ListView局部更新

原来看到虎牙直播上面最上面一个栏目上面有个刷新按钮，点击后只更新上面一个栏目数据更新，下面都没有更新，个人感觉还是蛮不错的，想到在listview里面怎么实现一部分数据的更新呢，后来研究了下，还真做到了，感觉还是蛮好玩的。记录一下。

public classMainActivityextendsAppCompatActivity{

ListViewlistview;

ArrayListitemList;

@Override

protected voidonCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

Toolbartoolbar=(Toolbar)findViewById(R.id.toolbar);

setSupportActionBar(toolbar);

FloatingActionButtonfab=(FloatingActionButton)findViewById(R.id.fab);

fab.setOnClickListener(newView.OnClickListener() {

@Override

public voidonClick(View view) {

Viewview1=listview.getChildAt(0);

MyAdapter.ViewHolderholder=(MyAdapter.ViewHolder)view1.getTag();

holder.textView.setText(" i am new ao");

}

});

itemList= newArrayList<>();

for(inti=0;i<10;i++) {

itemList.add(" old "+i);

}

listview=(ListView)findViewById(R.id.listview);

//ArrayAdapter adapter=new ArrayAdapter(MainActivity.this,R.layout.item,R.id.tv_item,itemList);

MyAdapteradapter= newMyAdapter(itemList,getApplicationContext());

listview.setAdapter(adapter);

}

}

public classMyAdapterextendsBaseAdapter{

ArrayListitemList;

LayoutInflaterinflater;

publicMyAdapter(ArrayListitemList,Context context){

this.itemList=itemList;

inflater=LayoutInflater.from(context);

}

@Override

public intgetCount() {

returnitemList.size();

}

@Override

publicObjectgetItem(intposition) {

returnitemList.get(position);

}

@Override

public longgetItemId(intposition) {

return0;

}

@Override

publicViewgetView(intposition,View convertView,ViewGroup parent) {

ViewHolderviewHolder;

if(convertView==null){

convertView=inflater.inflate(R.layout.item,null);

viewHolder=newViewHolder();

viewHolder.textView=(TextView)convertView.findViewById(R.id.tv_item);

convertView.setTag(viewHolder);

}else{

viewHolder=(ViewHolder)convertView.getTag();

}

viewHolder.textView.setText((String)getItem(position));

returnconvertView;

}

static classViewHolder{

TextViewtextView;

}

}

布局文件太简单了，就不贴了，学习记录，备忘。