ScrollView&ListView

<ScrollView
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="org.mobiletrain.a8_5scrollviewlistview.MainActivity">

<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent">

<ListView
android:id="@+id/lv"
android:layout_width="match_parent"
android:layout_height="match_parent"></ListView>
</LinearLayout>
</ScrollView>

public class MyAdapter extends BaseAdapter {
private List<String> list;
private Context context;
private LayoutInflater inflater;

public MyAdapter(Context context, List<String> list) {
this.context = context;
this.list = list;
inflater = LayoutInflater.from(context);
}

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

@Override
public Object getItem(int position) {
return list.get(position);
}

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

@Override
public View getView(int position, View convertView, ViewGroup parent) {
Log.d("google_lenve_fb", "getView: position:" + position);
ViewHolder holder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.listview_item, null);
holder = new ViewHolder();
holder.username = (TextView) convertView.findViewById(R.id.username);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.username.setText(list.get(position));
return convertView;
}

class ViewHolder {
TextView username;
}
}

/**
* 使用重新测量ListView高度的方式解决ScrollView和ListView嵌套问题，一定要将ListView放入到一个LinearLayout中
*/
public class MainActivity extends AppCompatActivity {

private List<String> list;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView listView = (ListView) findViewById(R.id.lv);
initData();
MyAdapter adapter = new MyAdapter(this, list);
//获取listview中item的总数
int count = adapter.getCount();
int totalHeight = 0;
for (int i = 0; i < count; i++) {
//获取ListView中每一个itemView
View view = adapter.getView(i, null, listView);
//0表示不指定itemView的宽高，由它自己测量
view.measure(0, 0);
//获取每一个item的高度
int measuredHeight = view.getMeasuredHeight();
totalHeight += measuredHeight;
}
ViewGroup.LayoutParams layoutParams = listView.getLayoutParams();
//获取item之间分隔线的总高度
int dividerHeight = listView.getDividerHeight() * (count - 1);
//重新给ListView指定高度
layoutParams.height = totalHeight + dividerHeight;
listView.setLayoutParams(layoutParams);
//重新测量View的宽高并显示，invalidate方法也会重新测量View的宽高并显示，
// 但是invalidate方法同时会调用onDraw方法，而requestLayout只会重新测量宽高，不重绘
listView.requestLayout();
//        listView.invalidate();
listView.setAdapter(adapter);
}

private void initData() {
list = new ArrayList<>();
for (int i = 0; i < 30; i++) {
list.add("李四：" + i);
}
}
}