XListView：一个支持下拉刷新和上拉加载更多功能的自定义ListView-优快云博客

本文链接：https://blog.youkuaiyun.com/fuweiping/article/details/10118125
原控件 http://blog.youkuaiyun.com/fuweiping/article/details/8033035
/**
 * @file XListView.java
 * @package me.maxwin.view
 * @create Mar 18, 2012 6:28:41 PM
 * @author Maxwin
 * @description An ListView support (a) Pull down to refresh, (b) Pull up to load more.
 * 		Implement IXListViewListener, and see stopRefresh() / stopLoadMore().
 */
package com.reacnnCn.android.view.listview;

import com.reacnnCn.android.R;
import com.reacnnCn.android.utils.DateOperation;
import com.reacnnCn.android.utils.LogUtil;

import android.content.Context;
import android.graphics.Canvas;
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.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
import android.widget.TextView;

public class XListView extends ListView implements OnScrollListener {

	private float mLastY = -1; // save event y
	private Scroller mScroller; // used for scroll back
	private OnScrollListener mScrollListener; // user's scroll listener

	// the interface to trigger refresh and load more.
	private IXListViewListener mListViewListener;

	// -- header view
	private XListViewHeader mHeaderView;
	// header view content, use it to calculate the Header's height. And hide it
	// when disable pull refresh.
	private RelativeLayout mHeaderViewContent;
	private TextView mHeaderTimeView;
	private int mHeaderViewHeight; // header view's height
	private boolean mEnablePullRefresh = true;
	private boolean mPullRefreshing = false; // is refreashing.

	// -- footer view
	private XListViewFooter mFooterView;
	private boolean mEnablePullLoad;
	private boolean mPullLoading;
	private boolean mIsFooterReady = false;

	// total list items, used to detect is at the bottom of listview.
	private int mTotalItemCount;

	// for mScroller, scroll back from header or footer.
	private int mScrollBack;
	public boolean isCanRefresh = true;
	private final static int SCROLLBACK_HEADER = 0;
	private final static int SCROLLBACK_FOOTER = 1;

	private final static int SCROLL_DURATION = 400; // scroll back duration
	private final static int PULL_LOAD_MORE_DELTA = 75; // when pull up >= 50px
														// at bottom, trigger
														// load more.
	private final static float OFFSET_RADIO = 1.8f; // support iOS like pull

	/*
	 * add headerview 必须在setadapter之前
	 * 
	 * add footview 调用完之后 会notify dataobserver 必须在setadapter之前
	 */

	/**
	 * @param context
	 */
	public XListView(Context context) {
		super(context);
		initWithContext(context);
	}

	public XListView(Context context, AttributeSet attrs) {
		super(context, attrs);
		initWithContext(context);
	}

	public XListView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		initWithContext(context);
	}

	@SuppressWarnings("deprecation")
	private void initWithContext(Context context) {
		mScroller = new Scroller(context, new DecelerateInterpolator());
		super.setOnScrollListener(this);

		mHeaderView = new XListViewHeader(context);
		mHeaderViewContent = (RelativeLayout) mHeaderView
				.findViewById(R.id.xlistview_header_content);
		mHeaderTimeView = (TextView) mHeaderView
				.findViewById(R.id.xlistview_header_time);
		addHeaderView(mHeaderView, null, false);
		mFooterView = new XListViewFooter(context);
		mHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(
				new OnGlobalLayoutListener() {
					@Override
					public void onGlobalLayout() {
						mHeaderViewHeight = mHeaderViewContent.getHeight();
						getViewTreeObserver()
								.removeGlobalOnLayoutListener(this);
					}
				});

	}

	/**
	 * enable or disable pull down refresh feature.
	 * 
	 * @param enable
	 */
	public void setPullRefreshEnable(boolean enable) {
		mEnablePullRefresh = enable;
		if (!mEnablePullRefresh) {
			mHeaderViewContent.setVisibility(View.INVISIBLE);
		} else {
			mHeaderViewContent.setVisibility(View.VISIBLE);
		}
	}

	/**
	 * enable or disable pull up load more feature.
	 * 
	 * @param enable
	 */
	public void setPullLoadEnable(boolean enable) {
		mEnablePullLoad = enable;
		if (!mEnablePullLoad) {
			mFooterView.hide();
			mFooterView.setOnClickListener(null);
		} else {
			mPullLoading = false;
			mFooterView.show();
			mFooterView.setState(XListViewFooter.STATE_NORMAL);
			mFooterView.setOnClickListener(new OnClickListener() {
				@Override
				public void onClick(View v) {
					startLoadMore();
				}
			});
		}
	}

	/**
	 * stop refresh, reset header view.
	 */
	public void stopRefresh() {
		if (mPullRefreshing == true) {
			mPullRefreshing = false;
			resetHeaderHeight();
			mHeaderView.setState(XListViewHeader.STATE_NORMAL);
		}
	}

	/**
	 * stop load more, reset footer view.
	 */
	public void stopLoadMore() {
		if (mPullLoading == true) {
			mPullLoading = false;
			mFooterView.setState(XListViewFooter.STATE_NORMAL);
		}
	}

	/**
	 * set last refresh time
	 * 
	 * @param time
	 */
	public void setRefreshTime(String time) {
		mHeaderTimeView.setText(time);
	}

	private void invokeOnScrolling() {
		if (mScrollListener instanceof OnXScrollListener) {
			OnXScrollListener l = (OnXScrollListener) mScrollListener;
			l.onXScrolling(this);
		}
	}

	private void updateHeaderHeight(float delta) {
		mHeaderView.setVisiableHeight((int) delta
				+ mHeaderView.getVisiableHeight());
		if (mEnablePullRefresh && !mPullRefreshing) {
			if (mHeaderView.getVisiableHeight() != 0) {
				if (mHeaderView.getVisiableHeight() > mHeaderViewHeight + 30) {
					mHeaderView.setState(XListViewHeader.STATE_READY);
				} else {
					mHeaderView.setState(XListViewHeader.STATE_NORMAL);
				}
			} else {
				mHeaderView.setState(XListViewHeader.STATE_READY);
			}
		}
		setSelection(0);
	}

	/**
	 * reset header view's height.
	 */
	private void resetHeaderHeight() {
		int height = mHeaderView.getVisiableHeight();
		if (height == 0)
			return;

		if (mPullRefreshing && height <= mHeaderViewHeight) {
			return;
		}
		int finalHeight = 0;

		if (mPullRefreshing && height > mHeaderViewHeight) {
			finalHeight = mHeaderViewHeight;
		}
		mScrollBack = SCROLLBACK_HEADER;
		mScroller.startScroll(0, height, 0, finalHeight - height,
				SCROLL_DURATION);
		invalidate();
	}

	private void updateFooterHeight(float delta) {
		int height = mFooterView.getBottomMargin() + (int) delta;
		if (mEnablePullLoad && !mPullLoading) {
			if (height > PULL_LOAD_MORE_DELTA) {
				mFooterView.setState(XListViewFooter.STATE_READY);
			} else {
				mFooterView.setState(XListViewFooter.STATE_NORMAL);
			}
		}
		mFooterView.setBottomMargin(height);
	}

	private void resetFooterHeight() {
		int bottomMargin = mFooterView.getBottomMargin();
		if (bottomMargin > 0) {
			mScrollBack = SCROLLBACK_FOOTER;
			mScroller.startScroll(0, bottomMargin, 0, -bottomMargin,
					SCROLL_DURATION);
			invalidate();
		}
	}

	private void startLoadMore() {
		mPullLoading = true;
		// SetHeaderViewNormal();
		if (mFooterView.getState() != XListViewFooter.STATE_LOADING
				&& mHeaderView.getState() != XListViewHeader.STATE_REFRESHING) {
			mFooterView.setState(XListViewFooter.STATE_LOADING);
			if (mListViewListener != null) {
				mListViewListener.onLoadMore();
				invalidate();
			}
		} else {
			LogUtil.e(VIEW_LOG_TAG, "loading more now", false);
		}
	}

	private void startLoadfresh() {
		mPullRefreshing = true;
		if (mHeaderView.getState() != XListViewHeader.STATE_REFRESHING
				&& mFooterView.getState() != XListViewFooter.STATE_LOADING) {
			mHeaderView.setState(XListViewHeader.STATE_REFRESHING);
			if (mListViewListener != null) {
				mListViewListener.onRefresh();
				setRefreshTime(DateOperation.GetSysCurrentTime());
			}
		} else {
			LogUtil.e(VIEW_LOG_TAG, "on refresh now", false);
		}
	}

	@Override
	public boolean onTouchEvent(MotionEvent ev) {
		if (mLastY == -1) {
			mLastY = ev.getRawY();
		}
		switch (ev.getAction()) {
		case MotionEvent.ACTION_DOWN:
			mLastY = ev.getRawY();
			break;
		case MotionEvent.ACTION_MOVE:
			final float deltaY = ev.getRawY() - mLastY;
			mLastY = ev.getRawY();
			if (getFirstVisiblePosition() == 0
					&& (mHeaderView.getVisiableHeight() > 0 || deltaY > 0)) {
				updateHeaderHeight(deltaY / OFFSET_RADIO);
				invokeOnScrolling();
			} else if (getLastVisiblePosition() == mTotalItemCount - 1
					&& (mFooterView.getBottomMargin() > 0 || deltaY < 0)) {
				updateFooterHeight(-deltaY / OFFSET_RADIO);
			}
			break;
		default:
			mLastY = -1;
			if (getFirstVisiblePosition() == 0) {
				if (mEnablePullRefresh
						&& mHeaderView.getVisiableHeight() > mHeaderViewHeight) {
					startLoadfresh();
				}
				resetHeaderHeight();
			} else if (getLastVisiblePosition() == mTotalItemCount - 1) {
				if (mEnablePullLoad
						&& mFooterView.getBottomMargin() > PULL_LOAD_MORE_DELTA
						&& mIsFooterReady) {
					if (mHeaderView.getState() == XListViewHeader.STATE_NORMAL) {
						// 下拉刷新为默认状态的时候,执行加载更多
						startLoadMore();
					}
				}
				resetFooterHeight();
			}
			break;
		}
		return super.onTouchEvent(ev);
	}

	@Override
	public void computeScroll() {
		if (mScroller.computeScrollOffset()) {
			if (mScrollBack == SCROLLBACK_HEADER) {
				mHeaderView.setVisiableHeight(mScroller.getCurrY());
			} else {
				mFooterView.setBottomMargin(mScroller.getCurrY());
			}
			postInvalidate();
			invokeOnScrolling();
		}
		super.computeScroll();
	}

	@Override
	public void setOnScrollListener(OnScrollListener l) {
		mScrollListener = l;
	}

	@Override
	public void onScrollStateChanged(AbsListView view, int scrollState) {
		if (mScrollListener != null) {
			mScrollListener.onScrollStateChanged(view, scrollState);
		}
	}

	@Override
	public void onScroll(AbsListView view, int firstVisibleItem,
			int visibleItemCount, int totalItemCount) {
		mTotalItemCount = totalItemCount;
		if (mScrollListener != null) {
			mScrollListener.onScroll(view, firstVisibleItem, visibleItemCount,
					totalItemCount);
		}
	}

	public void setXListViewListener(IXListViewListener l) {
		mListViewListener = l;
	}

	/**
	 * you can listen ListView.OnScrollListener or this one. it will invoke
	 * onXScrolling when header/footer scroll back.
	 */
	public interface OnXScrollListener extends OnScrollListener {
		public void onXScrolling(View view);
	}

	/**
	 * implements this interface to get refresh/load more event.
	 */
	public interface IXListViewListener {
		public void onRefresh();

		public void onLoadMore();
	}

	@Override
	public void setAdapter(ListAdapter adapter) {
		if (mIsFooterReady == false) {
			mIsFooterReady = true;
			if (this.getFooterViewsCount() <= 0) {
				addFooterView(mFooterView, null, false);
			}
		}
		super.setAdapter(adapter);
	}

	@Override
	protected void dispatchDraw(Canvas canvas) {
		try {
			super.dispatchDraw(canvas);
		} catch (IndexOutOfBoundsException e) {
			LogUtil.e(VIEW_LOG_TAG, "", e, false);
		}
	}

	public void SetRefreshPadding() {
		if (mHeaderView != null) {
			updateHeaderHeight(mHeaderViewHeight);
			startLoadfresh();
		}
	}

}
修改下拉刷新的一个控件
