android: how can I divide a screen exactly in two parts through XML?

In main.xml, I have a table layout that it has two buttons in the first row, and two EditTexts in the second row.

when I run the application, first column 开发者_运维知识库in smaller than the other. what should I do to divide the screen equally?

Thanks

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If you have a LinearLayout enclosing the TableLayout, you can set each element to have android:layout_weight="1". That way, each element (In your case each EditText or Button) would occupy the same amount of space.