Android ListView多布局*
使用listview多布局会出现一点问题:
由于多个item布局给单一的item布局是不一样的,使用起来,contentview的复用会出现问题。
避免出现问题的有这几个方法:
1.重写 getViewTypeCount() – 该方法返回多少个不同的布局
2.重写 getItemViewType(int) – 根据position返回相应的Item. type的值必须从0开始
3.根据view item的类型,在getView中创建正确的convertView
public class MyAdapter extends BaseAdapter { Context mContext; LinearLayout linearLayout = null; LayoutInflater inflater; TextView tex; final int VIEW_TYPE = 3; final int TYPE_1 = 0; final int TYPE_2 = 1; final int TYPE_3 = 2; public MyAdapter(Context context) { mContext = context; inflater = LayoutInflater.from(mContext); } @Override public int getCount() { return listString.size(); } //每个convert view都会调用此方法,获得当前所需要的view样式 @Override public int getItemViewType(int position) { //根据具体的ITME类型返回 return type; } // 返回三个不同的布局 @Override public int getViewTypeCount() { return 3; } @Override public Object getItem(int arg0) { return listString.get(arg0); } @Override public long getItemId(int position) { return position; } // 创建正确的contentview复用 @Override public View getView(int position, View convertView, ViewGroup parent) { // TODO Auto-generated method stub viewHolder1 holder1 = null; viewHolder2 holder2 = null; viewHolder3 holder3 = null; int type = getItemViewType(position); // 无convertView,需要new出各个控件 if (convertView == null) { Log.e("convertView = ", " NULL"); // 按当前所需的样式,确定new的布局 switch (type) { case TYPE_1: convertView = inflater.inflate(R.layout.listitem1, parent, false); holder1 = new viewHolder1(); holder1.textView = (TextView) convertView.findViewById(R.id.textview1); holder1.checkBox = (CheckBox) convertView.findViewById(R.id.checkbox); Log.e("convertView = ", "NULL TYPE_1"); convertView.setTag(holder1); break; case TYPE_2: convertView = inflater.inflate(R.layout.listitem2, parent, false); holder2 = new viewHolder2(); holder2.textView = (TextView) convertView.findViewById(R.id.textview2); Log.e("convertView = ", "NULL TYPE_2"); convertView.setTag(holder2); break; case TYPE_3: convertView = inflater.inflate(R.layout.listitem3, parent, false); holder3 = new viewHolder3(); holder3.textView = (TextView) convertView.findViewById(R.id.textview3); holder3.imageView = (ImageView) convertView.findViewById(R.id.imageview); Log.e("convertView = ", "NULL TYPE_3"); convertView.setTag(holder3); break; } } else { // 有convertView,按样式,取得不用的布局 switch (type) { case TYPE_1: holder1 = (viewHolder1) convertView.getTag(); Log.e("convertView !!!!!!= ", "NULL TYPE_1"); break; case TYPE_2: holder2 = (viewHolder2) convertView.getTag(); Log.e("convertView !!!!!!= ", "NULL TYPE_2"); break; case TYPE_3: holder3 = (viewHolder3) convertView.getTag(); Log.e("convertView !!!!!!= ", "NULL TYPE_3"); break; } } // 设置资源 switch (type) { case TYPE_1: holder1.textView.setText(Integer.toString(position)); holder1.checkBox.setChecked(true); break; case TYPE_2: holder2.textView.setText(Integer.toString(position)); break; case TYPE_3: holder3.textView.setText(Integer.toString(position)); holder3.imageView.setBackgroundResource(R.mipmap.ic_launcher); break; } return convertView; } } // 各个布局的控件资源 class viewHolder1 { CheckBox checkBox; TextView textView; } class viewHolder2 { TextView textView; } class viewHolder3 { ImageView imageView; TextView textView; }
下面是四个xml布局:
activity_main <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.example.listview_more.MainActivity"> <ListView android:id="@+id/listview" android:layout_width="match_parent" android:layout_height="match_parent" ></ListView> </RelativeLayout> listitem1 <?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="match_parent" android:orientation="vertical" > <TextView android:id="@+id/textview1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="hahaahha" /> <CheckBox android:id="@+id/checkbox" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </LinearLayout> listitem2 <?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="match_parent"> <TextView android:id="@+id/textview2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="1111111" /> </LinearLayout> listitme3 <?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="match_parent" android:orientation="vertical" > <TextView android:id="@+id/textview3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="888888888" /> <ImageView android:id="@+id/imageview" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </LinearLayout>