Add and Remove view dynamically keep track of child views

I have a old example of "Add and Remove view dynamically". Somebody ask how the Remove button keep track of the views. So I modify the example to explain in more details.

In this example, when user click on the Add button, it will create a child View, addView. The addView have a Button, buttonRemove. The buttonRemove have its own OnClickListener object. The OnClickListener object refer to the specified addView when it is created.

That means the OnClickListener object of the buttonRemove in the first child view("abc") not the same object in the second child view("abcdef"), not the same object in the third child view("abcdefghi")...All have its own individual OnClickListener object. And each OnClickListener object refer to a specified addView object. Such that it can keep track of the child Views, addView.


MainActivity.java

package com.blogspot.android_er.androiddynamicview;

import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.text.method.ScrollingMovementMethod;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

 EditText textIn;
 Button buttonAdd;
 LinearLayout container;
 TextView reList, info;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);

 textIn = (EditText)findViewById(R.id.textin);
 buttonAdd = (Button)findViewById(R.id.add);
 container = (LinearLayout)findViewById(R.id.container);
 reList = (TextView)findViewById(R.id.relist);
 info = (TextView)findViewById(R.id.info);
 info.setMovementMethod(new ScrollingMovementMethod());

 buttonAdd.setOnClickListener(new View.OnClickListener(){
 @Override
 public void onClick(View v) {
 LayoutInflater layoutInflater =
 (LayoutInflater) getBaseContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
 final View addView = layoutInflater.inflate(R.layout.row, null);
 TextView textOut = (TextView)addView.findViewById(R.id.textout);
 textOut.setText(textIn.getText().toString());
 Button buttonRemove = (Button)addView.findViewById(R.id.remove);

 final View.OnClickListener thisListener = new View.OnClickListener(){
 @Override
 public void onClick(View v) {
 info.append("thisListener called: " + this + " ");
 info.append("Remove addView: " + addView + " ");
 ((LinearLayout)addView.getParent()).removeView(addView);

 listAllAddView();
 }
 };

 buttonRemove.setOnClickListener(thisListener);
 container.addView(addView);

 info.append(
 "thisListener: " + thisListener + " "
 + "addView: " + addView + " "
 );

 listAllAddView();
 }
 });
 }

 private void listAllAddView(){
 reList.setText("");

 int childCount = container.getChildCount();
 for(int i=0; i<childCount; i++){
 View thisChild = container.getChildAt(i);
 reList.append(thisChild + " ");
 }
 }
}

layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
 
 android_layout_width="match_parent"
 android_layout_height="match_parent"
 android_orientation="horizontal"
 android_padding="16dp"
 tools_context="com.blogspot.android_er.androiddynamicview.MainActivity">


 <LinearLayout
 android_layout_width="0dp"
 android_layout_height="match_parent"
 android_layout_weight="1"
 android_orientation="vertical">

 <RelativeLayout
 android_layout_width="match_parent"
 android_layout_height="wrap_content">

 <Button
 android_id="@+id/add"
 android_layout_width="wrap_content"
 android_layout_height="wrap_content"
 android_layout_alignParentRight="true"
 android_text="Add" />

 <EditText
 android_id="@+id/textin"
 android_layout_width="match_parent"
 android_layout_height="wrap_content"
 android_layout_alignParentLeft="true"
 android_layout_toLeftOf="@id/add" />
 </RelativeLayout>

 <LinearLayout
 android_id="@+id/container"
 android_layout_width="match_parent"
 android_layout_height="wrap_content"
 android_orientation="vertical"></LinearLayout>

 </LinearLayout>

 <LinearLayout
 android_layout_width="0dp"
 android_layout_height="match_parent"
 android_layout_weight="1"
 android_orientation="vertical">

 <TextView
 android_layout_width="wrap_content"
 android_layout_height="wrap_content"
 android_layout_gravity="center_horizontal"
 android_autoLink="web"
 android_text="http://android-er.blogspot.com/"
 android_textStyle="bold" />

 <TextView
 android_id="@+id/relist"
 android_layout_width="match_parent"
 android_layout_height="0dp"
 android_layout_weight="1"
 android_textStyle="bold"
 android_background="#E0E0E0"/>
 <TextView
 android_id="@+id/info"
 android_layout_width="match_parent"
 android_layout_height="0dp"
 android_layout_weight="1"
 android_textStyle="italic"
 android_background="#D0D0D0"
 android_gravity="bottom"/>

 </LinearLayout>
</LinearLayout>

layout/row.xml, the layout of the child views.

<RelativeLayout 
 
 android_layout_width="match_parent"
 android_layout_height="wrap_content">
 <Button
 android_id="@+id/remove"
 android_layout_width="wrap_content"
 android_layout_height="wrap_content"
 android_layout_alignParentRight="true"
 android_text="Remove"/>
 <TextView
 android_id="@+id/textout"
 android_layout_width="match_parent"
 android_layout_height="wrap_content"
 android_layout_alignParentLeft="true"
 android_layout_toLeftOf="@id/remove"/>
</RelativeLayout>

Download the files (Android Studio Format) .

Its another approach to share a common OnClickListener between all buttonRemove.

more:
- Add and Remove view dynamically, with EditText/AutoCompleteTextView inside

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