Android view not shown after addView method

Question

I have an issue with ViewGroup.addView() method. I use this code to add new view to my layout:

TalbeLayout parent = (TableLayout)findViewById(R.id.this_does_not_matter);
parent.removeAllViews(); //this view group contains something at start
TextView tv = new TextView(this);
tv.setText("some text");
TableLayout.LayoutParams lp = new TableLayout.LayoutParams(TableLayout.LayoutParams.MATCH_PARENT, TableLayout.LayoutParams.WRAP_CONTENT);
tv.setLayoutParams(lp);
parent.addView(tv);

And after that I cant see my TextView. More than that, parent.getChildCount() returns correct values (1 if I try to add one child). In onClick() method of parent view I try to get width and height of TextView and all of this equals to 0. Calling requestLayout(), invalidate() and measure(500, 50) for TableView and parent has no effect. I even try to add new view with the help of view.post(Runnable), although this code is executed in UI thread.

I confused. I really don't understand what happens. Can someone explain me what I doing wrong?

One interesting moment: setLayoutParams() has no effect. If I set params with width=500 and height=50, in onClick method I get params with width=-1 and height=-1.

Code after TableRow added:

TableLayout parent = (TalleLayout)findViewById(R.id.this_does_not_matter);
parent.removeAllViews(); //this view group contains something at start
TextView tv = new TextView(this);
tv.setText("some text");
TableLayout.LayoutParams lp = new TableLayout.LayoutParams(500, 50);
TableRow.LayoutParams tlp = new TableRow.LayoutParams(500, 50);
TableRow tr = new TableRow(this);
tr.addView(tv, tlp);
parent.addView(tr, lp);
parent.invalidate();
parent.requestLayout();

I found one more interesting thing. This Activity runs from TabHost. And "addView bug" appears only if the Activity is first selected in this TabHost. If at the first time I start Activity from another tab, all works fine.

Answer 1

I found solution. If switch off layout animation with android:animateLayoutChanges="false" all works fine. But I still have no idea why this happens. If anyone know reason of this behavior, it interesting for me.