BaseAdapter是Android开发中使用频率很高一个ListView的基础Adapter，再此之上Android官方提供另外一个ArrayAdapter，一看它的名字就知道是封装了List集合的一个简易Adapter。Adapter经常搭配ViewHolder来使用，可以高效的复用已经生成的View，虽然ArrayAdapter已经很便捷，可是开发中，我们总要编写与ViewHolder连接的代码，懒惰是开发者的天性，所以我们在这里就把它抽象出来，让ArrayAdapter更便捷。
干货Gist点这里
MagicArrayAdapter.java
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
/**
* @author solo
*/
public abstract class MagicArrayAdapter<T> extends ArrayAdapter<T> {
private final LayoutInflater mInflater;
private final int mResource;
public MagicArrayAdapter(Context context, int resource) {
super(context, resource);
mResource = resource;
mInflater = LayoutInflater.from(context);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
MagicViewHolder<T> h;
if (convertView == null) {
convertView = mInflater.inflate(mResource, parent, false);
h = getViewHolder(position, convertView, parent);
convertView.setTag(h);
} else {
h = (MagicViewHolder<T>) convertView.getTag();
}
h.populateView(position, convertView, parent, getItem(position));
return convertView;
}
abstract public MagicViewHolder<T> getViewHolder(int position, View convertView, ViewGroup parent);
}
MagicViewHolder.java
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
/**
* @author solo
*/
public abstract class MagicViewHolder<T> {
public MagicViewHolder(View view) {
}
/**
* 更新AdapterView的每个item
*/
abstract public void populateView(int position, View convertView, ViewGroup parent, T item);
}
使用例子：
// Adapter
class YourAdapter extends MagicArrayAdapter<YourEntity> {
public YourAdapter(Context context) {
super(context, R.layout.your_layout);
}
@Override
public MagicViewHolder< YourEntity > getViewHolder(int position, View convertView, ViewGroup parent) {
return new ViewHolder(convertView, this);
}
}
// ViewHolder
static class ViewHolder extends MagicViewHolder<YourEntity> {
public ViewHolder(View view) {
// hold your view
}
@Override
public void populateView(int position, View convertView, ViewGroup parent, YourEntity item) {
// do something
}
}
代码很简单，相信你们一定一眼就明白。
感谢各位读者，喜欢的话点个赞吧，有哪里不懂的也可以在下方留言。:)
