How do I create a transparent Activity on Android?

Question

I want to create a transparent Activity on top of another activity.

How can I achieve this?

Answer 1

I just did two things, and it made my activity transparent. They are below.

1. In the manifest file I just added the below code in the activity tag.

   android:theme="@android:style/Theme.Translucent.NoTitleBar.Fullscreen"
   

2. And I just set the background of the main layout for that activity as "#80000000". Like

   android:background="#80000000"
   

It perfectly works for me.

Answer 2

It goes like this:

<activity android:name=".usual.activity.Declaration" android:theme="@android:style/Theme.Translucent.NoTitleBar" />

Answer 3

Along with the gnobal's above solution, I had to set alpha to 0 in the layout file of that particular activity, because on certain phone (Redmi Narzo 20 pro running on Android 10) a dialog portion of the screen was showing with the screen that was supposed to be transparent. For some reason the windowIsFloating was causing this issue, but on removing it I wasn't getting the desired output.

Steps:

1. Add the following in the style.xml located under res > values > styles.xml

    <style name="Theme.Transparent" parent="android:Theme">
      <item name="android:windowIsTranslucent">true</item>
      <item name="android:windowBackground">@android:color/transparent</item>
      <item name="android:windowContentOverlay">@null</item>
      <item name="android:windowNoTitle">true</item>
      <item name="android:windowIsFloating">true</item>
      <item name="android:backgroundDimEnabled">false</item>
      <item name="android:colorBackgroundCacheHint">@null</item>
    </style>
   

   
   

2. Set the theme of the activity with the above style in AndroidManifest.xml

   <activity
         android:name=".activityName"
         android:theme="@style/Theme.Transparent"/>
   

   
   

3. Open your layout file of the activity on which you applied the above style and set it's alpha value to 0 (android:alpha="0") for the parent layout element.

   <?xml version="1.0" encoding="utf-8"?>
   <androidx.constraintlayout.widget.ConstraintLayout 
       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"
       android:alpha="0">
   
     <WebView        
           android:layout_width="match_parent"
           android:layout_height="match_parent"
           android:alpha="0"/>
   
   </androidx.constraintlayout.widget.ConstraintLayout>
   

Please Note: You'll have to extend you activity using Activity() class and not AppCompatActivity for using the above solution.

Answer 4

In the styles.xml:

<style name="Theme.AppCompat.Translucent" parent="Theme.AppCompat.NoActionBar">
    <item name="android:background">#33000000</item> <!-- Or any transparency or color you need -->
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowBackground">@android:color/transparent</item>
    <item name="android:colorBackgroundCacheHint">@null</item>
    <item name="android:windowIsTranslucent">true</item>
    <item name="android:windowAnimationStyle">@android:style/Animation</item>
</style>

In the AndroidManifest.xml:

<activity
    android:name=".WhateverNameOfTheActivityIs"
    android:theme="@style/Theme.AppCompat.Translucent">
    ...
</activity>