The EditText is the standard text entry widget in Android apps. If the user needs to enter text into an app, this is the primary way for them to do that.
EditText
There are many important properties that can be set to customize the behavior of an EditText. Several of these are listed below. Check out the official text fields guide for even more input field details.
Usage
An EditText is added to a layout with all default behaviors with the following XML:
<EditText
android:id="@+id/et_simple"
android:layout_height="wrap_content"
android:layout_width="match_parent">
</EditText>
Note that an EditText is simply a thin extension of the TextView and inherits all of the same properties.
Retrieving the Value
Getting the value of the text entered into an EditText is as follows:
EditText simpleEditText = (EditText) findViewById(R.id.et_simple);
String strValue = simpleEditText.getText().toString();
Further Entry Customization
We might want to limit the entry to a single-line of text (avoid newlines):
<EditText
android:singleLine="true"
android:lines="1"
/>
You can limit the characters that can be entered into a field using the digits attribute:
<EditText
android:inputType="number"
android:digits="01"
/>
This would restrict the digits entered to just "0" and "1". We might want to limit the total number of characters with:
<EditText
android:maxLength="5"
/>
Using these properties we can define the expected input behavior for text fields.
Adjusting Colors
You can adjust the highlight background color of selected text within an EditText with the android:textColorHighlight
property:
<EditText
android:textColorHighlight="#7cff88"
/>
Displaying Placeholder Hints
You may want to set the hint for the EditText control to prompt a user for specific input with:
<EditText
...
android:hint="@string/my_hint">
</EditText>
Hints
Changing the bottom line color
Assuming you are using the AppCompat library, you can override the styles colorControlNormal, colorControlActivated, and colorControlHighlight:
<style name="Theme.App.Base" parent="Theme.AppCompat.Light.DarkActionBar">
<item name="colorControlNormal">#d32f2f</item>
<item name="colorControlActivated">#ff5722</item>
<item name="colorControlHighlight">#f44336</item>
</style>
If you do not see these styles applied within a DialogFragment, there is a known bug when using the LayoutInflater passed into the onCreateView() method.
The issue has already been fixed in the AppCompat v23 library. See this guide about how to upgrade. Another temporary workaround is to use the Activity's layout inflater instead of the one passed into the onCreateView() method:
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = getActivity().getLayoutInflater().inflate(R.layout.dialog_fragment, container);
}
Listening for EditText Input
Check out the basic event listeners cliffnotes for a look at how to listen for changes to an EditText and perform an action when those changes occur.
Displaying Floating Label Feedback
Traditionally, the EditText hides the hint message (explained above) after the user starts typing. In addition, any validation error messages had to be managed manually by the developer.
With the TextInputLayout
you can setup a floating label to display hints and error messages. You can find more details here.