package com.markupartist.android.widget;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import com.markupartist.android.example.pulltorefresh.R;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.view.animation.RotateAnimation;
import android.widget.AbsListView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.AbsListView.OnScrollListener;
public class PullToRefreshListView extends ListView implements OnScrollListener {
private static final int TAP_TO_REFRESH = 1;
private static final int PULL_TO_REFRESH = 2;
private static final int RELEASE_TO_REFRESH = 3;
private static final int REFRESHING = 4;
private static final String TAG = "PullToRefreshListView";
private OnRefreshListener mOnRefreshListener;
/**
* Listener that will receive notifications every time the list scrolls.
*/
private OnScrollListener mOnScrollListener;
private LayoutInflater mInflater;
private LinearLayout mRefreshView;
private TextView mRefreshViewText;
private ImageView mRefreshViewImage;
private ProgressBar mRefreshViewProgress;
private TextView mRefreshViewLastUpdated;
private int mCurrentScrollState;
private int mRefreshState;
private RotateAnimation mFlipAnimation;
private RotateAnimation mReverseFlipAnimation;
private int mRefreshViewHeight;
private int mRefreshOriginalTopPadding;
private int mLastMotionY;
public PullToRefreshListView(Context context) {
super(context);
init(context);
}
public PullToRefreshListView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public PullToRefreshListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
private void init(Context context) {
// Load all of the animations we need in code rather than through XML
mFlipAnimation = new RotateAnimation(0, -180,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
mFlipAnimation.setInterpolator(new LinearInterpolator());
mFlipAnimation.setDuration(250);
mFlipAnimation.setFillAfter(true);
mReverseFlipAnimation = new RotateAnimation(-180, 0,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
mReverseFlipAnimation.setInterpolator(new LinearInterpolator());
mReverseFlipAnimation.setDuration(250);
mReverseFlipAnimation.setFillAfter(true);
mInflater = (LayoutInflater) context.getSystemService(
Context.LAYOUT_INFLATER_SERVICE);
mRefreshView = (LinearLayout) mInflater.inflate(
R.layout.pull_to_refresh_header, null);
mRefreshViewText =
(TextView) mRefreshView.findViewById(R.id.pull_to_refresh_text);
mRefreshViewImage =
(ImageView) mRefreshView.findViewById(R.id.pull_to_refresh_image);
mRefreshViewProgress =
(ProgressBar) mRefreshView.findViewById(R.id.pull_to_refresh_progress);
mRefreshViewLastUpdated =
(TextView) mRefreshView.findViewById(R.id.pull_to_refresh_updated_at);
mRefreshViewImage.setMinimumHeight(50);
mRefreshView.setOnClickListener(new OnClickRefreshListener());
mRefreshOriginalTopPadding = mRefreshView.getPaddingTop();
mRefreshState = TAP_TO_REFRESH;
addHeaderView(mRefreshView);
super.setOnScrollListener(this);
measureView(mRefreshView);
mRefreshViewHeight = mRefreshView.getMeasuredHeight();
}
@Override
protected void onAttachedToWindow() {
setSelection(1);
}
@Override
public void setAdapter(ListAdapter adapter) {
super.setAdapter(adapter);
setSelection(1);
}
/**
* Set the listener that will receive notifications every time the list
* scrolls.
*
* @param l The scroll listener.
*/
@Override
public void setOnScrollListener(AbsListView.OnScrollListener l) {
mOnScrollListener = l;
}
/**
* Register a callback to be invoked when this list should be refreshed.
*
* @param onRefreshListener The callback to run.
*/
public void setOnRefreshListener(OnRefreshListener onRefreshListener) {
mOnRefreshListener = onRefreshListener;
}
/**
* Set a text to represent when the list was last updated.
* @param lastUpdated Last updated at.
*/
public void setLastUpdated(CharSequence lastUpdated) {
if (lastUpdated != null) {
mRefreshViewLastUpdated.setVisibility(View.VISIBLE);
mRefreshViewLastUpdated.setText(lastUpdated);
} else {
mRefreshViewLastUpdated.setVisibility(View.GONE);
}
}
private MotionEvent moveEvent;//记录move事件,只为resetHeader时知道当时的Y位置
@Override
public boolean onTouchEvent(MotionEvent event) {
final int y = (int) event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_UP:
if (!isVerticalScrollBarEnabled()) {
setVerticalScrollBarEnabled(true);
}
if (getFirstVisiblePosition() == 0 && mRefreshState != REFRESHING) {
if ((mRefreshView.getBottom() > mRefreshViewHeight
|| mRefreshView.getTop() >= 0)
&& mRefreshState == RELEASE_TO_REFRESH) {
// Initiate the refresh
mRefreshState = REFRESHING;
prepareForRefresh();
onRefresh();
} else if (mRefreshView.getBottom() < mRefreshViewHeight
|| mRefreshView.getTop() < 0) {
// Abort refresh and scroll down below the refresh view
resetHeader();
setSelection(1);
}
}
break;
case MotionEvent.ACTION_DOWN:
mLastMotionY = y;
break;
case MotionEvent.ACTION_MOVE:
moveEvent = event;
applyHeaderPadding(event);
break;
}
return super.onTouchEvent(event);
}
private void applyHeaderPadding(MotionEvent ev) {
final int historySize = ev.getHistorySize();
// Workaround for getPointerCount() which is unavailable in 1.5
// (it's always 1 in 1.5)
int pointerCount = 1;
try {
Method method = MotionEvent.class.getMethod("getPointerCount");
pointerCount = (Integer)method.invoke(ev);
} catch (NoSuchMethodException e) {
pointerCount = 1;
} catch (IllegalArgumentException e) {
throw e;
} catch (IllegalAccessException e) {
System.err.println("unexpected " + e);
} catch (InvocationTargetException e) {
System.err.println("unexpected " + e);
}
for (int h = 0; h < historySize; h++) {
for (int p = 0; p < pointerCount; p++) {
if (mRefre