package com.socks.zlistview.widget;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewTreeObserver.OnGlobalLayoutListener;
import android.view.animation.DecelerateInterpolator;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
import com.socks.zlistview.R;
/**
*
* @class: com.socks.zlistview.ZListView
* @author zhaokaiqiang
* @date 2015-1-4 下午10:37:06
*
*/
public class ZListView extends ListView {
private final static int SCROLLBACK_HEADER = 0;
private final static int SCROLLBACK_FOOTER = 1;
// 滑动时长
private final static int SCROLL_DURATION = 400;
// 加载更多的距离
private final static int PULL_LOAD_MORE_DELTA = 100;
// 滑动比例
private final static float OFFSET_RADIO = 2f;
// 记录按下点的y坐标
private float lastY;
// 用来回滚
private Scroller scroller;
private IXListViewListener mListViewListener;
private ZListViewHeader headerView;
private RelativeLayout headerViewContent;
// header的高度
private int headerHeight;
// 是否能够刷新
private boolean enableRefresh = true;
// 是否正在刷新
private boolean isRefreashing = false;
// footer
private ZListViewFooter footerView;
// 是否可以加载更多
private boolean enableLoadMore;
// 是否正在加载
private boolean isLoadingMore;
// 是否footer准备状态
private boolean isFooterAdd = false;
// item的总数
private int totalItemCount;
// 记录是从header还是footer返回
private int mScrollBack;
public ZListView(Context context) {
super(context);
initView(context);
}
public ZListView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
}
public ZListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initView(context);
}
private void initView(Context context) {
scroller = new Scroller(context, new DecelerateInterpolator());
headerView = new ZListViewHeader(context);
footerView = new ZListViewFooter(context);
headerViewContent = (RelativeLayout) headerView
.findViewById(R.id.xlistview_header_content);
headerView.getViewTreeObserver().addOnGlobalLayoutListener(
new OnGlobalLayoutListener() {
@SuppressWarnings("deprecation")
@Override
public void onGlobalLayout() {
headerHeight = headerViewContent.getHeight();
getViewTreeObserver()
.removeGlobalOnLayoutListener(this);
}
});
addHeaderView(headerView);
}
@Override
public void setAdapter(ListAdapter adapter) {
// 确保footer最后添加并且只添加一次
if (isFooterAdd == false) {
isFooterAdd = true;
addFooterView(footerView);
}
super.setAdapter(adapter);
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
totalItemCount = getAdapter().getCount();
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
// 记录按下的坐标
lastY = ev.getRawY();
break;
case MotionEvent.ACTION_MOVE:
// 计算移动距离
float deltaY = ev.getRawY() - lastY;
lastY = ev.getRawY();
// 是第一项并且标题已经显示或者是在下拉
if (getFirstVisiblePosition() == 0
&& (headerView.getVisiableHeight() > 0 || deltaY > 0)) {
updateHeaderHeight(deltaY / OFFSET_RADIO);
} else if (getLastVisiblePosition() == totalItemCount - 1
&& (footerView.getBottomMargin() > 0 || deltaY < 0)) {
updateFooterHeight(-deltaY / OFFSET_RADIO);
}
break;
case MotionEvent.ACTION_UP:
if (getFirstVisiblePosition() == 0) {
if (enableRefresh
&& headerView.getVisiableHeight() > headerHeight) {
isRefreashing = true;
headerView.setState(ZListViewHeader.STATE_REFRESHING);
if (mListViewListener != null) {
mListViewListener.onRefresh();
}
}
resetHeaderHeight();
} else if (getLastVisiblePosition() == totalItemCount - 1) {
if (enableLoadMore
&& footerView.getBottomMargin() > PULL_LOAD_MORE_DELTA) {
startLoadMore();
}
resetFooterHeight();
}
break;
}
return super.onTouchEvent(ev);
}
@Override
public void computeScroll() {
// 松手之后调用
if (scroller.computeScrollOffset()) {
if (mScrollBack == SCROLLBACK_HEADER) {
headerView.setVisiableHeight(scroller.getCurrY());
} else {
footerView.setBottomMargin(scroller.getCurrY());
}
postInvalidate();
}
super.computeScroll();
}
public void setPullRefreshEnable(boolean enable) {
enableRefresh = enable;
if (!enableRefresh) {
headerView.hide();
} else {
headerView.show();
}
}
public void setPullLoadEnable(boolean enable) {
enableLoadMore = enable;
if (!enableLoadMore) {
footerView.hide();
footerView.setOnClickListener(null);
} else {
isLoadingMore = false;
footerView.show();
footerView.setState(ZListViewFooter.STATE_NORMAL);
footerView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startLoadMore();
}
});
}
}
public void stopRefresh() {
if (isRefreashing == true) {
isRefreashing = false;
resetHeaderHeight();
}
}
public void stopLoadMore() {
if (isLoadingMore == true) {
isLoadingMore = false;
footerView.setState(ZListViewFooter.STATE_NORMAL);
}
}
private void updateHeaderHeight(float delta) {
headerView.setVisiableHeight((int) delta
+ headerView.getVisiableHeight());
// 未处于刷新状态，更新箭头
if (enableRefresh && !isRefreashing) {
if (headerView.getVisiableHeight() > headerHeight) {
headerView.setState(ZListViewHeader.STATE_READY);
} else {
headerView.setState(ZListViewHeader.STATE_NORMAL);
}
}
}
private void resetHeaderHeight() {
// 当前的可见高度
int height = headerView.getVisiableHeight();
// 如果正在刷新并且高度没有完全展示
if ((isRefreashing && height <= headerHeight) || (height == 0)) {
return;
}
// 默认会回滚到header的位置
int finalHeight = 0;
// 如果是正在刷新状态，则回滚到header的高度
if (isRefreashing && height > headerHeight) {
finalHeight = headerHeight;
}
mScrollBack = SCROLLBACK_HEADER;
// 回滚到指定位置
scroller.startScroll(0, height, 0, finalHeight - height,
SCROLL_DURATION);
// 触发computeScroll
invalidate();
}
private void updateFooterHeight(float delta) {
int height = footerView.getBottomMargin() + (int) delta;
if (enableLoadMore && !isLoadingMore) {
if (height > PULL_LOAD_MORE_DELTA) {
footerView.setState(ZListViewFooter.STATE_READY);
} else {
footerView.setState(ZListViewFooter.STATE_NORMAL);
}
}
footerView.setBottomMargin(height);
}
private void resetFooterHeight() {
int bottomMargin = footerView.getBottomMargin();
if (bottomMargin > 0) {
mScrollBack = SCROLLBACK_FOOTER;
scroller.startScroll(0, bottomMargin, 0, -bottomMargin,
SCROLL_DURATION);
invalidate();
}
}
private void startLoadMore() {
isLoadingMore = true;
footerView.setState(ZListViewFooter.STATE_LOADING);
if (mListViewListener != null) {
mListViewListener.onLoadMore();
}
}
public void setXListViewListener(IXListViewListener l) {
mListViewListener = l;
}
public interface IXListViewListener {
public void onRefresh();
public void onLoadMore();
}
}
