如何使用Horizo​​ntal ListView根据CustomAdapter的getView中的位置获取图像

Question

我使用Horizo​​ntal Listview在适合的屏幕上显示四个图像，这样这些图像将从数据库中获取。

我的main.xml如下

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <com.test.hlistview.HorizListview
        android:id="@+id/hlvSimpleList"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

MainActivity类如下

public class MainActivity extends Activity {
    HorizListview hlist;
    private int[] imageid = new int[] { R.drawable.lion, R.drawable.love,
            R.drawable.android, R.drawable.handshake };
    private String[] imagename = new String[] { "Lion", "Love", "Android",
            "Handshake" };
    List<Details> additems;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        hlist = (HorizListview) findViewById(R.id.hlvSimpleList);
        additems = new ArrayList<Details>();
        Log.i("Length of array", "size is" + imagename.length);
        int length = imagename.length;

        for (int i = 0; i < length; i++) {
            Details det = new Details(imageid[i], imagename[i]);
            additems.add(det);

        }

        CAdapter c = new CAdapter(this, additems);
        hlist.setAdapter(c);

    }
}

我在tablelayout中有imageview和Textview，xml如下所示，我将其命名为photo.xml

<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginLeft="10dp"
    android:layout_marginRight="10dp"
    android:background="@android:color/black"
    android:gravity="center_vertical" >

    <TableRow
        android:id="@+id/row1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >

        <LinearLayout
            android:id="@+id/layout1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical" >

            <ImageView
                android:id="@+id/image1"
                android:layout_width="150dp"
                android:layout_height="150dp"
                android:background="@drawable/mymilan_circle_white" />

            <TextView
                android:id="@+id/tv1"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        </LinearLayout>

        <LinearLayout
            android:id="@+id/layout2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_alignParentTop="true"
            android:orientation="vertical" >

            <ImageView
                android:id="@+id/image2"
                android:layout_width="150dp"
                android:layout_height="150dp"
                android:background="@drawable/mymilan_circle_white" />

            <TextView
                android:id="@+id/tv2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        </LinearLayout>
    </TableRow>

    <TableRow
        android:id="@+id/row2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >

        <LinearLayout
            android:id="@+id/layout3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical" >

            <ImageView
                android:id="@+id/image3"
                android:layout_width="150dp"
                android:layout_height="150dp"
                android:background="@drawable/mymilan_circle_white" />

            <TextView
                android:id="@+id/tv3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        </LinearLayout>

        <LinearLayout
            android:id="@+id/layout4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_below="@id/layout2"
            android:orientation="vertical" >

            <ImageView
                android:id="@+id/image4"
                android:layout_width="150dp"
                android:layout_height="150dp"
                android:background="@drawable/mymilan_circle_white" />

            <TextView
                android:id="@+id/tv4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        </LinearLayout>
    </TableRow>

</TableLayout>

现在我的自定义Adapter类如下。

public class CAdapter extends ArrayAdapter<Details> {
    private LayoutInflater mInflater;
    private List<Details> item;
    private Context con;
    private int newpostion;

    public CAdapter(Context context, List<Details> objects) {
        super(context, R.layout.photo, objects);
        this.con = context;
        this.item = objects;
        mInflater = (LayoutInflater) getContext().getSystemService(
                Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public int getCount() {
        return item.size()/4;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Holder holder;
        newpostion = 0 * position;
        newpostion = 0 * position+1;
        newpostion = 0 * position+2;
        newpostion = 0 * position+3;

        if (convertView == null) {
            // Inflate the view since it does not exist
            convertView = mInflater.inflate(R.layout.photo, parent, false);

            // Create and save off the holder in the tag so we get quick access to inner fields
            // This must be done for performance reasons
            holder = new Holder();
            Log.i("VIEW HOLDER", "Position is" + newpostion);
            holder.trow = (TableRow) convertView.findViewById(R.id.row1);
            holder.trow2 = (TableRow) convertView.findViewById(R.id.row2);

            holder.image = (ImageView) convertView
                    .findViewById(R.id.image1);
            holder.textview = (TextView) convertView.findViewById(R.id.tv1);
            holder.thirdimage = (ImageView)convertView.findViewById(R.id.image3);
            holder.ttextview = (TextView) convertView.findViewById(R.id.tv3);
            holder.secondimage = (ImageView) convertView
                    .findViewById(R.id.image2);
            holder.stextview = (TextView) convertView.findViewById(R.id.tv2);
            holder.fourthimage = (ImageView) convertView.findViewById(R.id.image4);
            holder.ftextview = (TextView) convertView.findViewById(R.id.tv4);
            convertView.setTag(holder);
        } else {
            holder = (Holder) convertView.getTag();
        }
        Details det = (Details) getItem(newpostion);
        for (int i = 0; i < item.size(); i++) {
            if(i ==0){
                holder.textview.setText(det.getImgname());
                holder.image.setBackgroundResource(det.getImgid());
            }else if(i ==1){
                holder.stextview.setText(det.getImgname());
                holder.secondimage.setBackgroundResource(det.getImgid());
            }else if(i ==2){
                holder.thirdimage.setBackgroundResource(det.getImgid());
                holder.ttextview.setText(det.getImgname());
            }else if(i==3){
                holder.fourthimage.setBackgroundResource(det.getImgid());
                holder.ftextview.setText(det.getImgname());
            }
        }
    return convertView;
    }

    /** View holder for the views we need access to */
    private static class Holder {
        public TextView textview;
        public TextView stextview;
        public TextView ttextview;
        public TextView ftextview;

        public TableRow trow;
        public TableRow trow2;
        public ImageView image;
        public ImageView secondimage;
        public ImageView thirdimage;
        public ImageView fourthimage;

    }

}

但我的输出是这样的..

我想在那边有四张不同的图片。 1.狮子，2.Love，3.Android和4.握手。但是我在四个位置只得到握手。我是android的新手。请在这方面帮助我，非常感谢。

Answer 1

我会立即尝试解决我注意到的问题：

1）处理变量newpostion

此变量在getView方法中应该是本地的，不能在其他任何地方使用

getView开头的赋值没有意义

newpostion = 0 * position;
newpostion = 0 * position+1;
newpostion = 0 * position+2;
newpostion = 0 * position+3;

你不断覆盖价值观，只有最后一行有任何影响。

2）当您尝试为视图设置值时，您只能在循环外获取数据对象：

Details det = (Details) getItem(newpostion);

然后为所有四组视图分配相同的值。相反，你应该在for循环中找到正确的Details对象并使用它（你应该检查你的项目数不能被4整除的情况）

3）在同一个循环中，您循环遍历所有项目，而实际上您只想使用最多4个对象

4）当项目数不能被4整除时，getCount（）方法将返回不正确的结果 - 6/4将返回1

Answer 2

public class CAdapter extends ArrayAdapter<Details> {
    private LayoutInflater mInflater;
    private List<Details> item;
    private Context con;

    public CAdapter(Context context, List<Details> objects) {
        super(context, R.layout.photo, objects);
        this.con = context;
        this.item = objects;
        mInflater = (LayoutInflater) getContext().getSystemService(
                Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public int getCount() {
        if(item.size()%4 == 0){
            return item.size()/4; 
        }else
        return  (item.size()/4)+1;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Holder holder;
        /*newpostion = 0 * position;
        newpostion = 0 * position+1;
        newpostion = 0 * position+2;
        newpostion = 0 * position+3;*/

        if (convertView == null) {
            // Inflate the view since it does not exist
            convertView = mInflater.inflate(R.layout.photo, parent, false);

            // Create and save off the holder in the tag so we get quick access to inner fields
            // This must be done for performance reasons
            holder = new Holder();
            Log.i("VIEW HOLDER", "Position is" + position);
            holder.lay1 = (LinearLayout) convertView.findViewById(R.id.layout1);
            holder.lay2 = (LinearLayout) convertView.findViewById(R.id.layout2);
            holder.lay3 = (LinearLayout) convertView.findViewById(R.id.layout3);
            holder.lay4 = (LinearLayout) convertView.findViewById(R.id.layout4);

            holder.image = (ImageView) convertView
                    .findViewById(R.id.image1);
            holder.textview = (TextView) convertView.findViewById(R.id.tv1);
            holder.thirdimage = (ImageView)convertView.findViewById(R.id.image3);
            holder.ttextview = (TextView) convertView.findViewById(R.id.tv3);
            holder.secondimage = (ImageView) convertView
                    .findViewById(R.id.image2);
            holder.stextview = (TextView) convertView.findViewById(R.id.tv2);
            holder.fourthimage = (ImageView) convertView.findViewById(R.id.image4);
            holder.ftextview = (TextView) convertView.findViewById(R.id.tv4);
            convertView.setTag(holder);
        } else {
            holder = (Holder) convertView.getTag();
        }
        int i = 0 * position;
        if(i<=item.size()){
            Details det = (Details) getItem(i);
            holder.lay1.setVisibility(View.VISIBLE);
            holder.textview.setText(det.getImgname());
            holder.image.setBackgroundResource(det.getImgid());
        }
        int j = 0*position+1;
        if(j<=item.size()){
            Details det = (Details)getItem(j);
            holder.lay2.setVisibility(View.VISIBLE);
            holder.stextview.setText(det.getImgname());
            holder.secondimage.setBackgroundResource(det.getImgid());
        }
        int k = 0* position+2;
        if(k<item.size()){
            Details det = (Details)getItem(k);
            holder.lay3.setVisibility(View.VISIBLE);
            holder.thirdimage.setBackgroundResource(det.getImgid());
            holder.ttextview.setText(det.getImgname());
        }
        int l = 0* position+3;
        if(l<item.size()){
            Details det = (Details)getItem(l);
            holder.lay4.setVisibility(View.VISIBLE);
            holder.fourthimage.setBackgroundResource(det.getImgid());
            holder.ftextview.setText(det.getImgname());
        }
return convertView;
    }

    /** View holder for the views we need access to */
    private static class Holder {
        public TextView textview;
        public TextView stextview;
        public TextView ttextview;
        public TextView ftextview;

        public ImageView image;
        public ImageView secondimage;
        public ImageView thirdimage;
        public ImageView fourthimage;

        public LinearLayout lay1;
        public LinearLayout lay2;
        public LinearLayout lay3;
        public LinearLayout lay4;

    }

}

我的输出如下

因此我得到了输出..