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I keep getting a runtime error when I try to launch an activity.
Line where the error happen:
private OnItemClickListener mDeviceClickListener = new OnItemClickListener() {
public void onItemClick(AdapterView<?> av, View v, int arg2, long arg3) {
textView1.setText("Csatlakozás...");
String info = ((TextView) v).getText().toString(); // <-- ERROR HERE
String address = info.substring(info.length() - 17);
Intent i = new Intent(DeviceListActivity.this, MainActivity.class);
i.putExtra(EXTRA_DEVICE_ADDRESS, address);
startActivity(i);
}
};
Logcat:
java.lang.ClassCastException: android.support.constraint.ConstraintLayout cannot be cast to android.widget.TextView at arduinosensors.example.com.smarthome3.DeviceListActivity$1.onItemClick(DeviceListActivity.java:106)
What is happening here? It was fine until I started to use a custom array adapter with custom row layout.
Edit:
custom_row.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="TextView"
android:textSize="18sp"
android:textStyle="bold" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="TextView"
android:textSize="18sp" />
</LinearLayout>
</android.support.constraint.ConstraintLayout>
My adapter:
public class UsersAdapter extends ArrayAdapter<Adapter> {
public UsersAdapter(Context context, ArrayList<Adapter> users) {
super(context, 0, users);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Adapter user = getItem(position);
if (convertView == null) {
LayoutInflater sontInflater = LayoutInflater.from(getContext());
convertView = sontInflater.inflate(R.layout.custom_row,parent,false);
}
TextView one = (TextView) convertView.findViewById(R.id.textView);
TextView two = (TextView) convertView.findViewById(R.id.textView2);
one.setText(user.name);
two.setText(user.hometown);
return convertView;
}
}
Answer
From the documentation:
View: The view within the AdapterView that was clicked (this will be a view provided by the adapter)
In your case the View is the root ConstraintLayout. And as the error says you can’t cast it to TextView. To get the info you can use:
String info = v.findViewById(R.id.textView).getText().toString()