万能适配器

package bwie.universaladapter;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private ListView lv;
    int[] arr = {R.mipmap.img0, R.mipmap.img1, R.mipmap.img2, R.mipmap.img3,
            R.mipmap.img4, R.mipmap.img5, R.mipmap.img6,
            R.mipmap.img7, R.mipmap.img8, R.mipmap.img9};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lv = (ListView) findViewById(R.id.lv);
        List<Bean> list = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            list.add(new Bean(arr[i], "zhangsan" + i));
        }
        lv.setAdapter(new CommonAdapter<Bean>(this, list, R.layout.item) {
            @Override
            public void convert(ViewHolder helper, Bean bean) {
                TextView tv = helper.getView(R.id.textViews);
                tv.setText(bean.text);
                ImageView image = helper.getView(R.id.images);
                image.setImageResource(bean.getImage());
            }
        });
    }
}

 

package bwie.universaladapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;

import java.util.List;


public abstract class CommonAdapter<T> extends BaseAdapter {
    protected LayoutInflater mInflater;
    protected Context context;
    protected List<T> mDatas;
    protected final int mItemLayoutId;

    public CommonAdapter(Context context, List<T> mDatas, int mItemLayoutId) {
        this.mInflater = LayoutInflater.from(context);
        this.context = context;
        this.mDatas = mDatas;
        this.mItemLayoutId = mItemLayoutId;
    }

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

    @Override
    public T getItem(int position) {
        return mDatas.get(position);
    }

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final ViewHolder viewHolder = getViewHolder(position, convertView, parent);
        convert(viewHolder, getItem(position));
        return viewHolder.getConvertView();
    }

    public abstract void convert(ViewHolder helper, T item);

    private ViewHolder getViewHolder(int position, View convertView, ViewGroup parent) {
        return ViewHolder.get(context, convertView, parent, mItemLayoutId, position);

    }


}

 

package bwie.universaladapter;

import android.content.Context;
import android.util.SparseArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;


public class ViewHolder {

    private final SparseArray<View> mView;
    private View mConverView;
    private int mPosition;

    private ViewHolder(Context context, ViewGroup parent, int layoutId, int position) {
        this.mView = new SparseArray<>();
        mConverView = LayoutInflater.from(context).inflate(layoutId, parent, false);
        this.mPosition = position;
        //settag
        mConverView.setTag(this);
    }

    public View getConvertView() {
        return mConverView;
    }

    /**
     * 拿到一个ViewHolder对象
     *
     * @param context
     * @param convertView
     * @param layoutId
     * @param position
     * @return
     */
    public static ViewHolder get(Context context, View convertView, ViewGroup parent, int layoutId, int position) {
        if (convertView == null) {
            return new ViewHolder(context, parent, layoutId, position);
        }
        return (ViewHolder) convertView.getTag();
    }

    /**
     * 通过控件的Id获取对于的控件，如果没有则加入views
     *
     * @param viewId
     * @param <T>
     * @return
     */
    public <T extends View> T getView(int viewId) {
        View view = mView.get(viewId);
        if (view == null) {
            view = mConverView.findViewById(viewId);
            mView.put(viewId, view);
        }
        return (T) view;
    }

    /**
     * 为TextView设置字符串
     *
     * @param viewId
     * @param text
     * @return
     */
    public ViewHolder setText(int viewId, String text) {
        TextView tv = getView(viewId);
        tv.setText(text);
        return this;
    }

    public int getPosition() {
        return mPosition;
    }


}