android自定义控件之ListView上拉加载与下拉刷新
自定义控件LoadLayout（只有上拉加载）（下拉刷新用控件android.support.v4.widget.SwipeRefreshLayout）(上拉与下拉继承让LoadLayout继承SwipeRefreshLayout即可)
使用方法（上拉implements LoadLayout.OnLoadListener，在onLoad()方法中实现加载操作）
（下拉implements SwipeRefreshLayout.OnRefreshListener，在onRefresh()方法中实现刷新操作）
import android.content.Context; import android.graphics.drawable.Animatable; import android.graphics.drawable.Drawable; import android.util.AttributeSet; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.View; import android.view.ViewConfiguration; import android.widget.AbsListView; import android.widget.FrameLayout; import android.widget.ListView; import android.widget.TextView; import com.xh.boke.R; /** * 自定义控件ListView上拉加载 * Created by Administrator on 2015/10/22 0022. */ public class LoadLayout extends FrameLayout implements AbsListView.OnScrollListener { private enum Operation { START, STOP } /** * 滑动到最下面时的上拉操作 */ private int mTouchSlop; /** * listview实例 */ private ListView mListView; /** * 底部文字 */ private TextView mFootText; /** * 上拉监听器, 到了最底部的上拉加载操作 */ private OnLoadListener mOnLoadListener; /** * ListView的加载中footer */ private View mListViewFooter; /** * 按下时的y坐标 */ private int mYDown; /** * 抬起时的y坐标, 与mYDown一起用于滑动到底部时判断是上拉还是下拉 */ private int mLastY; /** * 是否在加载中 ( 上拉加载更多 ) */ private boolean isLoading = false; /** * @param context */ public LoadLayout(Context context) { this(context, null); } public LoadLayout(Context context, AttributeSet attrs) { super(context, attrs); mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop(); mListViewFooter = LayoutInflater.from(context).inflate(R.layout.view_lv_footer, null, false); mFootText = (TextView) mListViewFooter.findViewById(R.id.pull_to_refresh_loadmore_text); } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { super.onLayout(changed, left, top, right, bottom); // 初始化ListView对象 if (mListView == null) { getListView(); } } /** * 获取ListView对象 */ private void getListView() { int childs = getChildCount(); if (childs > 0) { for (int i = 0; i < childs; i++) { View childView = getChildAt(i); if (childView instanceof ListView) { mListView = (ListView) childView; // 设置滚动监听器给ListView, 使得滚动的情况下也可以自动加载 mListView.setOnScrollListener(this); } } } } /* * (non-Javadoc) * @see android.view.ViewGroup#dispatchTouchEvent(android.view.MotionEvent) */ @Override public boolean dispatchTouchEvent(MotionEvent event) { final int action = event.getAction(); switch (action) { case MotionEvent.ACTION_DOWN: // 按下 mYDown = (int) event.getRawY(); break; case MotionEvent.ACTION_MOVE: // 移动 break; case MotionEvent.ACTION_UP: mLastY = (int) event.getRawY(); // 抬起 if (canLoad()) { loadData(); } break; default: break; } return super.dispatchTouchEvent(event); } /** * 是否可以加载更多, 条件是到了最底部, listview不在加载中, 且为上拉操作. * * @return */ private boolean canLoad() { return isBottom() && !isLoading && isPullUp(); } /** * 判断是否到了最底部 */ private boolean isBottom() { if (mListView != null && mListView.getAdapter() != null) { return mListView.getLastVisiblePosition() == (mListView.getAdapter().getCount() - 1); } return false; } /** * 是否是上拉操作 * * @return */ private boolean isPullUp() { return (mYDown - mLastY) >= mTouchSlop; } /** * 如果到了最底部,而且是上拉操作.那么执行onLoad方法 */ private void loadData() { if (mOnLoadListener != null) { // 设置状态 setLoading(true); // mOnLoadListener.onLoad(); } } /** * @param loading */ public void setLoading(boolean loading) { isLoading = loading; if (isLoading) { changeAnimation(Operation.START); mListView.addFooterView(mListViewFooter, null, false); } else { changeAnimation(Operation.STOP); mListView.removeFooterView(mListViewFooter); mYDown = 0; mLastY = 0; } } /** * @param loadListener */ public void setOnLoadListener(OnLoadListener loadListener) { mOnLoadListener = loadListener; } @Override public void onScrollStateChanged(AbsListView view, int scrollState) { } @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { // 滚动时到了最底部也可以加载更多 if (canLoad()) { loadData(); } } /** * 加载更多的监听器 * * @author mrsimple */ public static interface OnLoadListener { public void onLoad(); } private void changeAnimation(Operation operation) { Drawable[] drawables = mFootText.getCompoundDrawables(); for (Drawable drawable : drawables) { if (drawable != null && drawable instanceof Animatable) { Animatable animatable = ((Animatable) drawable); switch (operation) { case START: animatable.start(); break; case STOP: animatable.stop(); break; } } } } }
view_lv_footer.xml
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" android:background="#ffffff" android:gravity="center" android:paddingBottom="8dip" android:paddingTop="5dip" > <TextView android:id="@+id/pull_to_refresh_loadmore_text" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" android:gravity="center" android:paddingTop="5dip" android:drawableLeft="@anim/rotating_loading" android:drawablePadding="8dp" android:text="加载中..." android:textAppearance="?android:attr/textAppearanceMedium" android:textColor="@android:color/black" android:textSize="@dimen/activity_horizontal_margin" android:textStyle="bold" /> </RelativeLayout>
rotating_loading.xml
<?xml version="1.0" encoding="utf-8"?> <animated-rotate xmlns:android="http://schemas.android.com/apk/res/android" android:pivotX="50%" android:pivotY="50%" android:drawable="@mipmap/ic_ref" android:duration="10" />
在activity中使用
setContentView(R.layout.activity_main); LoadLayout load = (LoadLayout) findViewById(R.id.load); load.setOnLoadListener(this);
关闭loading
load.setLoading(false);
activity_main.xml
<?xml version="1.0" encoding="utf-8"?> <com.xh.boke.component.LoadLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/load" android:layout_width="match_parent" android:layout_height="match_parent"> <ListView android:id="@+id/lv" android:layout_width="match_parent" android:layout_height="match_parent" /> </com.xh.boke.component.LoadLayout>
