如何从膨胀的布局中获取视图的参考

Question

I have a huge layout for my activity that i set using setContentView() . In that layout I have a TableLayout (named tableLayout in my Activity) that I want to populate. The rows of that TableLayout are customViews in a layout file(let's call that file tablerow_layout.xml ). Inside this layout i have some TextViews and ImageView. What I want to do is change the content of the TextView programatically, when I create the row. This is my code:

LayoutInflater layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View newRow = layoutInflater.inflate(R.layout.tablerow_layout, null, false);
TextView name = (TextView) newRow. findViewById(R.id.tablerow_name);
name.setText("THIS LINE");
tableLayout.addView(newRow);

Unfortunately my app crashes when I try to change the content of the TextView. I know that I could do this using a ListView, but I usually have a small number of rows and the overhead of creating another Adapter for the ListView is preatty big.

As @ρяσѕρєя K suggested I also tried newRow.findViewById(...) instead of findViewById(...) without any difference

Answer 1

How can I get a reference of a view from a inflated layout

Use View object which is returned from LayoutInflater.inflate method to access views from layout which is passed as first parameter to inflate method.

In your case, use newRow object for accessing views from R.layout.tablerow_layout layout:

TextView name = (TextView)newRow.findViewById(R.id.tablerow_name); 

Answer 2

  try

   {
   LayoutInflater layoutInflater = (LayoutInflater)   
   getSystemService(Context.LAYOUT_INFLATER_SERVICE);

     View newRow = layoutInflater.inflate(R.layout.tablerow_layout, null,   false);
     TextView name = (TextView) newRow.findViewById(R.id.tablerow_name);

     name.setText("THIS LINE");

    tableLayout.addView(newRow);

    }catch(Exception e)

    {

    e.printTracktrace();

    }

Answer 3

You are missing to set newRow in your Textview .

  View newRow = layoutInflater.inflate(R.layout.tablerow_layout, null, false);
  TextView name = (TextView)newRow.findViewById(R.id.tablerow_name);

Answer 4

Using IntelliJ Amiya's and ρяσѕρєя K's answers it worked for me with this code.

LayoutInflater inflater = LayoutInflater.from(this);
    LinearLayout linearLayout = 
(LinearLayout)findViewById(R.id.profileView);
    ViewGroup viewGroup = linearLayout;

    for (int i = 0; i < NUM_OF_PROFILES; i++){

        LinearLayout layout = (LinearLayout) inflater.inflate(R.layout.profile_badge_layout, viewGroup, false);
        linearLayout.addView(layout);

        TextView names = (TextView)layout.findViewById(R.id.profileName);
        ImageView images = (ImageView)layout.findViewById(R.id.profileImage);

        names.setText(""+i);


        viewGroup = layout;
    }

Each text had it's own i value. I believe you need to add the view first. Then you can change the values

Answer 5

How to use the success view in the onCreate function.? Even I am not able to use the View object because createSuccessView() returns a view.

class TrendingActivity : AppCompatActivity() {

private var currentState = UIState.loading
private lateinit var successView: View
private lateinit var loadingView: View
private lateinit var flContainer: ViewGroup

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_trending)
    flContainer = findViewById<FrameLayout>(R.id.fl_layout_container)
    loadingView = createLoadingView()
    flContainer.addView(loadingView)

    successView.layoutManager = LinearLayoutManager(this)
    val newTrendingArrayList = ArrayList<TrendingModel>()
    newTrendingArrayList.add(
        0,
        TrendingModel("octokit", "octokit.js")
    )

    val newTrendingAdapter = TrendingAdapter(newTrendingArrayList)

    successView.adapter = newTrendingAdapter

    val btnToggle = findViewById<Button>(R.id.btn_toggle)
    btnToggle.setOnClickListener {
        toggleView()
    }
}

private fun createSuccessView(): View {
    val view = layoutInflater.inflate(R.layout.trending_success, flContainer, false)
    successView = view.findViewById(R.id.rv_trending)
}