderViewVisible(boolean mHeaderViewVisible) { this.mHeaderViewVisible = mHeaderViewVisible; } /** * 配置头标签 * @param header 头标签 * @param alpha 透明度 */ public void configurePinnedHeader(View header, int alpha) { TextView lSectionHeader = (TextView)header; lSectionHeader.setText(mHeaderViewText); lSectionHeader.setBackgroundColor(alpha << 24 | (0xced2d7)); lSectionHeader.setTextColor(alpha << 24 | (0x000000)); } @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { refreshView(visibleItemCount);//刷新头标签 } @Override public void onScrollStateChanged(AbsListView view, int scrollState) { // TODO Auto-generated method stub // System.out.println("scrollState :" + scrollState); } /** * 刷新头标签 * @param visibleItemCount listview显示的列数 */ private void refreshView(int visibleItemCount) { View firstView = getChildAt(0);//获得显示的第一个控件 View secondView = null; if(visibleItemCount > 2) { secondView = getChildAt(1);//获得显示的第二个控件 } if(secondView == null)//无第二项，也就没有拖动的必要，不用进行对头标签的绘制变化 { configureHeaderView();//刷新头标签，然后return return; } //获得第一和第二个项的标签 View firstTvCatalog = firstView.findViewById(mHeaderViewId); View secondTvCatalog = secondView.findViewById(mHeaderViewId); if(firstTvCatalog == null || secondTvCatalog == null)//无 { configureHeaderView();//刷新头标签，然后return return; } if(secondTvCatalog.getVisibility() == View.GONE && firstTvCatalog.getVisibility() == View.GONE) { mHeaderViewstate = PINNED_HEADER_VISIBLE;//恢复默认的状态 } if (firstView != null) {//第一项存在 mHeaderViewText = (String) firstTvCatalog.getTag();//获得第一项的标签保存的文本 int firstBottom = firstView.getBottom();//获得第一项的底部距离顶部的高度 int hea