package cn.mutils.app.ui;
import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.AnimationUtils;
import android.view.animation.RotateAnimation;
import android.webkit.WebView;
import android.widget.AdapterView;
import android.widget.RelativeLayout;
import android.widget.ScrollView;
import android.widget.TextView;
import java.util.Timer;
import java.util.TimerTask;
import cn.mutils.app.R;
/**
* PullLayout refer to
* http://blog.csdn.net/zhongkejingwang/article/details/38868463
*/
@SuppressLint({"HandlerLeak", "InflateParams"})
@SuppressWarnings({"deprecation", "FieldCanBeLocal", "unused"})
public class PullLayout extends RelativeLayout {
public interface OnRefreshListener {
void onRefresh(PullLayout pullLayout);
void onLoadMore(PullLayout pullLayout);
}
public static final int STATAE_INIT = 0;
public static final int STATE_RELEASE_TO_REFRESH = 1;
public static final int STATE_REFRESHING = 2;
public static final int STATE_RELEASE_TO_LOAD = 3;
public static final int STATE_LOADING = 4;
public static final int STATE_DONE = 5;
private int state = STATAE_INIT;
private OnRefreshListener mListener;
private float downY, lastY;
/**
* Pull down distance.pullDownY and pullUpY can not be same as zero
*/
public float pullDownY = 0;
/**
* Pull up distance
*/
private float pullUpY = 0;
/**
* Refresh distance
*/
private float refreshDist = 200;
/**
* Load more distance
*/
private float loadMoreDist = 200;
private MyTimer timer;
public float MOVE_SPEED = 8;
/**
* First layout
*/
private boolean isLayout = false;
/**
* Touch on refreshing
*/
private boolean isTouch = false;
/**
* 手指滑动距离与下拉头的滑动距离比，中间会随正切函数变化
*/
private float radio = 2;
/**
* Arrow animation
*/
private RotateAnimation reverseAnimation;
/**
* Pull down head view
*/
private View refreshHeadView;
/**
* Pull down arrow view
*/
private View pullDownView;
/**
* Refreshing icon
*/
private View refreshingView;
/**
* Refresh state TextView
*/
private TextView refreshStateTextView;
/**
* Pull up foot view
*/
private View loadmoreFootView;
/**
* Pull up arrow view
*/
private View pullUpView;
/**
* Loading icon
*/
private View loadingView;
/**
* Load state TextView
*/
private TextView loadStateTextView;
/**
* Pull View who is real view for content
*/
private View pullView;
/**
* Filter one more touch point
*/
private int mEvents;
/**
* Whether it can pull down while touching
*/
private boolean canPullDown = true;
/**
* Whether it can pull up while touching
*/
private boolean canPullUp = true;
/**
* Whether pull down enabled
*/
protected boolean mPullDownEnabled = true;
/**
* Whether pull up enabled
*/
protected boolean mPullUpEnabled = true;
/**
* Policy for pull down and pull up
*/
protected PullPolicy mPolicy = new PullPolicy();
/**
* Hander for back-rolling
*/
Handler updateHandler = new Handler(Looper.getMainLooper()) {
@Override
public void handleMessage(Message msg) {
// 回弹速度随下拉距离moveDeltaY增大而增大
MOVE_SPEED = (float) (8
+ 5 * Math.tan(Math.PI / 2 / getMeasuredHeight() * (pullDownY + Math.abs(pullUpY))));
if (!isTouch) {
// 正在刷新，且没有往上推的话则悬停，显示"正在刷新..."
if (state == STATE_REFRESHING && pullDownY <= refreshDist) {
pullDownY = refreshDist + MOVE_SPEED;
timer.cancel();
} else if (state == STATE_LOADING && -pullUpY <= loadMoreDist) {
pullUpY = -loadMoreDist - MOVE_SPEED;
timer.cancel();
}
}
if (pullDownY > 0)
pullDownY -= MOVE_SPEED;
else if (pullUpY < 0)
pullUpY += MOVE_SPEED;
if (pullDownY < 0) {
// 已完成回弹
pullDownY = 0;
pullDownView.clearAnimation();
// 隐藏下拉头时有可能还在刷新，只有当前状态不是正在刷新时才改变状态
if (state != STATE_REFRESHING && state != STATE_LOADING)
changeState(STATAE_INIT);
timer.cancel();
requestLayout();
}
if (pullUpY > 0) {
// 已完成回弹
pullUpY = 0;
pullUpView.clearAnimation();
// 隐藏下拉头时有可能还在刷新，只有当前状态不是正在刷新时才改变状态
if (state != STATE_REFRESHING && state != STATE_LOADING)
changeState(STATAE_INIT);
timer.cancel();
}
// 刷新布局,会自动调用onLayout
requestLayout();
}
};
public PullLayout(Context context) {
super(context);
init(context, null);
}
public PullLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs);
}
public PullLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs);
}
private void init(Context context, AttributeSet attrs) {
timer = new MyTimer(updateHandler);
reverseAnimation = (RotateAnimation) AnimationUtils.loadAnimation(context, R.anim.pull_reverse);
LayoutInflater inflater = LayoutInflater.from(context);
refreshHeadView = inflater.inflate(R.layout.pull_refresh_head, null);
loadmoreFootView = inflater.inflate(R.layout.pull_load_more, null);
// 初始化下拉布局
pullDownView = refreshHeadView.findViewById(R.id.pull_icon);
refreshStateTextView = (TextView) refreshHeadView.findViewById(R.id.state_tv);
refreshingView = refreshHeadView.findViewById(R.id.refreshing_icon);
// 初始化上拉布局
pullUpView = loadmoreFootView.findViewById(R.id.pullup_icon);
loadStateTextView = (TextView) loadmoreFootView.findViewById(R.id.loadstate_tv);
loadingView = loadmoreFootView.findViewById(R.id.loading_icon);
if (attrs != null) {
TypedArray typedArray = context.obtainStyledAttributes(R.styleable.PullLayout);
int textSize = typedArray.getDimensionPixelSize(R.styleable.PullLayout_android_textSize, 0);
if (textSize != 0) {
refreshStateTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
loadStateTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
}
ColorStateList textColor = typedArray.getColorStateList(R.styleable.PullLayout_android_textColor);
if (textColor != null) {
refreshStateTextView.setTextColor(textColor);
loadStateTextView.setTextColor(textColor);
}
typedArray.recycle();
}
refreshHeadView.setBackgroundDrawable(this.getBackground());
loadmoreFootView.setBackgroundDrawable(this.getBackground());
}
public void setTextColor(int textColor) {
refreshStateTextView.setTextColor(textColor);
loadStateTextView.setTextColor(textColor);
}
public void setTextSize(float size) {
refreshStateTextView.setTextSize(size);
loadStateTextView.setTextSize(size);
}
public PullPolicy getPolicy() {
return mPolicy;
}
public void setPolicy(PullPolicy policy) {
mPolicy = policy;
}
public boolean isPullDownEnabled() {
return mPullDownEnabled;
}
public boolean isPullUpEnabled() {
return mPullUpEnabled;
}
public void setPullDownEnabled(boolean enabled) {
if (mPullDownEnabled == enabled) {
return;
}
mPullDownEnabled = enabled;
changeState(STATE_DONE);
hide();
}
public void setPullUpEnabled(boolean enabled) {
if (mPullUpEnabled == enabled) {
return;
}
mPullUpEnabled = enabled;
changeState(STATE_DONE);
hide();
}
public View getPullView() {
return pullView;
}
public void ensureHeadFoot() {
if (this.getChildCount() == 3) {
if (this.getChildAt(0) != refreshHeadView) {
throw new UnsupportedOperationException();
}
if (this.getChildAt(1) != pullView) {
throw new UnsupportedOperationException();
}
if (this.getChildAt(2) != loadmoreFootView) {
throw new UnsupportedOperationException();
}
return;
}
if (this.getChildCount() != 1) {
throw new UnsupportedOperationException("PullLayout must has only one child view");
}
View v = this.getChildAt(0);
if (v.getLayoutParams().height != LayoutParams.MATCH_PARENT) {
throw new UnsupportedOperationException();
}
pullView = v;
this.addView(refreshHeadView, 0, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
this.addView(loadmoreFootView, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
}
public void setOnRefreshListener(OnRefreshListener listener) {
mListener = listener;
}
protected void onFinishInflate() {
super.onFinishInflate();
ensureHeadFoot();
}
private void hide() {
timer.schedule(5);
}
public void onRefreshComplete() {
changeState(STATE_DONE);
hide();
}
public void onLoadMoreComplete() {
changeState(STATE_DONE);
hide();
}
private void changeState(int to) {
state = to;
switch (state) {
case STATAE_INIT:
// 下拉布局初始状态
refreshingView.setVisibility(View.GONE);
refreshStateTextView.setText(R.string.pull_to_refresh);
pullDownView.clearAnimation();
pullDownView.setVisibility(View.VISIBLE);
// 上拉布局初始状态
loadingView.setVisibility(View.GONE);
loadStateTextView.setText(R.string.pull_up_to_load);
pullUpView.clearAnimation();
pullUpView.setVisibility(View.VISIBLE);
break;
case STATE_RELEASE_TO_REFRESH:
// 释放刷新状态
refreshStateTextView.setText(R.string.pull_release_to_refresh);
pullDownView.startAnimation(reverseAnimation);
break;
case STATE_REFRESHING:
// 正在刷新状态
pullDownView.clearAnimation();
refreshingView.setVisibility(View.VISIBLE);
pullDownView.setVisibility(View.GONE);
refreshStateTextView.setText(R.string.pull_refreshing);
break;
case STATE_RELEASE_TO_LOAD:
// 释放加载状态
loadStateTextView.setText(R.string.pull_release_to_load);
pullUpView.startAnimation(reverseAnimation);
break;
case STATE_LOADING:
// 正在加载状态
pullUpView.clearAnimation();
loadingView.setVisibility(View.VISIBLE);
pullUpView.setVisibility(View.GONE);
loadStateTextView.setText(R.string.pull_loading);
break;
case STATE_DONE:
// 刷新或加载完毕，啥都不做
break;
}
}
/**
* 不限制上拉或下拉
*/
private void releasePull() {
canPullDown = true;
canPullUp = true;
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
switch (ev.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
downY = ev.getY();
lastY = downY;
timer.cancel();
mEvents = 0;
releasePull();
break;
case MotionEvent.ACTION_POINTER_DOWN:
case MotionEvent.ACTION_POINTER_UP:
// 过滤多点触碰
mEvents = -1;
break;
case MotionEvent.ACTION_MOVE:
if (mEvents == 0) {
if (mPullDownEnabled && (pullDownY > 0
|| (mPolicy.canPullDown(pullView) && canPullDown && state != STATE_LOADING))) {
// 可以下拉，正在加载时不能下拉
// 对实际滑动距离做缩小，造成用力拉的感觉
pullDownY = pullDownY + (ev.getY() - lastY) / radio;
if (pullDownY < 0) {
pullDownY = 0;
canPullDown = false;
canPullUp = true;
}
if (pullDownY > getMeasuredHeight())
pullDownY = getMeasuredHeight();
if (state == STATE_REFRESHING) {
// 正在刷新的时候触摸移动
isTouch = true;
}
} else if (mPullUpEnabled
&& (pullUpY < 0 || (mPolicy.canPullUp(pullView) && canPullUp && state != STATE_REFRESHING))) {
// 可以上拉，正在刷新时不能上拉
pullUpY = pullUpY + (ev.getY() - lastY) / radio;
if (pullUpY > 0) {
pullUpY = 0;
canPullDown = true;
canPullUp = false;
}
if (pullUpY < -getMeasuredHeight())
pullUpY = -getMeasuredHeight();
if (state == STATE_LOADING) {
// 正在加载的时候触摸移动
isTouch = true;
}
} else
releasePull();
} else
mEvents = 0;
lastY = ev.getY();
// 根据下拉距离改变比例
radio = (float) (2 + 2 * Math.tan(Math.PI / 2 / getMeasuredHeight() * (pullDownY + Math.abs(pullUpY))));
requestLayout();
if (pullDownY > 0) {
if (pullDownY <= refreshDist && (state == STATE_RELEASE_TO_REFRESH || state == STATE_DONE)) {
// 如果下拉距离没达到刷新的距离且当前状态是释放刷新，改变状态为下拉刷新
changeState(STATAE_INIT);
}
if (pullDownY >= refreshDist && state == STATAE_INIT) {
// 如果下拉距离达到刷新的距离且当前状态是初始状态刷新，改变状态为释放刷新
changeState(STATE_RELEASE_TO_REFRESH);
}
} else if (pullUpY < 0) {
// 下面是判断上拉加载的，同上，注意pullUpY是负值
if (-pullUpY <= loadMoreDist && (state == STATE_RELEASE_TO_LOAD || state == STATE_DONE)) {
changeState(STATAE_INIT);
}
// 上拉操作
if (-pullUpY >= loadMoreDist && state == STATAE_INIT) {
changeState(STATE_RELEASE_TO_LOAD);
}
}
// 因为刷新和加载操作不能同时进行，所以pullDownY和pullUpY不会同时不为0，因此这里用(pullDownY +
// Math.abs(pullUpY))就可以不对当前状态作区分了
if ((pullDownY + Math.abs(pullUpY)) > 8) {
// 防止下拉过程中误触发长按事件和点击事件
ev.setAction(MotionEvent.ACTION_CANCEL);
}
break;
case MotionEvent.ACTION_UP:
if (pullDownY > refreshDist || -pullUpY > loadMoreDist)
// 正在刷新时往下拉（正在加载时往上拉），释放后下拉头（上拉头）不隐藏
isTouch = false;
if (state == STATE_RELEASE_TO_REFRESH) {
changeState(STATE_REFRESHING);
// 刷新操作
if (mListener != null)
mListener.onRefresh(this);
} else if (state == STATE_RELEASE_TO_LOAD) {
changeState(STATE_LOADING);
// 加载操作
if (mListener != null)
mListener.onLoadMore(this);
}
hide();
default:
break;
}
// 事件分发交给父类
super.dispatchTouchEvent(ev);
return true;
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
if (!isLayout) {
// 这里是第一次进来的时候做一些初始化
ensureHeadFoot();
isLayout = true;
refreshDist = ((ViewGroup) refreshHeadView).getChildAt(0).getMeasuredHeight();
loadMoreDist = ((ViewGroup) loadmoreFootView).getChildAt(0).getMeasuredHeight();
}
// 改变子控件的布局，这里直接用(pullDownY + pullUpY)作为偏移量，这样就可以不对当前状态作区分
refreshHeadView.layout(0, (int) (pullDownY + pullUpY) - refreshHeadView.getMeasuredHeight(),
refreshHeadView.getMeasuredWidth(), (int) (pullDownY + pullUpY));
pullView.layout(0, (int) (pullDownY + pullUpY), pullView.getMeasuredWidth(),
(int) (pullDownY + pullUpY) + pullView.getMeasuredHeight());
loadmoreFootView.layout(0, (int) (pullDownY + pullUpY) + pullView.getMeasuredHeight(),
loadmoreFootView.getMeasuredWidth(),
(int) (pullDownY + pullUpY) + pullView.getMeasuredHeight() + loadmoreFootView.getMeasuredHeight());
}
@SuppressWarnings({"SimplifiableIfStatement", "RedundantIfStatement"})
public static class PullPolicy {
public boolean canPullDown(View v) {
if (v == null) {
return false;
}
if (v instanceof AdapterView<?>) {
return canPullDown((AdapterView<?>) v);
}
if (v instanceof ScrollView) {
return canPullDown((ScrollView) v);
}
if (v instanceof WebView) {
return canPullDown((WebView) v);
}
return true;
}
public boolean canPullUp(View v) {
if (v == null) {
return false;
}
if (v instanceof AdapterView<?>) {
return canPullUp((AdapterView<?>) v);
}
if (v instanceof ScrollView) {
return canPullUp((ScrollView) v);
}
if (v instanceof WebView) {
return canPullUp((WebView) v);
}
return true;
}
protected boolean canPullDown(AdapterView<?> v) {
if (v == null) {
return false;
}
if (v.getCount() == 0) {
// 没有item的时候也可以下拉刷新
return true;
} else if (v.getFirstVisiblePosition() == 0 && v.getChildAt(0).getTop() >= 0) {
// 滑到顶部了
return true;
} else
return false;
}
protected boolean canPullUp(AdapterView<?> v) {
if (v == null) {
return false;
}
if (v.getCount() == 0) {
// 没有item的时候也可以上拉加载
return true;
} else if (v.getLastVisiblePosition() == (v.getCount() - 1)) {
// 滑到底部了
if (v.getChildAt(v.getLastVisiblePosition() - v.getFirstVisiblePosition()) != null
&& v.getChildAt(v.getLastVisiblePosition() - v.getFirstVisiblePosition()).getBottom() <= v
.getMeasuredHeight())
return true;
}
return false;
}
protected boolean canPullDown(ScrollView v) {
if (v == null) {
return false;
}
if (v.getScrollY() == 0)
return true;
else
return false;
}
protected boolean canPullUp(ScrollView v) {
if (v == null) {
return false;
}
if (v.getScrollY() >= (v.getChildAt(0).getHeight() - v.getMeasuredHeight()))
return true;
else
return false;
}
protected boolean canPullDown(WebView v) {
if (v == null) {
return false;
}
if (v.getScrollY() == 0)
return true;
else
return false;
}
protected boolean canPullUp(WebView v) {
if (v == null) {
return false;
}
if (v.getScrollY() >= Math.floor(v.getContentHeight() * v.getScale() - v.getMeasuredHeight()))
return true;
else
return false;
}
}
class MyTimer {
private Handler handler;
private Timer timer;
private MyTask mTask;
public MyTimer(Handler handler) {
this.handler = handler;
timer = new Timer();
}
public void schedule(long period) {
if (mTask != null) {
mTask.cancel();
mTask = null;
}
mTask = new MyTask(handler);
timer.schedule(mTask, 0, period);
}
public void cancel() {
if (mTask != null) {
mTask.cancel();
mTask = null;
}
}
class MyTask extends TimerTask {
private Handler handler;
public MyTask(Handler handler) {
this.handler = handler;
}
@Override
public void run() {
handler.obtainMessage().sendToTarget();
}
}
}
}