下拉刷新上拉加载+左滑编辑、删除等

最近忙着赶项目，忙了将近两个星期了，总算是有了空闲的时间，来新增一篇。这次最重要的功能就是<b>下拉刷新上拉加载+左滑编辑、删除</b>了，现在实现的方式很多,比如recyclerview+SwipeRefreshLayout，这需要加新的兼容包，所以我想在已有包的基础上修改，查了下项目中正好有PullToRefreshListView和SwipeMenuListView。就此开始调查合并之路。

调查

调查之后还是有挺多的资料的。最好用的如下实现

public class SwipeMenuPullToRefreshListView extends 
    PullToRefreshAdapterViewBase<SwipeMenuListView>
```
###实现代码
代码挺长的，如下
````java
public class SwipeMenuPullToRefreshListView extends 
    PullToRefreshAdapterViewBase<SwipeMenuListView>{
    
    private LoadingLayout mHeaderLoadingView;
    private LoadingLayout mFooterLoadingView;

    private FrameLayout mLvFooterLoadingFrame;
    // 轮播广告区域
    private View interceptView;
    private boolean mListViewExtrasEnabled;

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

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

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

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

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

    public void setInterceptView(View interceptView) {
        SwipeMenuPullToRefreshListView.this.interceptView = interceptView;
    }

    @Override
    protected void onRefreshing(final boolean doScroll) {
        /**
         * If we're not showing the Refreshing view, or the list is empty, the
         * the header/footer views won't show so we use the normal method.
         */
        ListAdapter adapter = getRefreshableView().getAdapter();
        if (!mListViewExtrasEnabled || !getShowViewWhileRefreshing()
                || null == adapter || adapter.isEmpty()) {
            super.onRefreshing(doScroll);
            return;
        }

        super.onRefreshing(false);

        final LoadingLayout origLoadingView, listViewLoadingView, oppositeListViewLoadingView;
        final int selection, scrollToY;

        switch (getCurrentMode()) {
        case MANUAL_REFRESH_ONLY:
        case PULL_FROM_END:
            origLoadingView = getFooterLayout();
            listViewLoadingView = mFooterLoadingView;
            oppositeListViewLoadingView = mHeaderLoadingView;
            selection = getRefreshableView().getCount() - 1;
            scrollToY = getScrollY() - getFooterSize();
            break;
        case PULL_FROM_START:
        default:
            origLoadingView = getHeaderLayout();
            listViewLoadingView = mHeaderLoadingView;
            oppositeListViewLoadingView = mFooterLoadingView;
            selection = 0;
            scrollToY = getScrollY() + getHeaderSize();
            break;
        }

        // Hide our original Loading View
        origLoadingView.reset();
        origLoadingView.hideAllViews();

        // Make sure the opposite end is hidden too
        oppositeListViewLoadingView.setVisibility(View.GONE);

        // Show the ListView Loading View and set it to refresh.
        listViewLoadingView.setVisibility(View.VISIBLE);
        listViewLoadingView.refreshing();

        if (doScroll) {
            // We need to disable the automatic visibility changes for now
            disableLoadingLayoutVisibilityChanges();

            // We scroll slightly so that the ListView's header/footer is at the
            // same Y position as our normal header/footer
            setHeaderScroll(scrollToY);

            // Make sure the ListView is scrolled to show the loading
            // header/footer
            getRefreshableView().setSelection(selection);

            // Smooth scroll as normal
            smoothScrollTo(0);
        }
    }

    @Override
    protected void onReset() {
        /**
         * If the extras are not enabled, just call up to super and return.
         */
        if (!mListViewExtrasEnabled) {
            super.onReset();
            return;
        }

        final LoadingLayout originalLoadingLayout, listViewLoadingLayout;
        final int scrollToHeight, selection;
        final boolean scrollLvToEdge;

        switch (getCurrentMode()) {
        case MANUAL_REFRESH_ONLY:
        case PULL_FROM_END:
            originalLoadingLayout = getFooterLayout();
            listViewLoadingLayout = mFooterLoadingView;
            selection = getRefreshableView().getCount() - 1;
            scrollToHeight = getFooterSize();
            scrollLvToEdge = Math.abs(getRefreshableView().getLastVisiblePosition()
                    - selection) <= 1;
            break;
        case PULL_FROM_START:
        default:
            originalLoadingLayout = getHeaderLayout();
            listViewLoadingLayout = mHeaderLoadingView;
            scrollToHeight = -getHeaderSize();
            selection = 0;
            scrollLvToEdge = Math.abs(getRefreshableView()
                    .getFirstVisiblePosition() - selection) <= 1;
            break;
        }

        // If the ListView header loading layout is showing, then we need to
        // flip so that the original one is showing instead
        if (listViewLoadingLayout.getVisibility() == View.VISIBLE) {

            // Set our Original View to Visible
            originalLoadingLayout.showInvisibleViews();

            // Hide the ListView Header/Footer
            listViewLoadingLayout.setVisibility(View.GONE);

            /**
             * Scroll so the View is at the same Y as the ListView
             * header/footer, but only scroll if: we've pulled to refresh, it's
             * positioned correctly
             */
            if (scrollLvToEdge && getState() != State.MANUAL_REFRESHING) {
                getRefreshableView().setSelection(selection);
                setHeaderScroll(scrollToHeight);
            }
        }

        // Finally, call up to super
        super.onReset();
    }

    @Override
    protected LoadingLayoutProxy createLoadingLayoutProxy(
            final boolean includeStart, final boolean includeEnd) {
        LoadingLayoutProxy proxy = super.createLoadingLayoutProxy(includeStart,
                includeEnd);

        if (mListViewExtrasEnabled) {
            final Mode mode = getMode();

            if (includeStart && mode.showHeaderLoadingLayout()) {
                proxy.addLayout(mHeaderLoadingView);
            }
            if (includeEnd && mode.showFooterLoadingLayout()) {
                proxy.addLayout(mFooterLoadingView);
            }
        }

        return proxy;
    }

    protected SwipeMenuListView createListView(Context context, AttributeSet attrs) {
        final SwipeMenuListView lv;
        if (VERSION.SDK_INT >= VERSION_CODES.GINGERBREAD) {
            lv = new InternalListViewSDK9(context, attrs);
        } else {
            lv = new InternalListView(context, attrs);
        }
        return lv;
    }

    @Override
    protected SwipeMenuListView createRefreshableView(Context context, AttributeSet attrs) {
        SwipeMenuListView lv = createListView(context, attrs);

        // Set it to this so it can be used in ListActivity/ListFragment
        lv.setId(android.R.id.list);
        return lv;
    }

    @Override
    protected void handleStyledAttributes(TypedArray a) {
        super.handleStyledAttributes(a);

        mListViewExtrasEnabled = a.getBoolean(
                R.styleable.PullToRefresh_ptrListViewExtrasEnabled, true);

        if (mListViewExtrasEnabled) {
            final FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
                    FrameLayout.LayoutParams.MATCH_PARENT,
                    FrameLayout.LayoutParams.WRAP_CONTENT,
                    Gravity.CENTER_HORIZONTAL);

            // Create Loading Views ready for use later
            FrameLayout frame = new FrameLayout(getContext());
            mHeaderLoadingView = createLoadingLayout(getContext(),
                    Mode.PULL_FROM_START, a);
            mHeaderLoadingView.setVisibility(View.GONE);
            frame.addView(mHeaderLoadingView, lp);
            getRefreshableView().addHeaderView(frame, null, false);

            mLvFooterLoadingFrame = new FrameLayout(getContext());
            mFooterLoadingView = createLoadingLayout(getContext(),
                    Mode.PULL_FROM_END, a);
            mFooterLoadingView.setVisibility(View.GONE);
            mLvFooterLoadingFrame.addView(mFooterLoadingView, lp);

            /**
             * If the value for Scrolling While Refreshing hasn't been
             * explicitly set via XML, enable Scrolling While Refreshing.
             */
            if (!a.hasValue(R.styleable.PullToRefresh_ptrScrollingWhileRefreshingEnabled)) {
                setScrollingWhileRefreshingEnabled(true);
            }
        }
    }

    @TargetApi(9)
    final class InternalListViewSDK9 extends InternalListView {

        public InternalListViewSDK9(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(SwipeMenuPullToRefreshListView.this, deltaX,
                    scrollX, deltaY, scrollY, isTouchEvent);

            return returnValue;
        }
    }

    protected class InternalListView extends SwipeMenuListView implements
            EmptyViewMethodAccessor {

        private boolean mAddedLvFooter = false;

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

        @Override
        protected void dispatchDraw(Canvas canvas) {
            /**
             * This is a bit hacky, but Samsung's ListView has got a bug in it
             * when using Header/Footer Views and the list is empty. This masks
             * the issue so that it doesn't cause an FC. See Issue #66.
             */
            try {
                super.dispatchDraw(canvas);
            } catch (IndexOutOfBoundsException e) {
                e.printStackTrace();
            }
        }

        @Override
        public boolean onInterceptTouchEvent(MotionEvent ev) {
            // 处理特定区域 拦截 Touch
            if (interceptView != null) {
                float px = ev.getRawX();
                float py = ev.getRawY();

                Rect winRect = new Rect();
                int[] l = new int[2];
                interceptView.getLocationOnScreen(l);
                winRect.set(l[0], l[1], l[0] + interceptView.getWidth(), l[1]
                        + interceptView.getHeight());
                if (px < winRect.right && px > winRect.left
                        && py < winRect.bottom && py > winRect.top) {
                    return false;
                }
            }
            return super.onInterceptTouchEvent(ev);
        }

        @Override
        public boolean dispatchTouchEvent(MotionEvent ev) {
            /**
             * This is a bit hacky, but Samsung's ListView has got a bug in it
             * when using Header/Footer Views and the list is empty. This masks
             * the issue so that it doesn't cause an FC. See Issue #66.
             */
            try {
                return super.dispatchTouchEvent(ev);
            } catch (IndexOutOfBoundsException e) {
                e.printStackTrace();
                return false;
            }
        }

        @Override
        public void setAdapter(ListAdapter adapter) {
            // Add the Footer View at the last possible moment
            if (null != mLvFooterLoadingFrame && !mAddedLvFooter) {
                addFooterView(mLvFooterLoadingFrame, null, false);
                mAddedLvFooter = true;
            }

            super.setAdapter(adapter);
        }

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

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

    }
}
```
除了这部分修改外我们还需要处理一下SwipeMenuListView ，把以下代码注释了，这里注释了对于嵌套ScrollView会有问题。
```java
//  @Override  //为与PullToRefresh一起用
//  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
//      // TODO Auto-generated method stub
//      int heightSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
//              MeasureSpec.AT_MOST);
//      super.onMeasure(widthMeasureSpec, heightSpec);
//  }
```
以上处理后就能轻松实现下拉刷新上拉加载+左滑编辑删除。
###附
如果需要对SwipeMenuListView 特定Item不用左滑，那么可以在getView中的createMenu(menu);代码进行判断处理