Develop Reference

onItemClick() receives layout instead of TextView

I have a ListView in my Activity whose rows are populated by logins fetched from a database. Each row in my ListView contains one TextView inside a Constraint Layout. When user touches one of the rows of this ListView, another activity should be launched. I used OnItemClickListener to achieve this and everything seems to work fine, but onClickItem() method from Listener receives a reference to object of type ConstraintLayout and I need to obtain text from TextView inside this layout. How can I do this?
Here is my xml of a simple row:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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">
<TextView
android:id="#+id/row"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="32dp"
android:text="TextView"
android:textSize="24sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
And here is my implementation of OnItemClickListener:
private AdapterView.OnItemClickListener myItemClickListener = new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
TextView currentView = (TextView) view; // Here I get an exception that ConstraintLayout cannot be casted to TextView
String login = currentView.getText().toString();
Intent intent = new Intent(Powitanie.this,UserPanel.class);
intent.putExtra(LOGIN, login);
Powitanie.this.startActivity(intent);
}
};

We can use getChildAt() method. onItemClick() receives reference to a view. We can cast it to ConstraintLayout and get a child from a specified index.
private AdapterView.OnItemClickListener myItemClickListener = new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
ConstraintLayout layout = (ConstraintLayout) view;
TextView currentView = (TextView) layout.getChildAt(0); // In getChildAt we need to specify index of a child. In this case it's 0.
String login = currentView.getText().toString();
Intent intent = new Intent(Powitanie.this,UserPanel.class);
intent.putExtra(LOGIN, login);
Powitanie.this.startActivity(intent);
}
};

Android ListView with subitem causes TwoLineListItem cannot be cast to android.widget.TextView

I've created a ListView that can display a list of items and subitems, following this question: android-listview-subitems.
However, when I click on one of the rows, I get the error: E/MessageQueue-JNI: java.lang.ClassCastException: android.widget.TwoLineListItem cannot be cast to android.widget.TextView
The error only started occurring once I added a subitem to each item in the ListView.
The error occurs in the listener for the listView which is this code below:
//listview listener
lvAppFeatures.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//find the selected item and store the value to send to next screen
strSelectedFeature = ((TextView) view).getText().toString();
//move to display screen
Intent switchActivity = new Intent(MainActivity.this,
NextActivity.class);
startActivity(switchActivity);
}
});
Is there a way to have a set of items and a subitems in a ListView but have intent to open another activity work?

It seems you're using android.R.layout.simple_list_item_2
<TwoLineListItem xmlns:android="http://schemas.android.com/apk/res/android"
android:paddingTop="2dip"
android:paddingBottom="2dip"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<TextView android:id="#android:id/text1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
style="?android:attr/listItemFirstLineStyle"/>
<TextView android:id="#android:id/text2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="#android:id/text1"
style="?android:attr/listItemSecondLineStyle" />
</TwoLineListItem>
A)
get item directly from adapter
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//find the selected item and store the value to send to next screen
strSelectedFeature = (String)parent.getAdapter().getItem(position);
or B), if you want to have access to textviews
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//find the selected item and store the value to send to next screen
TextView textView1 = view.findViewById(android.R.id.text1);
TextView textView2 = view.findViewById(android.R.id.text2);
//do other things like textView1.getText() etc

Get the text of TextView of Item of ListView

I want to get the text of a TextView that is in a ListView's item.
See the code and you will find what's my question.
Activity.java:
SimpleAdapter adapter = new SimpleAdapter(
rootView.getContext(),
result,
R.layout.article_list_item,
new String[]{"article_title", "article_PubDate", "article_category", "article_articleNo"},
new int[]{R.id.article_title, R.id.article_PubDate, R.id.article_category, R.id.article_articleNo});
ListView articleItem.setAdapter(adapter);
articleItem.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//I want get the text of R.id.article_articleNo(see article_list_item.xml)?
//What should I do?
}
});
article_list_item.xml :
<?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"
android:id="#+id/article">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="文章标题"
android:id="#+id/article_title"
android:layout_gravity="center_horizontal" />
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="30-Apr-2014"
android:id="#+id/article_PubDate"
android:layout_gravity="center_horizontal"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="personal_finance"
android:id="#+id/article_category"
android:layout_gravity="center_horizontal"
android:layout_marginLeft="20dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="9312"
android:id="#+id/article_articleNo"
android:layout_gravity="center_horizontal"
android:layout_marginLeft="20dp"/>
</LinearLayout>
</LinearLayout>
That's all!!
I want to get the text of R.id.article_article (see article_list_item.xml).
How can I do it?

Does this work for you?
articleItem.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String text = result.get(position).get("article_articleNo");
//^^ does not necessarily need to be a string,
// make this whatever data type you are storing in the map
}
});
The idea is that in your SimpleAdapter, you are populating your ListView with a List<Map<String,Object>> (in this case named result).
Therefore, you can get that specific Map<String,Object> from the List by using .get(position), then once again using .get("article_articleNo") to get the Object from the map.
Edit after seeing your comment: Try this:
articleItem.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
TextView tv = (TextView) view.findViewById(R.id.article_articleNo);
String text = tv.getText().toString();
}
});

First of all, forget about the xml layout. It's just a placeholder for data, which is used to define the layout of the data, and has got nothing to do with storing the data.
Now, your problem statement can be re-stated as: how to fetch data from an array (or list or arraylist or whatever the format of your result is) on clicking list item.
Hmm. Sounds simple now.
Refer to #RougeBaneling's answer for technical details.

Unable to do Operation on child of listView

I want to get the child of listview and set the visibility of its two hidden element to true.
My code is
canvasListView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
/*
joinCanvasBtn.setEnabled(true);
joinCanvasPasswordTxt.setEnabled(true);*/
Log.d(TAG,"Selected positon : "+position);
int index = canvasListView.getFirstVisiblePosition() + position;
View v = canvasListView.getChildAt(index);
if(v!=null) {
joinCanvasBtn = (Button) v.findViewById(R.id.joinCanvasBtn);
canvasPassword = (EditText) v.findViewById(R.id.joinCanvasPasswordTxt);
joinCanvasBtn.setVisibility(View.VISIBLE);
joinCanvasPasswordTxt.setVisibility(View.VISIBLE);
}
else {
Log.d(TAG,"Unable to find the selected child of listView");
}
}
});
But this is not working its giving me Nullpointer exception. My layout file is given below. Basically I want to show the password and join button whenever user click on that row.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="?android:attr/listPreferredItemHeight"
android:padding="6dip">
<!-- Item Name -->
<TextView
android:id="#+id/canvasName"
android:height="100dp"
/>
<TextView
android:id="#+id/canvasCreator"
android:text="TextView" />
<EditText
android:id="#+id/joinCanvasPasswordTxt"
android:visibility="invisible"
/>
<Button
android:id="#+id/joinCanvasBtn"
android:text="Join"
android:visibility="invisible"
/>
</LinearLayout>
Please help me to find the solution

Try to write
int index = position - canvasListView.getFirstVisiblePosition();
instead of
int index = canvasListView.getFirstVisiblePosition() + position;

android view extraction from OnItemClickMethod

I have a list View and In the adaptor of this list View i have a method
public void onItemClick(AdapterView<?> AdapterView, View View,
int position, long id)
each row of list contain 3 view
xml for row is
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:background="#android:color/white" android:padding="5dp">
<TextView android:id="#+id/name" android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="20dp" android:textStyle="bold" android:textColor="#android:color/black"
android:layout_marginTop="10dp" android:focusable="false">
</TextView>
<TextView android:id="#+id/street"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:layout_below="#id/name"
android:textColor="#android:color/black" android:focusable="false">
</TextView>
<ImageView android:id="#+id/pic" android:src="#drawable/pic"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:layout_alignParentRight="true" android:layout_marginRight="10dp"
android:layout_below="#id/name" android:focusable="false">
</ImageView>
</RelativeLayout>
In OnItemClickMethod i want to find click event on these 3 view. how can i do this?
Note: if i am using view.getId() it is returning -1 for first row . so i am unable to use this one.
if(view.getId() == R.id.name){
dotask();
}
Update: I just call onClick method inside getView Method
setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Toast.makeText(context,position.toString(), Toast.LENGTH_LONG).show();
}
});
and my problem get solved.
Thanks FunkTheMonk and Vikky.

Here in onItemClick View view refers to RelativeLayout and not textviews according to your xml file.
public void onItemClick(AdapterView<?> AdapterView, View View, int position, long id) {
TextView name = View.findViewById ( R.id.name );
for other views .......
}

You can set an onClickListener on Views inside the row used in a ListView.
abstract class Clicker implements OnClickListener {
int mPosition;
public Clicker(int position) {
mPosition = position;
}
}
public View getView(int position, View convertView, ViewGroup parent) {
if(convertView == null) {
//inflate
}
//do your stuff
convertView.findViewById(R.id.button1).setOnClickListener(new Clicker(position) {
public void onClick(View v)
{
int row = mPosition;
//button 1 clicked
}
});
convertView.findViewById(R.id.button2).setOnClickListener(new Clicker(position) {
public void onClick(View v)
{
int row = mPosition;
//button 2 clicked
}
});
}
onItemClick gives only the selected row, and provides no touch co-ordinates so you can't manually determine which child has been clicked

You can use view.findViewById on the view you get in onItemClick. It says here ( http://www.vogella.de/articles/AndroidListView/article.html ) that it's a relatively lengthy operation, and that the recommended way is using the view's tag to store its relevant child-views. It seems logical, but it might be premature optimization in your case - depending on the number of uses for your view.