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ListView 巢狀 GridView 大法

起因

專案需求要用表格形式實現佈局
但是!!!需要下拉和上拉載入資料。
因為專案裡只有github裡的XListView改造的ListView,又因為本人太笨太懶,不想寫上拉下來gridview。。

廢話不多說

效果圖

1、定義一個主檢視 listview.xml

<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/listview"
    android:layout_width="match_parent"
    android:layout_height
="match_parent" android:clipToPadding="false" android:divider="@null" android:dividerHeight="10dp" android:padding="10dp">
</ListView>

就這樣,因為本例講的是listview巢狀gridview,不涉及上拉下拉,所以就用普通的listview咯

2、自定義GridView—NoScrollGridView

其實不自定義也行,當時為了防止gridview顯示補全blabla的,還是寫一個保證萬無一失。

public
class NoScrollGridView extends GridView { public NoScrollGridView(Context context, AttributeSet attrs) { super(context, attrs); } public NoScrollGridView(Context context) { super(context); } public NoScrollGridView(Context context, AttributeSet attrs, int defStyle) { super
(context, attrs, defStyle); } public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { //核心在此 int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST); super.onMeasure(widthMeasureSpec, expandSpec+50); } }

3、定義ListView單項佈局 listview_item.xml

<?xml version="1.0" encoding="utf-8"?>
<com.example.shen.sample.NoScrollGridView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/gridview"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:numColumns="2"
    android:stretchMode="columnWidth"
    android:horizontalSpacing="10dp"
    android:verticalSpacing="10dp" />
<!-- 注意
android:numColumns="2"
android:stretchMode="columnWidth"
-->

4、定義GridView單項佈局 gridview_item.xml

<?xml version="1.0" encoding="utf-8"?>
<ImageView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:id="@+id/imageview"
    android:background="#000"
    android:layout_height="80dp" />

5、定義GridView的資料介面卡 GridViewAdapter.java

/**
 * Created by Shen on 2015/10/29.
 * 普通的介面卡
 */
public class GridViewAdapter extends BaseAdapter {

    //資料來源
    private List<MainActivity.Bean> mList = new ArrayList<>();

    private Context mContext;

    public GridViewAdapter(Context context) {
        super();
        this.mContext = context;
    }

    public List<MainActivity.Bean> getmList() {
        return mList;
    }

    public void setmList(List<MainActivity.Bean> mList) {
        this.mList = mList;
    }

    @Override
    public int getCount() {
        return mList.size();
    }

    @Override
    public MainActivity.Bean getItem(int position) {
        return mList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            convertView = LayoutInflater.from(mContext).inflate(R.layout.gridview_item, parent, false);
            holder = new ViewHolder(convertView);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }
        //設定圖片內容,本例木有圖片
//        holder.iv.setImageResource(getItem(position));
        return convertView;
    }

    class ViewHolder {

        ImageView iv;

        public ViewHolder(View view) {
            iv = (ImageView) view.findViewById(R.id.imageview);
            view.setTag(this);
        }
    }
}

6、定義ListView的資料介面卡 ListViewAdapter.java

/**
 * Created by Shen on 2015/10/29.
 * ListView的資料來源
 * 在這裡給gridview設定資料
 * 重要
 */
public class ListViewAdapter extends BaseAdapter {

    //資料來源
    private List<MainActivity.Bean> mList = new ArrayList<>();

    //列數
    private int mColumn = 2;

    private Context mContext;

    public ListViewAdapter(Context context, List<MainActivity.Bean> list) {
        super();
        this.mContext = context;
        this.mList = list;
    }

    /**
     * 這部很重要
     *(核心)
     * @return listview的行數
     */
    @Override
    public int getCount() {
        int count = mList.size() / mColumn;
        if (mList.size() % mColumn > 0) {
            count++;
        }
        return count;
    }

    @Override
    public MainActivity.Bean getItem(int position) {
        return mList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            convertView = LayoutInflater.from(mContext).inflate(R.layout.listview_item, parent, false);
            holder = new ViewHolder(convertView);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        //定義gridView的資料來源
        List<MainActivity.Bean> list = new ArrayList<>();

        //根據列數,將資料塞進去(核心)
        for (int i = 0; i < mColumn; i++) {
            int n = position * mColumn + i;
            if (n < mList.size()) {
                list.add(getItem(n));
            }
        }

        //更新資料來源(核心)
        holder.adapter.setmList(list);
        holder.adapter.notifyDataSetChanged();
        return convertView;
    }

    class ViewHolder {

        GridView gridView;
        GridViewAdapter adapter;

        public ViewHolder(View view) {

            gridView = (GridView) view.findViewById(R.id.gridview);
            //將adapter定義在此,優化滑動效果(核心)
            adapter = new GridViewAdapter(mContext);
            //在此設定介面卡,資料來源在getView中新增(核心)
            gridView.setAdapter(adapter);

            view.setTag(this);
        }
    }
}

最後MainActivity.java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.listview);

        ListView listview = (ListView) findViewById(R.id.listview);
        List<Bean> list = new ArrayList();
        for (int i = 0; i < 19; i++) {
            list.add(new Bean());
        }
        ListViewAdapter adapter = new ListViewAdapter(this, list);
        listview.setAdapter(adapter);
    }

    public static class Bean {

    }
}

大功告成!

這裡寫圖片描述