Scrollfix for short list

pulltorefresh/default.properties

@@ -1,12 +1,3 @@
-# This file is automatically generated by Android Tools.
-# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
-# 
-# This file must be checked in Version Control Systems.
-# 
-# To customize properties used by the Ant build system use,
-# "build.properties", and override values to adapt the script to your
-# project structure.
-
-# Project target.
-target=android-10
 android.library=true
+# Project target.
+target=android-14

pulltorefresh/project.properties

@@ -0,0 +1,12 @@
+# This file is automatically generated by Android Tools.
+# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
+#
+# This file must be checked in Version Control Systems.
+#
+# To customize properties used by the Ant build system use,
+# "ant.properties", and override values to adapt the script to your
+# project structure.
+
+android.library=true
+# Project target.
+target=android-10

pulltorefresh/src/com/markupartist/android/widget/PullToRefreshListView.java

@@ -31,6 +31,7 @@ public class PullToRefreshListView extends ListView implements OnScrollListener
     private int mRefreshState = PULL_TO_REFRESH;
 
     private OnRefreshListener mOnRefreshListener;
+    private OnEndOfListReachedListener mOnEndOfListListener;
 
     /**
      * Listener that will receive notifications every time the list scrolls.
@@ -52,6 +53,7 @@ public class PullToRefreshListView extends ListView implements OnScrollListener
     private int mRefreshOriginalTopPadding;
     private int mLastMotionY;
     private int mHeight = -1;
+    private int mScrollPriorLast = -1;
 
     private boolean mBounceHack;
     private TextView mFooterView;
@@ -149,46 +151,89 @@ protected void onDraw(Canvas canvas) {
             adaptFooterHeight();
         }
     }
-
+    
     /**
-     * Adapts the height of the footer view.
+     * Sets list view selection to first element in adapter unless refreshing where it will set it to the refresh view element
      */
-    private void adaptFooterHeight() {
-        int itemHeight = getTotalItemHeight();
-        int footerAndHeaderSize = mFooterView.getHeight()
-            + (mRefreshViewHeight - mRefreshOriginalTopPadding);
-        int actualItemsSize = itemHeight - footerAndHeaderSize;
-        if (mHeight < actualItemsSize) {
-            mFooterView.setHeight(0);
-        } else {
-            int h = mHeight - actualItemsSize;
-            mFooterView.setHeight(h);
-            setSelection(1);
-        }
-    }
-
-    /**
-     * Calculates the combined height of all items in the adapter.
-     * 
-     * Modified from http://iserveandroid.blogspot.com/2011/06/how-to-calculate-lsitviews-total.html
-     * 
-     * @return 
-     */
-    private int getTotalItemHeight() {
-        ListAdapter adapter = getAdapter();
-        int listviewElementsheight = 0;
-        for(int i =0; i < adapter.getCount(); i++) {
-            View mView  = adapter.getView(i, null, this);
-            mView.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
-                    MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
-            listviewElementsheight+= mView.getMeasuredHeight();
-        }
-        return listviewElementsheight;
-    }
+	private void setSelectionToFirst() {
+		if (getAdapter() != null && mRefreshState != REFRESHING) {
+			// This allows for the divider to push the selection down from the top so the fading edge doesn't obscure the first view
+			setSelectionFromTop(1, getDividerHeight());
+		} else {
+			// Refreshing or no adapter, display the refresh view
+			super.setSelection(0);
+		}
+	}
+
+	@Override
+	public void setSelection(int position) {
+		// If the 0th or 1st element do special behavior
+		if (position <= 1) {
+			setSelectionToFirst();
+		} else {
+			// Force to index 0 while refreshing, allow other indices while not
+			super.setSelection((mRefreshState == REFRESHING) ? 0 : position);
+		}
+	}
+
+	/**
+	 * Adapts the height of the footer view.
+	 */
+	private void adaptFooterHeight() {
+		if (mHeight == -1) {
+			return;
+		}
+		// We can fill up to the total height - header padding to get it off screen
+		int spaceToFill = mHeight - mRefreshOriginalTopPadding;
+		int itemHeight = getTotalItemHeight(spaceToFill);
+		spaceToFill -= itemHeight;
+
+		if (spaceToFill <= 0) {
+			mFooterView.setHeight(0);
+		} else {
+			mFooterView.setHeight(spaceToFill);
+			setSelectionToFirst();
+		}
+	}
+
+	/**
+	 * Calculates the combined height of all items in the adapter. Does not look at header and footer
+	 * 
+	 * Modified from
+	 * http://iserveandroid.blogspot.com/2011/06/how-to-calculate-lsitviews-total.html
+	 * 
+	 * @param spaceToFill
+	 *            the maximum item height we care about
+	 * @return total item height, capped to spaceToFill
+	 */
+	private int getTotalItemHeight(int spaceToFill) {
+		ListAdapter adapter = getAdapter();
+		// If no adapter there is no item height
+		if (adapter == null) {
+			return 0;
+		}
+		int listviewElementsheight = 0;
+		// Need to constrain width for lists with variable height items or items with wrapping text
+		int desiredWidth = MeasureSpec.makeMeasureSpec(getWidth(),
+				MeasureSpec.AT_MOST);
+		// Skip header and footer
+		for (int i = 1; i < adapter.getCount() - 1
+				&& listviewElementsheight < spaceToFill; i++) {
+			View mView = adapter.getView(i, null, this);
+			mView.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);
+			listviewElementsheight += mView.getMeasuredHeight();
+		}
+		// Add in dividers
+		listviewElementsheight += getDividerHeight() * (adapter.getCount() - 1);
+		if (listviewElementsheight > spaceToFill) {
+			listviewElementsheight = spaceToFill;
+		}
+		return listviewElementsheight;
+	}
 
     @Override
     protected void onAttachedToWindow() {
-        setSelection(1);
+    	setSelectionToFirst();
     }
 
     @Override
@@ -198,8 +243,11 @@ public void setAdapter(ListAdapter adapter) {
         }
 
         super.setAdapter(adapter);
-
-        setSelection(1);
+        // Ensure with new data the view is reinitialized to beginning
+        setSelectionToFirst();
+        // With different data we may need to adjust footer height
+		adaptFooterHeight();
+		mScrollPriorLast = -1;
     }
 
     /**
@@ -221,6 +269,15 @@ public void setOnScrollListener(AbsListView.OnScrollListener l) {
     public void setOnRefreshListener(OnRefreshListener onRefreshListener) {
         mOnRefreshListener = onRefreshListener;
     }
+
+    /**
+     * Register a callback to be invoked when the end of the list is reached.
+     * 
+     * @param onEndOfListListener The callback to run.
+     */
+    public void setOnEndOfListReachedListener(OnEndOfListReachedListener onEndOfListListener) {
+    	mOnEndOfListListener = onEndOfListListener;
+    }
 
     /**
      * Set a text to represent when the list was last updated. 
@@ -256,7 +313,7 @@ public boolean onTouchEvent(MotionEvent event) {
                             || mRefreshView.getTop() <= 0) {
                         // Abort refresh and scroll down below the refresh view
                         resetHeader();
-                        setSelection(1);
+                        setSelectionToFirst();
                     }
                 }
                 break;
@@ -346,7 +403,6 @@ private void measureView(View child) {
         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
@@ -376,10 +432,26 @@ public void onScroll(AbsListView view, int firstVisibleItem,
         } else if (mCurrentScrollState == SCROLL_STATE_FLING
                 && firstVisibleItem == 0
                 && mRefreshState != REFRESHING) {
-            setSelection(1);
+        	setSelectionToFirst();
             mBounceHack = true;
         } else if (mBounceHack && mCurrentScrollState == SCROLL_STATE_FLING) {
-            setSelection(1);
+        	setSelectionToFirst();
+        }
+
+        if(mOnEndOfListListener != null)
+        {
+        	// what is the bottom item that is visible
+        	int lastInScreen = firstVisibleItem + visibleItemCount;
+
+        	// is the bottom item visible
+        	if (lastInScreen == totalItemCount) {
+        		// Only do callback 1x when we reach the bottom
+        		if (mScrollPriorLast != lastInScreen) {
+        			mScrollPriorLast = lastInScreen;
+        			// Do end of list reached callback
+        			mOnEndOfListListener.onEndOfListReached();
+        		}
+        	}
         }
 
         if (mOnScrollListener != null) {
@@ -388,7 +460,6 @@ public void onScroll(AbsListView view, int firstVisibleItem,
         }
     }
 
-    @Override
     public void onScrollStateChanged(AbsListView view, int scrollState) {
         mCurrentScrollState = scrollState;
 
@@ -440,7 +511,7 @@ public void onRefreshComplete() {
         // the next item.
         if (mRefreshView.getBottom() > 0) {
             invalidateViews();
-            setSelection(1);
+            setSelectionToFirst();
         }
     }
 
@@ -450,8 +521,6 @@ public void onRefreshComplete() {
      * list.
      */
     private class OnClickRefreshListener implements OnClickListener {
-
-        @Override
         public void onClick(View v) {
             if (mRefreshState != REFRESHING) {
                 prepareForRefresh();
@@ -474,4 +543,15 @@ public interface OnRefreshListener {
          */
         public void onRefresh();
     }
+
+    /**
+     * Interface definition for a callback to be invoked when end of list is reached.
+     */
+    public interface OnEndOfListReachedListener {
+        /**
+         * Called 1x when the end of list is reached. This might be used to implement an endless list which auto-loads more data as users scroll.
+         * It will only be called again if the adapter changes or the list grows/shrinks
+         */
+        public void onEndOfListReached();
+    }
 }

pulltorefreshexample/default.properties

@@ -1,12 +1,3 @@
-# This file is automatically generated by Android Tools.
-# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
-# 
-# This file must be checked in Version Control Systems.
-# 
-# To customize properties used by the Ant build system use,
-# "build.properties", and override values to adapt the script to your
-# project structure.
-
-# Project target.
-target=android-10
 android.library.reference.1=../pulltorefresh/
+# Project target.
+target=android-14

pulltorefreshexample/project.properties

@@ -0,0 +1,12 @@
+# This file is automatically generated by Android Tools.
+# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
+#
+# This file must be checked in Version Control Systems.
+#
+# To customize properties used by the Ant build system use,
+# "ant.properties", and override values to adapt the script to your
+# project structure.
+
+android.library.reference.1=../pulltorefresh/
+# Project target.
+target=android-10

pulltorefreshexample/src/com/markupartist/android/example/pulltorefresh/PullToRefreshActivity.java

@@ -9,8 +9,10 @@
 import android.view.View;
 import android.widget.ArrayAdapter;
 import android.widget.ListView;
+import android.widget.Toast;
 
 import com.markupartist.android.widget.PullToRefreshListView;
+import com.markupartist.android.widget.PullToRefreshListView.OnEndOfListReachedListener;
 import com.markupartist.android.widget.PullToRefreshListView.OnRefreshListener;
 
 public class PullToRefreshActivity extends ListActivity {    
@@ -25,12 +27,17 @@ public void onCreate(Bundle savedInstanceState) {
         // Set a listener to be invoked when the list should be refreshed.
         PullToRefreshListView listView = (PullToRefreshListView) getListView();
         listView.setOnRefreshListener(new OnRefreshListener() {
-            @Override
             public void onRefresh() {
                 // Do work to refresh the list here.
                 new GetRobotTalkTask().execute();
             }
         });
+        listView.setOnEndOfListReachedListener(new OnEndOfListReachedListener() {
+            public void onEndOfListReached() {
+                // Post a toast, could load more data here to extend the list
+                Toast.makeText(getApplicationContext(), "End of list reached", Toast.LENGTH_SHORT).show();
+            }
+        });
 
         mAdapter = new ArrayAdapter<String>(this,
                 android.R.layout.simple_list_item_1,