Android ListView with different layouts for each row

Question

I am trying to determine the best way to have a single ListView that contains different layouts for each row  I know how to create a custom row   custom array adapter to support a custom row for the entire list view  but how can I implement many different row styles in the ListView

User · Answer

Take a look in the code below   First  we create custom layouts  In this case  four types   even xml   lt LinearLayout xmlns android  http   schemas android com apk res android      android layout width  match parent      android background   ff500000      android layout height  match parent  gt        lt TextView         android id    id text          android textColor   android color white          android layout width  match parent          android layout gravity  center          android textSize  24sp          android layout height  wrap content    gt     lt  LinearLayout gt    odd xml   lt LinearLayout xmlns android  http   schemas android com apk res android      android layout width  match parent      android background   ff001f50      android gravity  right      android layout height  match parent  gt        lt TextView         android id    id text          android textColor   android color white          android layout width  wrap content          android layout gravity  center          android textSize  28sp          android layout height  wrap content     gt     lt  LinearLayout gt    white xml   lt LinearLayout xmlns android  http   schemas android com apk res android      android layout width  match parent      android background   ffffffff      android gravity  right      android layout height  match parent  gt        lt TextView         android id    id text          android textColor   android color black          android layout width  wrap content          android layout gravity  center          android textSize  28sp          android layout height  wrap content      gt     lt  LinearLayout gt    black xml   lt LinearLayout xmlns android  http   schemas android com apk res android      android layout width  match parent      android background   ff000000      android layout height  match parent  gt        lt TextView         android id    id text          android textColor   android color white          android layout width  wrap content          android layout gravity  center          android textSize  33sp          android layout height  wrap content      gt     lt  LinearLayout gt    Then  we create the listview item  In our case  with a string and a type    public class ListViewItem           private String text          private int type           public ListViewItem String text  int type                this text   text              this type   type                     public String getText                 return text                     public void setText String text                this text   text                     public int getType                 return type                     public void setType int type                this type   type                     After that  we create a view holder  It s strongly recommended because Android OS keeps the layout reference to reuse your item when it disappears and appears back on the screen  If you don t use this approach  every single time that your item appears on the screen Android OS will create a new one and causing your app to leak memory    public class ViewHolder           TextView text           public ViewHolder TextView text                this text   text                     public TextView getText                 return text                     public void setText TextView text                this text   text                     Finally  we create our custom adapter overriding getViewTypeCount   and getItemViewType int position     public class CustomAdapter extends ArrayAdapter            public static final int TYPE ODD   0          public static final int TYPE EVEN   1          public static final int TYPE WHITE   2          public static final int TYPE BLACK   3           private ListViewItem   objects            Override         public int getViewTypeCount                 return 4                      Override         public int getItemViewType int position                return objects position  getType                       public CustomAdapter Context context  int resource  ListViewItem   objects                super context  resource  objects               this objects   objects                      Override         public View getView int position  View convertView  ViewGroup parent                 ViewHolder viewHolder   null              ListViewItem listViewItem   objects position               int listViewItemType   getItemViewType position                 if  convertView    null                     if  listViewItemType    TYPE EVEN                        convertView   LayoutInflater from getContext    inflate R layout type even  null                     else if  listViewItemType    TYPE ODD                        convertView   LayoutInflater from getContext    inflate R layout type odd  null                     else if  listViewItemType    TYPE WHITE                        convertView   LayoutInflater from getContext    inflate R layout type white  null                     else                       convertView   LayoutInflater from getContext    inflate R layout type black  null                                      TextView textView    TextView  convertView findViewById R id text                   viewHolder   new ViewHolder textView                    convertView setTag viewHolder                  else                   viewHolder    ViewHolder  convertView getTag                               viewHolder getText   setText listViewItem getText                  return convertView                     And our activity is something like this   private ListView listView        Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState            setContentView R layout activity main      here  you can create a single layout with a listview          listView    ListView  findViewById R id listview            final ListViewItem   items   new ListViewItem 40            for  int i   0  i  lt  items length  i                  if  i    4                    items i    new ListViewItem  White     i  CustomAdapter TYPE WHITE                 else if  i    9                    items i    new ListViewItem  Black     i  CustomAdapter TYPE BLACK                 else if  i   2    0                    items i    new ListViewItem  EVEN     i  CustomAdapter TYPE EVEN                 else                   items i    new ListViewItem  ODD     i  CustomAdapter TYPE ODD                                    CustomAdapter customAdapter   new CustomAdapter this  R id text  items           listView setAdapter customAdapter           listView setOnItemClickListener new AdapterView OnItemClickListener                  Override             public void onItemClick AdapterView adapterView  View view  int i  long l                    Toast makeText getBaseContext    items i  getText    Toast LENGTH SHORT  show                                         now create a listview inside mainactivity xml like this   lt  xml version  1 0  encoding  utf-8   gt   lt android support design widget CoordinatorLayout xmlns android  http   schemas android com apk res android      xmlns app  http   schemas android com apk res-auto      xmlns tools  http   schemas android com tools      android layout width  match parent      android layout height  match parent      android fitsSystemWindows  true      tools context  com example shivnandan gygy MainActivity  gt        lt android support design widget AppBarLayout         android layout width  match parent          android layout height  wrap content          android theme   style AppTheme AppBarOverlay  gt            lt android support v7 widget Toolbar             android id    id toolbar              android layout width  match parent              android layout height   attr actionBarSize              android background   attr colorPrimary              app popupTheme   style AppTheme PopupOverlay    gt        lt  android support design widget AppBarLayout gt        lt include layout   layout content main    gt        lt ListView         android layout width  match parent           android layout height  match parent           android id    id listView          android layout alignParentRight  true          android layout alignParentEnd  true            android layout marginTop  100dp    gt    lt  android support design widget CoordinatorLayout gt

User · Answer

In your custom array adapter  you override the getView   method  as you presumably familiar with  Then all you have to do is use a switch statement or an if statement to return a certain custom View depending on the position argument passed to the getView method  Android is clever in that it will only give you a convertView of the appropriate type for your position row  you do not need to check it is of the correct type  You can help Android with this by overriding the getItemViewType   and getViewTypeCount   methods appropriately

User · Answer

If we need to show different type of view in list-view then its good to use  getViewTypeCount   and getItemViewType   in adapter instead of  toggling a view VIEW GONE and VIEW VISIBLE can be very expensive task inside getView   which will affect the list scroll   Please check this one for use of getViewTypeCount   and getItemViewType   in Adapter   Link   the-use-of-getviewtypecount

User · Answer

I know how to create a custom row   custom array adapter to support a custom row for the entire list view  But how can one listview support many different row styles    You already know the basics  You just need to get your custom adapter to return a different layout view based on the row cursor information being provided   A ListView can support multiple row styles because it derives from AdapterView      An AdapterView is a view whose children are determined by an Adapter    If you look at the Adapter  you ll see methods that account for using row-specific views   abstract int getViewTypeCount      Returns the number of types of Views that will be created      abstract int getItemViewType int position     Get the type of View that will be created      abstract View getView int position  View convertView  ViewGroup parent     Get a View that displays the data       The latter two methods provide the position so you can use that to determine the type of view you should use for that row     Of course  you generally don t use AdapterView and Adapter directly  but rather use or derive from one of their subclasses  The subclasses of Adapter may add additional functionality that change how to get custom layouts for different rows   Since the view used for a given row is driven by the adapter  the trick is to get the adapter to return the desired view for a given row  How to do this differs depending on the specific adapter   For example  to use ArrayAdapter    override getView   to inflate  populate  and return the desired view for the given position  The getView   method includes an opportunity reuse views via the convertView parameter    But to use derivatives of CursorAdapter    override newView   to inflate  populate  and return the desired view for the current cursor state  i e  the current  row    you also need to override bindView so that widget can reuse views    However  to use SimpleCursorAdapter    define a SimpleCursorAdapter ViewBinder with a setViewValue   method to inflate  populate  and return the desired view for a given row  current cursor state  and data  column    The method can define just the  special  views and defer to SimpleCursorAdapter s standard behavior for the  normal  bindings    Look up the specific examples tutorials for the kind of adapter you end up using

User · Answer

ListView was intended for simple use cases like the same static view for all row items  Since you have to create ViewHolders and make significant use of getItemViewType    and dynamically show different row item layout xml s  you should try doing that using the RecyclerView  which is available in Android API 22   It offers better support and structure for multiple view types     Check out this tutorial on how to use the RecyclerView to do what you are looking for

User · Answer

Since you know how many types of layout you would have - it s possible to use those methods   getViewTypeCount   - this methods returns information how many types of rows do you have in your list  getItemViewType int position  - returns information which layout type you should use based on position  Then you inflate layout only if it s null and determine type using getItemViewType   Look at this tutorial for further information   To achieve some optimizations in structure that you ve described in comment I would suggest    Storing views in object called ViewHolder  It would increase speed because you won t have to call findViewById   every time in getView method  See List14 in API demos  Create one generic layout that will conform all combinations of properties and hide some elements if current position doesn t have it    I hope that will help you  If you could provide some XML stub with your data structure and information how exactly you want to map it into row  I would be able to give you more precise advise  By pixel

[android] Android ListView with different layouts for each row

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