自定義LoadMoreListView

自定義loadmoreListView 完成對數據的下滑加載，和 加載狀態的顯示的處理

模板代碼

package xiaoxu.com.lifeservice.ui.loadmore;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.widget.AbsListView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.RelativeLayout;
import android.widget.TextView;

import java.util.List;

import xiaoxu.com.lifeservice.R;
import xiaoxu.com.lifeservice.http.HttpClient;

/**
 * Created by Administrator on 2016/5/4.
 * 用法：和普通的listView一樣，在xml文件中指定，不過這裡應該指定為 LoadMoreListView
 * 提供了setmOnLoadMoreListener()公有的方法，接口回調機制，完成加載動作。
 * 注意：這裡的 HttpClient.PAGE_SIZE 是指該listView應該默認為加載多少條item的數量.
 *
 */
public class LoadMoreListView extends ListView implements AbsListView.OnScrollListener {

    Boolean mIsLoadingMore = false;
    Boolean mLastItemVisible;
    OnScrollListener mOnScrollListener;
    public OnLoadMoreListener mOnLoadMoreListener;
    RelativeLayout mFooterView;
    ProgressBar mProgressBar;
    TextView mTextView;

    public void setmOnScrollListener(OnScrollListener mOnScrollListener) {
        this.mOnScrollListener = mOnScrollListener;
    }


    public LoadMoreListView(Context context) {
        super(context);
        init();
    }

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

    public LoadMoreListView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    public LoadMoreListView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init();
    }

    private void init() {

        mFooterView = (RelativeLayout) LayoutInflater.from(getContext()).inflate(R.layout.layout_load_more, null, false);
        mProgressBar = (ProgressBar) mFooterView.findViewById(R.id.progress_bar);
        mTextView = (TextView) mFooterView.findViewById(R.id.text);

        removeFooterView(mFooterView);
        setFooterDividersEnabled(false);
        addFooterView(mFooterView);
        super.setOnScrollListener(this);
    }

    @Override
    public void setAdapter(ListAdapter adapter) {
        super.setAdapter(adapter);
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {

        if (!mIsLoadingMore && scrollState == OnScrollListener.SCROLL_STATE_IDLE && mLastItemVisible) {
            mIsLoadingMore = true;
            onLoadMore(); //加載一次數據  接口回調
        }
        if( mOnScrollListener != null ) {

            mOnScrollListener.onScrollStateChanged(view,scrollState);
        }
    }

    public void setmOnLoadMoreListener(OnLoadMoreListener mOnLoadMoreListener) {
        this.mOnLoadMoreListener = mOnLoadMoreListener;
    }

    private void onLoadMore() {
        if(mIsLoadingMore != null) {

            mOnLoadMoreListener.onLoadMore();
        }

    }

    /**
     * Set whether the Last Item is Visible. lastVisibleItemIndex is a
     * zero-based index, so we minus one totalItemCount to check
     */
    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {

        if (null != mOnLoadMoreListener) {
            mLastItemVisible = (totalItemCount > 0) && (firstVisibleItem + visibleItemCount >= totalItemCount - 1);
        }

        // Finally call OnScrollListener if we have one
        if (mOnScrollListener != null) {

            mOnScrollListener.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount);
        }

    }

    public void updateLoadMoreViewText (List data) {

        if(getAdapter().getCount() == 0 || data.isEmpty()) {

            setLoadMoreViewTextNoData();
        } else if (data.size() < HttpClient.PAGE_SIZE) {
            //每一頁要加載的item的數量，當最後一次加載的數據小於這個值後，設置以加載全部。
            setLoadMoreViewTextNoMoreData();

        }

        mIsLoadingMore = false;
    }


    public void onLoadMoreComplete(){

        mIsLoadingMore = false;
    }

    public void setLoadMoreViewTextError() {
        mTextView.setText("網絡異常，加載重試");
        mProgressBar.setVisibility(GONE);
        mIsLoadingMore = false;
    }

    public void setLoadMoreViewTextNoData() {
        mTextView.setText("暫無數據");
        mProgressBar.setVisibility(GONE);
        mIsLoadingMore = false;
    }

    public void setLoadMoreViewTextNoMoreData() {
        mTextView.setText("已加載全部");
        mProgressBar.setVisibility(GONE);
        mIsLoadingMore = false;
    }

    public void setLoadMoreViewText(String text) {
        mTextView.setText(text);
        mProgressBar.setVisibility(VISIBLE);
    }

    public void setLoadMoreViewText(int resId) {
        mTextView.setText(resId);
        mProgressBar.setVisibility(VISIBLE);
    }

    public interface OnLoadMoreListener {
       void onLoadMore();
    }

}

以下是該模板代碼用到的xml文件

    <relativelayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="40dp" android:clickable="false" android:gravity="center">

    <progressbar android:id="@+id/progress_bar" android:layout_width="30dp" android:layout_height="30dp" android:layout_centervertical="true" android:layout_gravity="center" android:layout_marginright="10dp" android:indeterminate="false">
    <textview android:id="@+id/text" android:layout_width="wrap_content" android:layout_height="60dp" android:layout_centerinparent="true" android:layout_torightof="@id/progress_bar" android:text="正在載入...." android:gravity="center" android:textappearance="?android:attr/textAppearanceSmall">

</textview></progressbar></relativelayout>
</code>

使用Demo

private void loadData() {
        if (isLoadAll) {

            return;
        }
        searchParam.setPno(pno);//SearchParam封裝的請求信息參數的類  如經緯度、城市...
        HttpClient.getRecommendShops(searchParam, new   HttpResponseHandle() {
//靜態方法回調
            @Override
            public void onSuccess(String content) {

                mPtrFrame.refreshComplete();
                JSONObject object = JSON.parseObject(content);
                List list = JSONArray.parseArray(object.getString("body"), SearchShop.class);

                for(SearchShop s : list) {

                    Log.v("TextFrag", "  name " + s.getName() + "\n");
                }
                Log.v("TextFrag","------");
                listView.updateLoadMoreViewText(list);

                isLoadAll = list.size() < HttpClient.PAGE_SIZE;

                Log.v("TextFrag","  listSize " + list.size());

                if (pno == 1) {
                    quickAdapter.clear();
                }
                quickAdapter.addAll(list);
                pno++;
            }

            @Override
            public void onFailure(Request request, IOException e) {
                mPtrFrame.refreshComplete();
            }
        });
    }

        listView.setmOnLoadMoreListener(new LoadMoreListView.OnLoadMoreListener() {
            @Override
            public void onLoadMore() {

                Log.v("TextFrag","加載更多");

                loadData();

            }
        });


        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView parent, View view, int position, long id) {

              //UiHelper.showHouseDetailActivity(mActivity);
            }
        });

總結: 這樣就完成了 向下滑動listView，執行加載操作。根據加載的狀況listview 底部顯示提醒信息。