How Can I Set Text Field Properties Dynamically or Statically in Android
<p>How can I set the following two properties for a text field in Android: </p>

<p>(<b>Property 1</b>) How can I set a text field that contains some text like "Enter a number" but when it is clicked the text field automatically becomes empty?</p>

<p>(<b>Property: 2</b>) Suppose I have two text fields in my application. My <em>first</em> text field only accepts integers and the <em>second</em> text field accepts text like "name, address" etcetera. But by mistakenly I enter some text like "apple" or "ball" in my first text field that only accepts numbers. </p>

<p>How can I set my <em>first</em> text field so that when I click on the <em>second</em> text field my <em>first</em> text field should show a toast message or change the color of inputed data to indicate invalid input?</p>
