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Cannot center text when programmatically creating view from adaptor

I am using an adaptor to generate a view for each of several items. The view needs to show an image with centered text below it. I create a linear layout and add an image view and text view.
To show the problem I have changed the background colors to green for the linear layout and red for the text view...
Obviously the text is showing left aligned instead of centered. Here is the simple code in the adaptor GetView method...
public override View GetView(int position, View convertView, ViewGroup parent)
{
ImageView imageView = new ImageView(_context);
LinearLayout.LayoutParams imageViewParam = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MatchParent, LinearLayout.LayoutParams.WrapContent);
imageView.LayoutParameters = imageViewParam;
imageView.Id = 1000 + position;
imageView.SetImageResource(Resource.Drawable.Code);
TextView textView = new TextView(_context);
LinearLayout.LayoutParams textViewParam = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MatchParent, LinearLayout.LayoutParams.WrapContent);
textView.LayoutParameters = textViewParam;
textView.Text = OPTIONS_TEXT[position];
textView.SetBackgroundColor(Color.Red);
textView.SetForegroundGravity(GravityFlags.CenterHorizontal);
LinearLayout linear = new LinearLayout(_context);
linear.LayoutParameters = new GridView.LayoutParams(200, 172);
linear.SetBackgroundColor(Color.Green);
linear.Orientation = Orientation.Vertical;
linear.AddView(imageView);
linear.AddView(textView);
return linear;
}
As far as I can work out, you cannot set the layout_gravity setting when generating the view programmatically and so I tried setting the foreground gravity but has no effect at all.
I have tried everything I can think of but nothing gets that text centered!

Set gravity center to LinearLayout.LayoutParams of TextView i.e.
textViewParam.gravity = Gravity.CENTER;

Combining imageView and TextView in a List

Hi I am developing an app in android where I use a subclass that extends BaseExpandableListAdapter. Right now I have problem to combine ImageView and TextView in the list that is showing. Yesterday I found this link on stackoverflow that helped me to make this combination.
Overlay text over imageview in framelayout programmatically - Android
So it works FINE! - until I click on a listItem. The app chrash and the logcat tells me that
"android.widget.RelativeLayout" cannot be cast to android.widget.ImageView. This exception comes the getGroupView() in the class that extends BaseExpandableListAdapter . Why does this happen? (RelativeLayout extends View).
Am I completely on the wrong way when I try to return a RelativeLayout instead of an ImageView?
Here's my code from getGroupView (I'm a bit messy because I am in a teststate) :
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
ImageView row = (ImageView) convertView;
RelativeLayout rLayout = new RelativeLayout(mContext);
LayoutParams rlParams = new LayoutParams(LayoutParams.FILL_PARENT
,LayoutParams.FILL_PARENT);
rLayout.setLayoutParams(rlParams);
if(row == null) {
row = new ImageView(mContext);
}
row.setImageResource(R.drawable.ic_launcher);
row.setScaleType(ImageView.ScaleType.FIT_START);
RelativeLayout.LayoutParams tParams = new RelativeLayout.LayoutParams
(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);
tParams.addRule(RelativeLayout.CENTER_HORIZONTAL, RelativeLayout.TRUE);
tParams.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM, RelativeLayout.TRUE);
TextView text=new TextView(mContext);
text.setText("GOLDEN Gate");
text.setTextColor(Color.WHITE);
text.setTypeface(Typeface.DEFAULT_BOLD);
text.setLayoutParams(tParams);
rLayout.addView(row);
rLayout.addView(text);
return rLayout;
}

The statement ImageView row = (ImageView) convertView; gives the exception because u r trying to convert the RelativeLayout to ImageView.
You must return the convertView in getViewGroup() method but you are returning the RelativeLayout i.e., return rLayout;
Solution :
Add a ImageView and TextView inside a RelativeLayout. Set that layout for ListItem by inflating it inside getView() method and assign the inflated layout to convertView. Return the convertView in getView() method;

How to set height of Gallery view cell equals Gallery height?

I have Gallery control with ImageView as cell View. I need to have ImageView size equals the Gallery height. How can I do that? I tried to set height like this:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
FrameLayout retval = (FrameLayout) convertView;
ImageView imageView = (ImageView) retval.findViewById(R.id.image);
imageView.setLayoutParams(new FrameLayout.LayoutParams(parent.getHeight(), parent.getHeight()));
But first cell has height equals zero but next cells has right value.

Why not just set the imageView to fill the parent container through the params?
#Override
public View getView(int position, View convertView, ViewGroup parent) {
FrameLayout retval = (FrameLayout) convertView;
ImageView imageView = (ImageView) retval.findViewById(R.id.image);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT, LinearLayout.LayoutParams.FILL_PARENT);
imageView.setLayoutParams(layoutParams);
That is, unless you want the width of the imageview to be equal to the height of the gallery. Then this would not work

I think you should set layoutParams on cell itself and let image view to scaleXY to the cell.
retval.setLayoutParams(new FrameLayout.LayoutParams(parent.getHeight(), parent.getHeight());
imageView.setScaleType(ScaleType.FIT_XY);

Programmatically Position Views in RelativeLayout

I want my TextView to appear below my ImageView in a RelativeLayout that is going into a GridView. I've tried:
public override View GetView(int position, View convertView, ViewGroup parent)
{
RelativeLayout rl = new RelativeLayout(context);
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.FillParent, ViewGroup.LayoutParams.FillParent);
ImageView imageView;
TextView tv;
imageView = new ImageView(context);
imageView.LayoutParameters = new GridView.LayoutParams(250, 250);
imageView.SetScaleType(ImageView.ScaleType.CenterCrop);
imageView.SetPadding(8, 8, 8, 8);
imageView.SetImageResource(thumbIds[position]);
imageView.Id = position;
lp.AddRule(LayoutRules.Below, position);
lp.AddRule(LayoutRules.CenterHorizontal);
tv = new TextView(context);
tv.Text = stringIds[position].ToString();
tv.SetTextSize(Android.Util.ComplexUnitType.Dip, 20);
tv.SetTextColor(Android.Graphics.Color.WhiteSmoke);
tv.LayoutParameters = lp;
rl.AddView(imageView);
rl.AddView(tv);
return rl;
}
But the TextView always shows up on top of the ImageView.

Check out this question.
When you call rl.AddView(tv), you should include the LayoutParams rl.AddView(tv, lp).

You have to use
imageView.setLayoutParams(lp) in order to assign the params to your view.
How do you setLayoutParams() for an ImageView?

Since my content is not dynamic, I worked around the issue by simply editing my image in Paint and placing text below the image. Then I made that the background for the ImageView.

How to add TextView in Runtime?

How to add a new TextView to a layout in run time? is it possible?

Complete solution:
View parent; //parent view where to add
ViewGroup layout=new LinearLayout(context);
layout.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
TextView tv1=new TextView(context);
tv1.setText("Test1");
TextView tv2=new TextView(context);
tv2.setText("Test2");
layout.addView(tv1);
layout.addView(tv2);
parent.addView(layout);

Programmatically adding TextView (or View in general) to layout (or ViewGroup in general) is possible, check ViewGroup's public void addView (View child, int index) method.