Question

I want to get the width of a LinearLayout element in my getView method of my custom adapter. My getView method looks like this:

@Override
    public View getView(int position, View v, ViewGroup parent) {
        View mView = v;

        if (mView == null) {

            LayoutInflater vi = (LayoutInflater) getContext().getSystemService(
                    Context.LAYOUT_INFLATER_SERVICE);
            mView = vi.inflate(R.layout.levelselector_item, null);


        } 
if (mView != null) {
...
LinearLayout ln = (LinearLayout) mView.findViewById(R.id.lineScore);
            LinearLayout lnTotal = (LinearLayout) mView.findViewById(R.id.lineScoreTotal);
int widthTotal = lnTotal.getWidth()/2;
                ln.getLayoutParams().height = 3;
                ln.getLayoutParams().width = widthTotal;
                ln.requestLayout();
                ln.setBackgroundColor(Color.parseColor("#eef05e"));

}
        return mView;
    }

The problem my widthTotal doesn’t seem to have a value. If I click on an item of the gridview and hit the back button, then I suddenly see a yellow bar. If I enter ln.getLayoutParams().width = 20; he also shows a yellow short bar. I just don’t know when or where I can get the width of the LinearLayout…

Answer 1

I got it to work properly. For those who might be interested:

I first set my border around my gridview to an amount which is controlable by adding to my gridview in xml:

android:listSelector="@null"
android:layout_margin="5dp"

Then I used a combination of Ted Hopp’s and Sameer’s solution: Since I know what the padding of my elements is; 5dp around the gridview, 2dp between the elements and 15dp in an element. I also have 3 items each row, this makes my code look like:

int parentW = parent.getWidth() - parent.getPaddingLeft() - parent.getPaddingRight();
                Resources r = C.getResources();
                float pxPaddingBetweenItem = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 2, r.getDisplayMetrics());
                float pxPaddingInItem = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 15, r.getDisplayMetrics());

                int totalBarWidth = (parentW - (int)(2*pxPaddingBetweenItem)  - (int)(6*pxPaddingInItem))/3;

And this takes me exactly where I want to be 🙂
Thanks!