How can I get an Android TableLayout to fill the screen?

Question

I'm battling with Android's awful layout system. I'm trying to get a table to fill the screen (simple right?) but it's ridiculously hard.

I got it to work somehow in XML like this:

<?xml version="1.0" encoding="utf-8"?>

<TableLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_height="fill_parent" android:layout_width="fill_parent">
<TableRow android:layout_height="fill_parent" android:layout_width="fill_parent" android:layout_weight="1">
<Button android:text="A" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_weight="1"/>
<Button android:text="B" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_weight="1"/>
</TableRow>
<TableRow android:layout_height="fill_parent" android:layout_width="fill_parent" android:layout_weight="1">
<Button android:text="C" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_weight="1"/>
<Button android:text="D" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_weight="1"/>
</TableRow>

However I can not get it to work in Java. I've tried a million combinations of the LayoutParams, but nothing ever works. This is the best result I have which only fills the width of the screen, not the height:

    table = new TableLayout(this);
    // Java. You suck.
    TableLayout.LayoutParams lp = new TableLayout.LayoutParams(
                                    ViewGroup.LayoutParams.FILL_PARENT,
                                    ViewGroup.LayoutParams.FILL_PARENT);
    table.setLayoutParams(lp); // This line has no effect! WHYYYY?!
    table.setStretchAllColumns(true);
    for (int r = 0; r < 2; ++r)
    {
        TableRow row = new TableRow(this);
        for (int c = 0; c < 2; ++c)
        {
            Button btn = new Button(this);
            btn.setText("A");
            row.addView(btn);
        }
        table.addView(row);
    }

Obviously the Android documentation is no help. Anyone have any ideas?

Answer 1

There are two mistakes in the above discussion.

1. It is possible to programatically set the weight by specifying TableLayout.LayoutParams and TableRow.LayoutParams and using the appropriate constructor, e.g.

   TableLayout.LayoutParams rowInTableLp = new TableLayout.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT, 1.0f);
   

2. A widget must have the LayoutParams of its parent. Therefore, the rows must use TableLayout.LayoutParams.

This gives you the following working version of your initial code:

TableLayout table = new TableLayout(this);
// Java. You succeed!
FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
        ViewGroup.LayoutParams.FILL_PARENT,
        ViewGroup.LayoutParams.FILL_PARENT);
table.setLayoutParams(lp);
table.setStretchAllColumns(true);

TableLayout.LayoutParams rowLp = new TableLayout.LayoutParams(
        ViewGroup.LayoutParams.FILL_PARENT,
        ViewGroup.LayoutParams.FILL_PARENT,
        1.0f);
TableRow.LayoutParams cellLp = new TableRow.LayoutParams(
        ViewGroup.LayoutParams.FILL_PARENT,
        ViewGroup.LayoutParams.FILL_PARENT,
        1.0f);
for (int r = 0; r < 2; ++r)
{
    TableRow row = new TableRow(this);
    for (int c = 0; c < 2; ++c)
    {
        Button btn = new Button(this);
        btn.setText("A");
        row.addView(btn, cellLp);
    }
    table.addView(row, rowLp);
}
setContentView(table);

Thanks to Romain Guy's comment on Android developer's forum for the solution.