创建自定义Adapter命名为TestAdapter
public class TestAdapter extends BaseAdapter {
private Context mContent;
private List<Fruit> mData;
public TestAdapter(Context context, List<Fruit> data) {
this.mContent = context;
this.mData = data;
}
@Override
public int getCount() {
return mData== null? 0 :mData.size();
}
@Override
public Object getItem(int position) {
return mData.get(position);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int possition, View view, ViewGroup viewGroup) {
ViewHolde viewHodle;
if (view == null) {
viewHodle = new ViewHolde();
view = LayoutInflater.from(mContent).inflate(R.layout.item,viewGroup,false);
viewHodle.imageView = view.findViewById(R.id.image);
viewHodle.name = view.findViewById(R.id.name);
viewHodle.size = view.findViewById(R.id.size);
viewHodle.button = view.findViewById(R.id.button);
view.setTag(viewHodle);
}else {
viewHodle = (ViewHolde) view.getTag();
}
final Fruit fruit = mData.get(possition);
viewHodle.name.setText(fruit.getName());
viewHodle.imageView.setImageResource(fruit.getImageId());
viewHodle.size.setText(fruit.getSize());
viewHodle.button.setText(fruit.getButtonText());
viewHodle.button.setTag(possition);
viewHodle.button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//TODO 点击事件
switch ((Integer) view.getTag()){
case 0:
Util.showToast(mContent,"1");
break;
case 1:
Util.showToast(mContent,"2");
break;
case 2:
Util.showToast(mContent,"3");
break;
}
}
});
return view;
}
class ViewHolde {
ImageView imageView;
TextView name;
TextView size;
Button button;
}
}
当view为空的时候,创建一个ViewHolder对象,并将控件的实例都存放在ViewHolder里,然后调用View的setTag()方法,将ViewHolder对象存储在View中。当convertView不为空的时候则调用View的getTag()方法,把ViewHolder重新取出。这样所有控件的实例都缓存在了ViewHolder里,就没有必要每次都通过findViewById()方法来获取控件实例了。
MainActivity文件
public class MainActivity extends AppCompatActivity {
private List<Fruit> DataList = new ArrayList<Fruit>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.my_listview);
initDataList(); // 初始化
TestAdapter adapter = new TestAdapter(MainActivity .this,DataList);
ListView listView = (ListView) findViewById(R.id.list_view_2);
listView.setAdapter(adapter);
}
private void initDataList() {
Fruit a = new Fruit("王者农药", R.drawable.log,"下载","10m");
DataList.add(a);
Fruit b = new Fruit("吃鸡战场",R.drawable.log2,"下载","20m");
DataList.add(b);
Fruit c = new Fruit("氪金", R.drawable.log3,"下载","30m");
DataList.add(c);
}
}
my_listview.xml文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id="@+id/list_view_2"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
item.xml文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:descendantFocusability="blocksDescendants">
<ImageView
android:id="@+id/image"
android:src="@drawable/log"
android:layout_width="70dp"
android:layout_height="70dp"
/>
<LinearLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginLeft="20dp"
android:layout_marginTop="5dp"
android:layout_weight="3">
<TextView
android:id="@+id/name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="5dp"
android:layout_marginTop="2dp"
android:text="乱斗堂"
android:textColor="#130000"
android:textSize="18dp"/>
<TextView
android:id="@+id/size"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:layout_marginLeft="5dp"
android:textColor="#93851f"
android:text="65M"
android:textSize="20dp"/>
</LinearLayout>
<Button
android:layout_weight="1"
android:id="@+id/button"
android:layout_marginTop="12dp"
android:layout_width="40dp"
android:layout_height="50dp"
android:text="下载"
android:textSize="20dp"/>
</LinearLayout>
Android_listview设置每条信息的间距
设置listView的item间距,可以在xml布局文件中的listView下设置xml属性:
android:divider="#00000000"
android:dividerHeight=“18dp”
解释:分隔线透明,高度为18dp。