在android中更改所选列表视图项图像问题

时间:2013-10-19 05:18:14

标签: android listview

在我的应用程序中,我只使用列表视图来显示图像和文本。这是我的适配器编码

ArrayAdapter<String> adapter=new ArrayAdapter<String>(MainActivity.this, R.layout.list_item, R.id.name, arrList);

    listProductCategories.setAdapter(adapter);

    listProductCategories.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                int position, long id) {

              ImageView imgview = (ImageView) view.findViewById(R.id.iv_listitem);
                 //And change its background here
                 imgview.setBackgroundResource(R.drawable.fail);

            String name = ((TextView) view.findViewById(R.id.name))
                    .getText().toString();
            Toast.makeText(MainActivity.this, "" + name, 10).show();

        }
    });

这是上面编码的屏幕截图。

enter image description here

这里我突出显示所选列表项。但是我的输出显示了一些列表视图项目图像背景改变了..

请给我一个解决方案....

<ImageView android:id="@+id/iv_listitem" 
android:layout_width="20dp" 
android:layout_height="20dp" 
android:layout_gravity="center_vertical" 
android:background="@drawable/next_unselect"
android:focusable="false" /> 
<TextView
android:id="@+id/name" 
android:layout_width="match_parent"   
android:layout_height="wrap_content" 
android:layout_gravity="center_vertical"
android:focusable="false" 
android:text="TextView"
android:textColor="#003366" /> 

列表项 -

  <ImageView android:id="@+id/iv_listitem" android:layout_width="20dp" android:layout_height="20dp" android:layout_gravity="center_vertical" android:background="@drawable/next_unselect" android:focusable="false" />

  <TextView android:id="@+id/name" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:focusable="false" android:text="TextView" android:textColor="#003366" />

2 个答案:

答案 0 :(得分:6)

我使用了Custom ListView和自定义适配器以及带有getter和setter的ItemsHolder类。

更改

  1. 获取项目的位置。
  2. 更改该位置的项目。
  3. 调用适配器上的notifyDataSetChanged()以刷新列表视图。
  4. 示例:

    ItemsHolder ih = hold.get(position);
    ih.setImage(decodeImage(R.drawable.appicon));
    ih.setName("Changed");
    cus.notifyDataSetChanged();
    

    test.xml

    <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"
    
    tools:context=".MenuActivity" >
    
    <ListView
        android:id="@+id/listView_Menu"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        >
    
    </ListView>
    </RelativeLayout>
    

    list_item.xml

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >
    
    <ImageView
        android:id="@+id/imageView_List_Item"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:contentDescription="@string/app_name"
        android:src="@drawable/ic_launcher" />
    
    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/imageView_List_Item"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="28dp"
        android:text="TextView" />
    
    </RelativeLayout>
    

    MainActivity.java

    public class MainActivity extends Activity {
    ArrayList<ItemsHolder> hold= new ArrayList<ItemsHolder>();
    CustomAdapter cus;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.test);
        Bitmap[] images = {decodeImage(R.drawable.ic_launcher),decodeImage(R.drawable.ic_launcher)};
        ListView list = (ListView)findViewById(R.id.listView_Menu);
        hold.add(new ItemsHolder(images[0],"image1"));
        hold.add(new ItemsHolder(images[1],"image2"));
         cus = new CustomAdapter(hold);
         list.setAdapter(cus);
         list.setOnItemClickListener(new OnItemClickListener()
         {
             public void onItemClick(AdapterView<?> parent, View
                     view, int position, long id)
             {
                    ItemsHolder ih = hold.get(position);
                    ih.setImage(decodeImage(R.drawable.appicon));
                    ih.setName("Changed");
                    cus.notifyDataSetChanged();
    
             }
         });
    
    }
    private Bitmap decodeImage(int res) {
        Bitmap bitmap = BitmapFactory.decodeResource(getResources(),res);               
        return bitmap;      
    }
    class ItemsHolder
    {
        Bitmap image;
        String name;
        public ItemsHolder(Bitmap bitmap, String string) {
            // TODO Auto-generated constructor stub
            image = bitmap;
            name =string;
        }
        public Bitmap getImage() {
            return image;
        }
        public void setImage(Bitmap image) {
            this.image = image;
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
    
    }
    class CustomAdapter extends BaseAdapter
    {
    
        LayoutInflater inflater;
        ArrayList<ItemsHolder> list;
        public CustomAdapter(ArrayList<ItemsHolder> list)
        {
            this.list=list;
            inflater= LayoutInflater.from(MainActivity.this);
    
        }
        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return list.size();
        }
        @Override
        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return arg0;
        }
        @Override
        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return 0;
        }
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            // TODO Auto-generated method stub
            ViewHolder holder;
            if(convertView==null)
            {
                holder = new ViewHolder();
                convertView = inflater.inflate(R.layout.list_item, null);
                holder.iv= (ImageView) convertView.findViewById(R.id.imageView_List_Item);
                holder.tv = (TextView) convertView.findViewById(R.id.textView1);
                convertView.setTag(holder);
            }
            else {
                holder = (ViewHolder)convertView.getTag();
            }
            ItemsHolder ih = list.get(position);
            holder.iv.setImageBitmap(ih.getImage());
            holder.tv.setText(ih.getName());
            return convertView;
        }
    
    }
    class ViewHolder
    {
        ImageView iv;
        TextView tv;
    }
    }
    

    enter image description here

    enter image description here

    编辑:

    在评论

    中提问

    listbkg.xml

    <?xml version="1.0" encoding="utf-8"?>
    <selector xmlns:android="http://schemas.android.com/apk/res/android">
        <item android:state_pressed="true" 
    
            android:drawable="@drawable/appicon" />
        <item  android:state_focused="false" 
            android:drawable="@drawable/ic_launcher" />
    </selector>
    

    然后是xml中的ImageView

    android:background="@drawable/listbkg" 
    

答案 1 :(得分:0)

我猜怎么能解决你的问题。但首先,我强烈建议您观看Android的ListView API首席架构师的精彩视频演示(如果您还没有):

http://www.youtube.com/watch?v=wDBM6wVEO70