Dialog with transparent background in Android

Add this code

 dialog.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));

Or this one instead:

dialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);

TL;DR; You just need two things, firstly in your style do something like:

<item name="android:windowIsTranslucent">true</item>
<item name="android:windowBackground">@android:color/transparent</item>

Secondly, make 100% sure said style gets applied to your dialog (maybe by passing to constructor).

Full example

<style name="NewDialog">
    <item name="android:windowFrame">@null</item>
    <item name="android:windowBackground">@android:color/transparent</item>
    <item name="android:windowIsFloating">true</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowTitleStyle">@null</item>
    <item name="android:windowAnimationStyle">@android:style/Animation.Dialog</item>
    <item name="android:windowSoftInputMode">stateUnspecified|adjustPan</item>
    <item name="android:backgroundDimEnabled">false</item>
    <item name="android:background">@android:color/transparent</item>
</style>

Use in Java:

Dialog dialog = new Dialog(this, R.style.NewDialog);

I hope helps you !

I've faced the simpler problem and the solution i came up with was applying a transparent bachground THEME. Write these lines in your styles

    <item name="android:windowBackground">@drawable/blue_searchbuttonpopupbackground</item>
</style>
<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>
</style>

And then add

android:theme="@style/Theme.Transparent"

in your main manifest file , inside the block of the dialog activity.

Plus in your dialog activity XML set

 android:background= "#00000000"