In this article, we will develop an Android application which changes the text color of an EditText widget when a valid color is entered in the EditText.
This application is developed in Eclipse ( 4.2.1 ) with ADT plugin ( 21.0.0 ) and Android SDK ( 21.0.0 ).
1. Create a new Android application project namely “TextColorEditTextProgramatically”
Figure 1 : Creating new Android Application project
2. Configure the project
Figure 2 : Configuring the Android application project
3. Design Application launcher icon
Figure 3 : Design the application launcher icon
4. Create a blank activity
Figure 4 : Create a blank activity
5. Enter MainActivity details
Figure 5 : Enter MainActivity details
6. Delete Android’s support library from this project, if exists ( Optional Step )
By default Eclipse ( 4.2.1) adds Android Support Library to Android application project. For this application, we don’t need to use this support library. So the library file libs/android-support-v4.jar may be removed manually via ProjectExplorer by simply right click on the file and then clicking the menu item “delete”
7. Update the file res/values/strings.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">TextColorEditTextProgramatically</string>
<string name="hello_world">Hello world!</string>
<string name="menu_settings">Settings</string>
<string name="hnt_color">Enter color ( eg : #a2b5cf )</string>
</resources>
8. Update the file res/layout/activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<EditText
android:id="@+id/et_color"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:hint="@string/hnt_color"
android:inputType="text" />
</RelativeLayout>
9. Update the file src/in/wptrafficanalyzer/textcoloredittextprogramatically/MainActivity.java
package in.wptrafficanalyzer.textcoloredittextprogramatically;
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.inputmethod.EditorInfo;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.TextView.OnEditorActionListener;
import android.widget.Toast;
public class MainActivity extends Activity {
EditText etColor;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Getting reference to EditText
etColor = (EditText) findViewById(R.id.et_color);
// Setting an EditorActionListener for the EditText
etColor.setOnEditorActionListener(new OnEditorActionListener() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
// Getting the user input text
String color = v.getText().toString();
try{
// If user presssed Done button of the keyboard
if(actionId == EditorInfo.IME_ACTION_DONE){
// Changing the color the text
etColor.setTextColor(Color.parseColor(color));
// Showing a Toast message
Toast.makeText(getBaseContext(), v.getText(), Toast.LENGTH_SHORT).show();
}
}catch(IllegalArgumentException e){
Toast.makeText(getBaseContext(), "Invalid color. Enter color as eg : #a2fa34 ", Toast.LENGTH_SHORT).show();
}catch(Exception e){
Toast.makeText(getBaseContext(), "Invalid, enter color as eg : #a2fa34 ", Toast.LENGTH_SHORT).show();
}
// return false, means , continue to other handlers
return false;
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}
10. Screenshot of the application in execution
Figure 6 : Entering Hexa Decimal value corresponding to a color
Figure 7 : Color of the text is changed after entering the color code
11. Download source code
I am George Mathew, working as software architect and Android app developer at wptrafficanalyzer.in
You can hire me on hourly basis or on project basis for Android applications development.
For hiring me, please mail your requirements to info@wptrafficanalyzer.in.
My other blogs
store4js.blogspot.com
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