I want to add views to an Android LinearLayout, but it is not working. What am I doing wrong?

Question

Like I said, I want to add views to an Android LinearLayout, but it is not working. What am I doing wrong. I want to have them inserted like this:

[ Click Me ]
added_view_01
added_view_02
added_view_03
etc.

Here is what I have for activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:orientation="vertical">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Click Me"
        android:onClick="addRow"/>

    <LinearLayout
        android:id="@+id/my_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:gravity="bottom"/>
</LinearLayout>

And here is what I have for MainActivity.java

public class MainActivity extends AppCompatActivity {

    private static int iterator = 0;

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

    public void addRow(View view){
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.US);
        StringBuffer stringBuffer = new StringBuffer();
        LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
        LinearLayout linearLayout = (LinearLayout)findViewById(R.id.my_layout);

        TextView textView = new TextView(this);
        textView.setLayoutParams(layoutParams);
        textView.setTextSize(34);
        stringBuffer.append("Timestamp: ");
        stringBuffer.append(sdf.format(new Date()));

        textView.setText(stringBuffer.toString());

        linearLayout.addView(textView, iterator);
        iterator++;
    }
}

Of course, if I change linearLayout.addView(textView, iterator); to linearLayout.addView(textView, 0);, it replaces the view at position 0, but it never appends the new view. How do I get it to keep appending a new view?

Thanks

Answer 1

You should at least be seeing one view. But it takes up the whole screen when you add it.

LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);

Try changing the height parameter to WRAP_CONTENT.