Dialog with transparent background in Android

Question

How do I remove the black background from a dialog box in Android. The pic shows the problem.

final Dialog dialog = new Dialog(Screen1.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.themechanger); 

Answer 1

Attention :

don't use builder for change background

 Dialog dialog = new Dialog.Builder(MainActivity.this)
                            .setView(view)
                            .create();
 dialog.show();dialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);

change to

Dialog dialog = new Dialog(getActivity());
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(view);
dialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);
mDialog.show();

When using Dialog.builder - Its not giving getwindow() option in it.

Answer 2

use this code it's works with me :

    Dialog dialog = new Dialog(getActivity(),android.R.style.Theme_Translucent_NoTitleBar);
    dialog.show();

Answer 3

One issue I found with all the existing answers is that the margins aren't preserved. This is because they all override the android:windowBackground attribute, which is responsible for margins, with a solid color. However, I did some digging in the Android SDK and found the default window background drawable, and modified it a bit to allow transparent dialogs.

First, copy /platforms/android-22/data/res/drawable/dialog_background_material.xml to your project. Or, just copy these lines into a new file:

<inset xmlns:android="http://schemas.android.com/apk/res/android"
    android:inset="16dp">
    <shape android:shape="rectangle">
        <corners android:radius="2dp" />
        <solid android:color="?attr/colorBackground" />
    </shape>
</inset>

Notice that android:color is set to ?attr/colorBackground. This is the default solid grey/white you see. To allow the color defined in android:background in your custom style to be transparent and show the transparency, all we have to do is change ?attr/colorBackground to @android:color/transparent. Now it will look like this:

<inset xmlns:android="http://schemas.android.com/apk/res/android"
    android:inset="16dp">
    <shape android:shape="rectangle">
        <corners android:radius="2dp" />
        <solid android:color="@android:color/transparent" />
    </shape>
</inset>

After that, go to your theme and add this:

<style name="MyTransparentDialog" parent="@android:style/Theme.Material.Dialog">
    <item name="android:windowBackground">@drawable/newly_created_background_name</item>
    <item name="android:background">@color/some_transparent_color</item>
</style>

Make sure to replace newly_created_background_name with the actual name of the drawable file you just created, and replace some_transparent_color with the desired transparent background.

After that all we need to do is set the theme. Use this when creating the AlertDialog.Builder:

    AlertDialog.Builder builder = new AlertDialog.Builder(this, R.style.MyTransparentDialog);

Then just build, create, and show the dialog as usual!

Answer 4

In my case solution works like this:

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

And Additionally in Xml of custom dialog:

android:alpha="0.8"