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package com.markupartist.android.widget; 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.ListAdapter; import android.widget.ListView; import android.widget.ProgressBar; import android.widget.RelativeLayout; import android.widget.TextView; import android.widget.AbsListView.OnScrollListener; import com.markupartist.android.widget.pulltorefresh.R; 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 RelativeLayout 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;     private boolean mBounceHack;     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 = (RelativeLayout) mInflater.inflate( R.layout.pull_to_refresh_header, this, false);         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() {         super.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);         }     }     @Override     public boolean onTouchEvent(MotionEvent event) {         final int y = (int) event.getY();         mBounceHack = false;         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:                 applyHeaderPadding(event);                 break;         }         return super.onTouchEvent(event);     }     private void applyHeaderPadding(MotionEvent ev) {         // getHistorySize has been available since API 1         int pointerCount = ev.getHistorySize();         for (int p = 0; p < pointerCount; p++) {             if (mRefreshState == RELEASE_TO_REFRESH) {                 if (isVerticalFadingEdgeEnabled()) {                     setVerticalScrollBarEnabled(false);                 }                 int historicalY = (int) ev.getHistoricalY(p);                 // Calculate the padding to apply, we divide by 1.7 to                 // simulate a more resistant effect during pull.                 int topPadding = (int) (((historicalY - mLastMotionY)                         - mRefreshViewHeight) / 1.7);                 mRefreshView.setPadding(                         mRefreshView.getPaddingLeft(),                         topPadding,                         mRefreshView.getPaddingRight(),                         mRefreshView.getPaddingBottom());             }         }     }     /**      * Sets the header padding back to original size.      */     private void resetHeaderPadding() {         mRefreshView.setPadding(                 mRefreshView.getPaddingLeft(),                 mRefreshOriginalTopPadding,                 mRefreshView.getPaddingRight(),                 mRefreshView.getPaddingBottom());     }     /**      * Resets the header to the original state.      */     private void resetHeader() {         if (mRefreshState != TAP_TO_REFRESH) {             mRefreshState = TAP_TO_REFRESH;             resetHeaderPadding();             // Set refresh view text to the pull label             mRefreshViewText.setText(R.string.pull_to_refresh_tap_label);             // Replace refresh drawable with arrow drawable             mRefreshViewImage.setImageResource(R.drawable.ic_pulltorefresh_arrow);             // Clear the full rotation animation             mRefreshViewImage.clearAnimation();             // Hide progress bar and arrow.             mRefreshViewImage.setVisibility(View.GONE);             mRefreshViewProgress.setVisibility(View.GONE);         }     }     private void measureView(View child) {         ViewGroup.LayoutParams p = child.getLayoutParams();         if (p == null) {             p = new ViewGroup.LayoutParams(                     ViewGroup.LayoutParams.FILL_PARENT,                     ViewGroup.LayoutParams.WRAP_CONTENT);         }         int childWidthSpec = ViewGroup.getChildMeasureSpec(0,                 0 + 0, p.width);         int lpHeight = p.height;         int childHeightSpec;         if (lpHeight > 0) {             childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight, MeasureSpec.EXACTLY);         } else {             childHeightSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);         }         child.measure(childWidthSpec, childHeightSpec);     }     @Override     public void onScroll(AbsListView view, int firstVisibleItem,             int visibleItemCount, int totalItemCount) {         // When the refresh view is completely visible, change the text to say         // "Release to refresh..." and flip the arrow drawable.         if (mCurrentScrollState == SCROLL_STATE_TOUCH_SCROLL                 && mRefreshState != REFRESHING) {             if (firstVisibleItem == 0) {                 mRefreshViewImage.setVisibility(View.VISIBLE);                 if ((mRefreshView.getBottom() >= mRefreshViewHeight + 20                         || mRefreshView.getTop() >= 0)                         && mRefreshState != RELEASE_TO_REFRESH) {                     mRefreshViewText.setText(R.string.pull_to_refresh_release_label);                     mRefreshViewImage.clearAnimation();                     mRefreshViewImage.startAnimation(mFlipAnimation);                     mRefreshState = RELEASE_TO_REFRESH;                 } else if (mRefreshView.getBottom() < mRefreshViewHeight + 20                         && mRefreshState != PULL_TO_REFRESH) {                     mRefreshViewText.setText(R.string.pull_to_refresh_pull_label);                     if (mRefreshState != TAP_TO_REFRESH) {                         mRefreshViewImage.clearAnimation();                         mRefreshViewImage.startAnimation(mReverseFlipAnimation);                     }                     mRefreshState = PULL_TO_REFRESH;                 }             } else {                 mRefreshViewImage.setVisibility(View.GONE);                 resetHeader();             }         } else if (mCurrentScrollState == SCROLL_STATE_FLING                 && firstVisibleItem == 0                 && mRefreshState != REFRESHING) {             setSelection(1);             mBounceHack = true;         } else if (mBounceHack && mCurrentScrollState == SCROLL_STATE_FLING) {             setSelection(1);         }         if (mOnScrollListener != null) {             mOnScrollListener.onScroll(view, firstVisibleItem,                     visibleItemCount, totalItemCount);         }     }     @Override     public void onScrollStateChanged(AbsListView view, int scrollState) {         mCurrentScrollState = scrollState;         if (mCurrentScrollState == SCROLL_STATE_IDLE) {             mBounceHack = false;         }         if (mOnScrollListener != null) {             mOnScrollListener.onScrollStateChanged(view, scrollState);         }     }     public void prepareForRefresh() {         resetHeaderPadding();         mRefreshViewImage.setVisibility(View.GONE);         // We need this hack, otherwise it will keep the previous drawable.         mRefreshViewImage.setImageDrawable(null);         mRefreshViewProgress.setVisibility(View.VISIBLE);         // Set refresh view text to the refreshing label         mRefreshViewText.setText(R.string.pull_to_refresh_refreshing_label);         mRefreshState = REFRESHING;     }     public void onRefresh() {         Log.d(TAG, "onRefresh");         if (mOnRefreshListener != null) {             mOnRefreshListener.onRefresh();         }     }     /**      * Resets the list to a normal state after a refresh.      * @param lastUpdated Last updated at.      */     public void onRefreshComplete(CharSequence lastUpdated) {         setLastUpdated(lastUpdated);         onRefreshComplete();     }     /**      * Resets the list to a normal state after a refresh.      */     public void onRefreshComplete() {                 Log.d(TAG, "onRefreshComplete");         resetHeader();         // If refresh view is visible when loading completes, scroll down to         // the next item.         if (mRefreshView.getBottom() > 0) {             invalidateViews();             setSelection(1);         }     }     /**      * Invoked when the refresh view is clicked on. This is mainly used when      * there's only a few items in the list and it's not possible to drag the      * list.      */     private class OnClickRefreshListener implements OnClickListener {         @Override         public void onClick(View v) {             if (mRefreshState != REFRESHING) {                 prepareForRefresh();                 onRefresh();             }         }     }     /**      * Interface definition for a callback to be invoked when list should be      * refreshed.      */     public interface OnRefreshListener {         /**          * Called when the list should be refreshed.          * <p>          * A call to {@link PullToRefreshListView #onRefreshComplete()} is          * expected to indicate that the refresh has completed.          */         public void onRefresh();     }

}

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