Android - get children inside a View

Question

Given a View how can I get the child views inside it   So I have a custom View and debugger shows that under mChildren there are 7 other views  I need a way to access these views but it doesn t seem like there is a public API to do this   any suggestions   EDIT   My custom view inherits from AdapterView

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Here is a suggestion  you can get the ID  specified e g  by android id    id   My Str    which was generated by R by using its given name  e g  My Str   A code snippet using getIdentifier   method would then be   public int getIdAssignedByR Context pContext  String pIdString           Get the Context s Resources and Package Name     Resources resources   pContext getResources        String packageName    pContext getPackageName            Determine the result and return it     int result   resources getIdentifier pIdString   id   packageName       return result      From within an  Activity  an example usage coupled with findViewById would be      Get the View  e g  a TextView  which has the Layout ID of  UserInput  int rID   getIdAssignedByR this   UserInput   TextView userTextView    TextView  findViewById rID

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As an update for those who come across this question after 2018  if you are using Kotlin  you can simply use the Android KTX extension property ViewGroup children to get a sequence of the View s immediate children

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I m just going to provide this answer as an alternative  IHeartAndroid s recursive algorithm for discovering all child Views in a view hierarchy  Note that at the time of this writing  the recursive solution is flawed in that it will contains duplicates in its result   For those who have trouble wrapping their head around recursion  here s a non-recursive alternative  You get bonus points for realizing this is also a breadth-first search alternative to the depth-first approach of the recursive solution   private List lt View gt  getAllChildrenBFS View v        List lt View gt  visited   new ArrayList lt View gt         List lt View gt  unvisited   new ArrayList lt View gt         unvisited add v        while   unvisited isEmpty              View child   unvisited remove 0           visited add child           if    child instanceof ViewGroup   continue          ViewGroup group    ViewGroup  child          final int childCount   group getChildCount            for  int i 0  i lt childCount  i    unvisited add group getChildAt i               return visited      A couple of quick tests  nothing formal  suggest this alternative is also faster  although that has most likely to do with the number of new ArrayList instances the other answer creates  Also  results may vary based on how vertical horizontal the view hierarchy is   Cross-posted from  Android   Get all children elements of a ViewGroup

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In order to refresh a table layout  TableLayout  I ended up having to use the recursive approach mentioned above to get all the children s children and so forth   My situation was somewhat simplified because I only needed to work with LinearLayout and those classes extended from it such as TableLayout   And I was only interested in finding TextView children  But I think it s still applicable to this question   The final class runs as a separate thread  which means it can do other things in the background before parsing for the children   The code is small and simple and can be found at github  https   github com jkincali Android-LinearLayout-Parser

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This method takes all views inside a layout  this is similar to Alexander Kulyakhtin s answer  The difference is  it accepts any type of parent layouts  amp  returns an Array List of views    public List lt View gt  getAllViews ViewGroup layout           List lt View gt  views   new ArrayList lt  gt             for int i  0  i lt  layout getChildCount    i                 views add layout getChildAt i                      return views

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You can always access child views via View findViewById   http   developer android com reference android view View html findViewById int    For example  within an activity   view       private void init       View child1   findViewById R id child1           or if you have a reference to a view       private void init View root      View child2   root findViewById R id child2

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for int index   0  index  lt    ViewGroup  viewGroup  getChildCount    index          View nextChild     ViewGroup  viewGroup  getChildAt index       Will that do

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If you not only want to get all direct children but all children s children and so on  you have to do it recursively   private ArrayList lt View gt  getAllChildren View v         if    v instanceof ViewGroup             ArrayList lt View gt  viewArrayList   new ArrayList lt View gt             viewArrayList add v           return viewArrayList             ArrayList lt View gt  result   new ArrayList lt View gt          ViewGroup vg    ViewGroup  v      for  int i   0  i  lt  vg getChildCount    i               View child   vg getChildAt i            ArrayList lt View gt  viewArrayList   new ArrayList lt View gt             viewArrayList add v           viewArrayList addAll getAllChildren child             result addAll viewArrayList             return result      To use the result you could do something like this          check if a child is set to a specific String     View myTopView      String toSearchFor    Search me       boolean found   false      ArrayList lt View gt  allViewsWithinMyTopView   getAllChildren myTopView       for  View child   allViewsWithinMyTopView            if  child instanceof TextView                TextView childTextView    TextView  child              if  TextUtils equals childTextView getText   toString    toSearchFor                     found   true                                    if   found            fail  Text      toSearchFor      not found within TopView

[android] Android - get children inside a View?

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