PullToRefreshGridView添加头部

原材料是PullToRefreshListView和一个带有添加head功能的GridView,然后稍微组装下就有了:

package com.project.eric.system.view;
/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import java.util.ArrayList;
import android.annotation.SuppressLint;
import android.content.Context;
import android.database.DataSetObservable;
import android.database.DataSetObserver;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.FrameLayout;
import android.widget.GridView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.WrapperListAdapter;
/**
 * A {@link GridView} that supports adding header rows in a
 * very similar way to {@link ListView}.
 * See {@link HeaderGridView#addHeaderView(View, Object, boolean)}
 */
@SuppressLint("NewApi")
public class HeaderGridView extends  GridView  {
    private static final String TAG = "HeaderGridView";
    /**
     * A class that represents a fixed view in a list, for example a header at the top
     * or a footer at the bottom.
     */
    private static class FixedViewInfo {
        /** The view to add to the grid */
        public View view;
        public ViewGroup viewContainer;
        /** The data backing the view. This is returned from {@link ListAdapter#getItem(int)}. */
        public Object data;
        /** true if the fixed view should be selectable in the grid */
        public boolean isSelectable;
    }
    private ArrayList mHeaderViewInfos = new ArrayList();
    private void initHeaderGridView() {
        super.setClipChildren(false);
    }
    public HeaderGridView(Context context) {
        super(context);
        initHeaderGridView();
    }
    public HeaderGridView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initHeaderGridView();
    }
    public HeaderGridView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initHeaderGridView();
    }
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        ListAdapter adapter = getAdapter();
        if (adapter != null && adapter instanceof HeaderViewGridAdapter) {
            ((HeaderViewGridAdapter) adapter).setNumColumns(getNumColumns());
        }
    }
    @Override
    public void setClipChildren(boolean clipChildren) {
        // Ignore, since the header rows depend on not being clipped
    }
    /**
     * Add a fixed view to appear at the top of the grid. If addHeaderView is
     * called more than once, the views will appear in the order they were
     * added. Views added using this call can take focus if they want.
     * 

* NOTE: Call this before calling setAdapter. This is so HeaderGridView can wrap * the supplied cursor with one that will also account for header views. * * @param v The view to add. * @param data Data to associate with this view * @param isSelectable whether the item is selectable */ public void addHeaderView(View v, Object data, boolean isSelectable) { ListAdapter adapter = getAdapter(); if (adapter != null && ! (adapter instanceof HeaderViewGridAdapter)) { throw new IllegalStateException( "Cannot add header view to grid -- setAdapter has already been called."); } FixedViewInfo info = new FixedViewInfo(); FrameLayout fl = new FullWidthFixedViewLayout(getContext()); fl.addView(v); info.view = v; info.viewContainer = fl; info.data = data; info.isSelectable = isSelectable; mHeaderViewInfos.add(info); // in the case of re-adding a header view, or adding one later on, // we need to notify the observer if (adapter != null) { ((HeaderViewGridAdapter) adapter).notifyDataSetChanged(); } } /** * Add a fixed view to appear at the top of the grid. If addHeaderView is * called more than once, the views will appear in the order they were * added. Views added using this call can take focus if they want. *

* NOTE: Call this before calling setAdapter. This is so HeaderGridView can wrap * the supplied cursor with one that will also account for header views. * * @param v The view to add. */ public void addHeaderView(View v) { addHeaderView(v, null, true); } public int getHeaderViewCount() { return mHeaderViewInfos.size(); } /** * Removes a previously-added header view. * * @param v The view to remove * @return true if the view was removed, false if the view was not a header * view */ public boolean removeHeaderView(View v) { if (mHeaderViewInfos.size() > 0) { boolean result = false; ListAdapter adapter = getAdapter(); if (adapter != null && ((HeaderViewGridAdapter) adapter).removeHeader(v)) { result = true; } removeFixedViewInfo(v, mHeaderViewInfos); return result; } return false; } private void removeFixedViewInfo(View v, ArrayList where) { int len = where.size(); for (int i = 0; i < len; ++i) { FixedViewInfo info = where.get(i); if (info.view == v) { where.remove(i); break; } } } @Override public void setAdapter(ListAdapter adapter) { if (mHeaderViewInfos.size() > 0) { HeaderViewGridAdapter hadapter = new HeaderViewGridAdapter(mHeaderViewInfos, adapter); int numColumns = getNumColumns(); if (numColumns > 1) { hadapter.setNumColumns(numColumns); } super.setAdapter(hadapter); } else { super.setAdapter(adapter); } } private class FullWidthFixedViewLayout extends FrameLayout { public FullWidthFixedViewLayout(Context context) { super(context); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int targetWidth = HeaderGridView.this.getMeasuredWidth() - HeaderGridView.this.getPaddingLeft() - HeaderGridView.this.getPaddingRight(); widthMeasureSpec = MeasureSpec.makeMeasureSpec(targetWidth, MeasureSpec.getMode(widthMeasureSpec)); super.onMeasure(widthMeasureSpec, heightMeasureSpec); } } /** * ListAdapter used when a HeaderGridView has header views. This ListAdapter * wraps another one and also keeps track of the header views and their * associated data objects. *

This is intended as a base class; you will probably not need to * use this class directly in your own code. */ private static class HeaderViewGridAdapter implements WrapperListAdapter, Filterable { // This is used to notify the container of updates relating to number of columns // or headers changing, which changes the number of placeholders needed private final DataSetObservable mDataSetObservable = new DataSetObservable(); private final ListAdapter mAdapter; private int mNumColumns = 1; // This ArrayList is assumed to NOT be null. ArrayList mHeaderViewInfos; boolean mAreAllFixedViewsSelectable; private final boolean mIsFilterable; public HeaderViewGridAdapter(ArrayList headerViewInfos, ListAdapter adapter) { mAdapter = adapter; mIsFilterable = adapter instanceof Filterable; if (headerViewInfos == null) { throw new IllegalArgumentException("headerViewInfos cannot be null"); } mHeaderViewInfos = headerViewInfos; mAreAllFixedViewsSelectable = areAllListInfosSelectable(mHeaderViewInfos); } public int getHeadersCount() { return mHeaderViewInfos.size(); } @Override public boolean isEmpty() { return (mAdapter == null || mAdapter.isEmpty()) && getHeadersCount() == 0; } public void setNumColumns(int numColumns) { if (numColumns < 1) { throw new IllegalArgumentException("Number of columns must be 1 or more"); } if (mNumColumns != numColumns) { mNumColumns = numColumns; notifyDataSetChanged(); } } private boolean areAllListInfosSelectable(ArrayList infos) { if (infos != null) { for (FixedViewInfo info : infos) { if (!info.isSelectable) { return false; } } } return true; } public boolean removeHeader(View v) { for (int i = 0; i < mHeaderViewInfos.size(); i++) { FixedViewInfo info = mHeaderViewInfos.get(i); if (info.view == v) { mHeaderViewInfos.remove(i); mAreAllFixedViewsSelectable = areAllListInfosSelectable(mHeaderViewInfos); mDataSetObservable.notifyChanged(); return true; } } return false; } @Override public int getCount() { if (mAdapter != null) { return getHeadersCount() * mNumColumns + mAdapter.getCount(); } else { return getHeadersCount() * mNumColumns; } } @Override public boolean areAllItemsEnabled() { if (mAdapter != null) { return mAreAllFixedViewsSelectable && mAdapter.areAllItemsEnabled(); } else { return true; } } @Override public boolean isEnabled(int position) { // Header (negative positions will throw an ArrayIndexOutOfBoundsException) int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns; if (position < numHeadersAndPlaceholders) { return (position % mNumColumns == 0) && mHeaderViewInfos.get(position / mNumColumns).isSelectable; } // Adapter final int adjPosition = position - numHeadersAndPlaceholders; int adapterCount = 0; if (mAdapter != null) { adapterCount = mAdapter.getCount(); if (adjPosition < adapterCount) { return mAdapter.isEnabled(adjPosition); } } throw new ArrayIndexOutOfBoundsException(position); } @Override public Object getItem(int position) { // Header (negative positions will throw an ArrayIndexOutOfBoundsException) int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns; if (position < numHeadersAndPlaceholders) { if (position % mNumColumns == 0) { return mHeaderViewInfos.get(position / mNumColumns).data; } return null; } // Adapter final int adjPosition = position - numHeadersAndPlaceholders; int adapterCount = 0; if (mAdapter != null) { adapterCount = mAdapter.getCount(); if (adjPosition < adapterCount) { return mAdapter.getItem(adjPosition); } } throw new ArrayIndexOutOfBoundsException(position); } @Override public long getItemId(int position) { int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns; if (mAdapter != null && position >= numHeadersAndPlaceholders) { int adjPosition = position - numHeadersAndPlaceholders; int adapterCount = mAdapter.getCount(); if (adjPosition < adapterCount) { return mAdapter.getItemId(adjPosition); } } return -1; } @Override public boolean hasStableIds() { if (mAdapter != null) { return mAdapter.hasStableIds(); } return false; } @Override public View getView(int position, View convertView, ViewGroup parent) { // Header (negative positions will throw an ArrayIndexOutOfBoundsException) int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns ; if (position < numHeadersAndPlaceholders) { View headerViewContainer = mHeaderViewInfos .get(position / mNumColumns).viewContainer; if (position % mNumColumns == 0) { return headerViewContainer; } else { if (convertView == null) { convertView = new View(parent.getContext()); } // We need to do this because GridView uses the height of the last item // in a row to determine the height for the entire row. convertView.setVisibility(View.INVISIBLE); convertView.setMinimumHeight(headerViewContainer.getHeight()); return convertView; } } // Adapter final int adjPosition = position - numHeadersAndPlaceholders; int adapterCount = 0; if (mAdapter != null) { adapterCount = mAdapter.getCount(); if (adjPosition < adapterCount) { return mAdapter.getView(adjPosition, convertView, parent); } } throw new ArrayIndexOutOfBoundsException(position); } @Override public int getItemViewType(int position) { int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns; if (position < numHeadersAndPlaceholders && (position % mNumColumns != 0)) { // Placeholders get the last view type number return mAdapter != null ? mAdapter.getViewTypeCount() : 1; } if (mAdapter != null && position >= numHeadersAndPlaceholders) { int adjPosition = position - numHeadersAndPlaceholders; int adapterCount = mAdapter.getCount(); if (adjPosition < adapterCount) { return mAdapter.getItemViewType(adjPosition); } } return AdapterView.ITEM_VIEW_TYPE_HEADER_OR_FOOTER; } @Override public int getViewTypeCount() { if (mAdapter != null) { return mAdapter.getViewTypeCount() + 1; } return 2; } @Override public void registerDataSetObserver(DataSetObserver observer) { mDataSetObservable.registerObserver(observer); if (mAdapter != null) { mAdapter.registerDataSetObserver(observer); } } @Override public void unregisterDataSetObserver(DataSetObserver observer) { mDataSetObservable.unregisterObserver(observer); if (mAdapter != null) { mAdapter.unregisterDataSetObserver(observer); } } @Override public Filter getFilter() { if (mIsFilterable) { return ((Filterable) mAdapter).getFilter(); } return null; } @Override public ListAdapter getWrappedAdapter() { return mAdapter; } public void notifyDataSetChanged() { mDataSetObservable.notifyChanged(); } } }

PullToRefreshGridView:

package com.project.eric.system.view;

/*******************************************************************************
 * Copyright 2011, 2012 Chris Banes.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
import android.annotation.TargetApi;
import android.content.Context;
import android.os.Build.VERSION;
import android.os.Build.VERSION_CODES;
import android.util.AttributeSet;
import android.view.View;

import com.handmark.pulltorefresh.library.OverscrollHelper;
import com.handmark.pulltorefresh.library.PullToRefreshAdapterViewBase;

import com.handmark.pulltorefresh.library.internal.EmptyViewMethodAccessor;
import com.project.eric.R;

public class PullToRefreshGridView extends PullToRefreshAdapterViewBase {

    public PullToRefreshGridView(Context context) {
        super(context);
    }

    public PullToRefreshGridView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public PullToRefreshGridView(Context context, Mode mode) {
        super(context, mode);
    }

    public PullToRefreshGridView(Context context, Mode mode, AnimationStyle style) {
        super(context, mode, style);
    }

    @Override
    public final Orientation getPullToRefreshScrollDirection() {
        return Orientation.VERTICAL;
    }

    @Override
    protected final HeaderGridView createRefreshableView(Context context, AttributeSet attrs) {
        final HeaderGridView gv;
        if (VERSION.SDK_INT >= VERSION_CODES.GINGERBREAD) {
            gv = new InternalGridViewSDK9(context, attrs);
        } else {
            gv = new InternalGridView(context, attrs);
        }

        // Use Generated ID (from res/values/ids.xml)
        gv.setId(R.id.gridview);
        return gv;
    }

    class InternalGridView extends HeaderGridView implements EmptyViewMethodAccessor {

        public InternalGridView(Context context, AttributeSet attrs) {
            super(context, attrs);
        }

        @Override
        public void setEmptyView(View emptyView) {
            PullToRefreshGridView.this.setEmptyView(emptyView);
        }

        @Override
        public void setEmptyViewInternal(View emptyView) {
            super.setEmptyView(emptyView);
        }
    }

    @TargetApi(9)
    final class InternalGridViewSDK9 extends InternalGridView {

        public InternalGridViewSDK9(Context context, AttributeSet attrs) {
            super(context, attrs);
        }

        @Override
        protected boolean overScrollBy(int deltaX, int deltaY, int scrollX, int scrollY, int scrollRangeX,
                                       int scrollRangeY, int maxOverScrollX, int maxOverScrollY, boolean isTouchEvent) {

            final boolean returnValue = super.overScrollBy(deltaX, deltaY, scrollX, scrollY, scrollRangeX,
                    scrollRangeY, maxOverScrollX, maxOverScrollY, isTouchEvent);

            // Does all of the hard work...
            OverscrollHelper.overScrollBy(PullToRefreshGridView.this, deltaX, scrollX, deltaY, scrollY, isTouchEvent);

            return returnValue;
        }
    }
}

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