Android get Fragment width

Question

I have a layout with 3 fragments:

<LinearLayout android:id="@+id/acciones"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">

<LinearLayout
android:id="@+id/fragment1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1">

</LinearLayout>


<LinearLayout
android:id="@+id/fragment2"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1">

</LinearLayout>

<LinearLayout
android:orientation="vertical"
android:id="@+id/f3"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1">

</LinearLayout>

</LinearLayout>

In the first fragment I have a TableLayout in which I have one custom TextView in each row. I want to know the width of the fragment because if the custom TextView is wider than the fragment, I'll set the number of lines necessary.

This is what I've done in my custom TextView:

@Override
protected void onMeasure (int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);

mMaxWidth = (float) (getMeasuredWidth());
}

With this line I got the width from the three Fragments, not only the one which contains the custom TextView.

Thanks.

Answer 1

You should be able to set the width of the TextView to be fill_parent, in which case it will do the wrapping for you. You should not set the widths of your layouts to be match_parent since it is inefficient when you're using layout weights.

Since android's layout system is occasionally mysterious with regards to view sizes, if setting the TextView width to be fill_parent actually makes it take up the whole screen (as your question appears to be implying) do the following:

Set your TextView width to 0 by default. In onCreate of your activity, after setting the content view:

findViewById(R.id.acciones).getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        final int fragmentWidth = findViewById(R.id.releventFragmentId).getWidth();
        if (fragmentWidth != 0){
            findViewById(R.id.yourTextViewId).getLayoutParams().width = fragmentWidth;
        }
    }
});

By setting the TextView's width to 0 initially, you prevent it from changing the widths of the fragments. Then you can use a view tree observer to get the width of whatever fragment you're interested in (by looking at its root view) after layout has occurred. Finally you can set your TextView to be that exact width, which in turn will do the wrapping for you automatically.

Note that onGlobalLayout can be called multiple times and is regularly called before all of the views have been completely laid out, hence the != 0 check. You will also probably want to do some kind of check to make sure that you only set the width of the text view once, or otherwise you can get into an infinite layout loop (not the end of the world, but not good for performance).