Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Android

Posted by Meet Jethwa
Meet Jethwa
Courses Plus Student 234 Points

i want a code for when you tap the screen the background changes please help if not the code just tell me give me

touchtocchange

Peter Corletto
Peter Corletto
2,682 Points

Hello Meet Jethwa,

First, create a new Blank Activity, like "ColorChange" activity. Then, define your xml layout file for your MainActivity, or activity_main.xml, as follows:

RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="wrap_content" android:layout_height="wrap_content" tools:context=".MainActivity" android:id="@+id/relativeLayout">

<Button
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Tap Here to Change Background Color"
    android:id="@+id/colorChangeButton"
    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"/>

<EditText
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/colorEditText"
    android:text="Enter color"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:gravity="center_horizontal"/>

</RelativeLayout

Then, in MainActivity.java file, put the following code. The user will need to enter the color name, using an EditText, and then tap on the Button. It will then change the background color to that color. Please let me know if this helped. Thank you. Peter. Note: In the above activity_main.xml, do not forget to close the RelativeLayout tag at the end. I do not know why my posted code was cut off here.

package com.example.android.colorchange;

import android.content.Context; import android.graphics.Color; import android.os.Bundle; import android.support.v7.app.ActionBarActivity; import android.text.TextUtils; import android.view.MotionEvent; import android.view.View; import android.view.inputmethod.InputMethodManager; import android.widget.Button; import android.widget.EditText; import android.widget.RelativeLayout;

public class MainActivity extends ActionBarActivity {

private RelativeLayout relativeLayout;
private EditText colorEditText;
private Button colorChangeButton;
private String color;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    relativeLayout = (RelativeLayout) findViewById(R.id.relativeLayout);

    colorEditText = (EditText) findViewById(R.id.colorEditText);

    colorChangeButton = (Button) findViewById(R.id.colorChangeButton);

    colorEditText.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {

            // The following code clears the "Enter color" prompt displayed on the EditText
            // when the user taps it, and then displays the soft keyboard.

            InputMethodManager imm =      (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);

            if(imm != null) {
                imm.showSoftInput(colorEditText, 0);
            }

            colorEditText.requestFocus();

            colorEditText.setText("");

            return true;
        }
    });

    colorChangeButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            // The next line gets the color from the Edit Text.

            color = colorEditText.getText().toString();

            // Check if the user did not enter anything. If no entry, then alert

            if (TextUtils.isEmpty(color)) {
                colorEditText.setError("You need to enter a color!");
                return;
            }

            // The next line changes the background color to that entered color.

            relativeLayout.setBackgroundColor(Color.parseColor(color));

        }
    });

    }

}

2 Answers

Meet Jethwa
PLUS
Meet Jethwa
Courses Plus Student 234 Points
Meet Jethwa
Meet Jethwa
Courses Plus Student 234 Points

thank you so much Peter . but i dont want a button just tap on the screen and the color should change

Peter Corletto
Peter Corletto
2,682 Points
Peter Corletto
Peter Corletto
2,682 Points

I have never done it, but I checked in stackOverFlow.com and they recommend doing something like this:

yourRelativeLayout.setOnTouchListener(new View.OnTouchListener() {
@Override public boolean onTouch(View arg0, MotionEvent arg1) { // Place the change color code inside here.....

    return true;//always return true to consume event
}

});

This should make the whole relativeLayout responsive to touch, without using a button.

Also, you have to set your RelativeLayout view this attribute to true: android:clickable="true" (In the XML file).