Change the background color of a pop-up dialog

I wrote android code that shows a pop-up dialog but I want to change the background color from black to white , and then the color of the writing.

This is the dialog's code:

mPrefs = PreferenceManager.getDefaultSharedPreferences(this);

    Boolean welcomeScreenShown = mPrefs.getBoolean(welcomeScreenShownPref, false);

    if (!welcomeScreenShown) {


        String whatsNewText = getResources().getString(R.string.Text);
        new AlertDialog.Builder(this).setMessage(whatsNewText).setPositiveButton(
                R.string.ok, new DialogInterface.OnClickListener(){
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
            }
        }).show();
        SharedPreferences.Editor editor = mPrefs.edit();
        editor.putBoolean(welcomeScreenShownPref, true);
        editor.commit(); // Very important to save the preference
    }

To expand on @DaneWhite's answer, you don't have to rely on the built-in themes. You can easily supply your own style:

<style name="MyDialogTheme" parent="Theme.AppCompat.Light.Dialog.Alert">
    <item name="android:background">@color/myColor</item>
</style>

and then apply it in the Builder constructor:

Java:

AlertDialog alertDialog = new AlertDialog.Builder(getContext(), R.style.MyDialogTheme)
        ...
        .create();

Kotlin:

var alertDialog = AlertDialog.Builder(context, R.style.MyDialogTheme)
        ...
        .create()

This should work whether you are using android.support.v7.app.AlertDialog or android.app.AlertDialog

This also works better than @DummyData's answer because you don't resize the dialog. If you set window's background drawable you overwrite some existing dimensional information and get a dialog that is not standard width.

If you set background on theme and the set the theme on dialog you'll end up with a dialog that is colored how you want but still the correct width.

If you just want a light theme and aren't particular about the specific color, then you can pass a theme id to the AlertDialog.Builder constructor.

AlertDialog.Builder(this, AlertDialog.THEME_HOLO_LIGHT)...

or

AlertDialog.Builder(this, AlertDialog.THEME_DEVICE_DEFAULT_LIGHT)...

Credit goes to Sushil

Create your AlertDialog as usual:

AlertDialog.Builder dialog = new AlertDialog.Builder(getContext());
Dialog dialog = dialog.create();
dialog.show();

After calling show() on your dialog, set the background color like this:

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

To change the background color of all dialogs and pop-ups in your app, use colorBackgroundFloating attribute.

<style name="MyApplicationTheme" parent="@style/Theme.AppCompat.NoActionBar">
...
<item name="colorBackgroundFloating">
    @color/background</item>
<item name="android:colorBackgroundFloating" tools:targetApi="23">
    @color/background</item>
...
</style>

Documentation:

colorBackgroundFloating

With the Material Components Library you can just use the default MaterialAlertDialogBuilder:

    new MaterialAlertDialogBuilder(AlertDialogActivity.this,
        R.style.ThemeOverlay_MaterialComponents_MaterialAlertDialog_Background)
        .setTitle("Dialog")
        .setMessage("Message...  ....")
        .setPositiveButton("Ok", /* listener = */ null)
        .show();

where the theme overlay ThemeOverlay_MaterialComponents_MaterialAlertDialog_Background is:

  <!-- Alert Dialog -->
  <style name="ThemeOverlay.MaterialComponents.MaterialAlertDialog_Background" parent="@style/ThemeOverlay.MaterialComponents.MaterialAlertDialog">
    <!-- Background Color-->
    <item name="android:background">@color/.....</item>
    <!-- Text Color for title and message -->
    <item name="colorOnSurface">@color/......</item>
    <!-- Style for positive button -->
    <item name="buttonBarPositiveButtonStyle">@style/PositiveButtonStyle</item>
    <!-- Style for negative button -->
    <item name="buttonBarNegativeButtonStyle">@style/NegativeButtonStyle</item>
  </style>

  <style name="PositiveButtonStyle" parent="@style/Widget.MaterialComponents.Button">
    <!-- text color for the button -->
    <item name="android:textColor">@color/.....</item>
    <!-- Background tint for the button -->
    <item name="backgroundTint">@color/primaryDarkColor</item>
  </style>

For any dialog called myDialog, after calling myDialog.show(); you can call:

myDialog.getWindow().getDecorView().getBackground().setColorFilter(new LightingColorFilter(0xFF000000, CUSTOM_COLOR));

where CUSTOM_COLOR is in 8-digit hex format, ex. 0xFF303030. Here, FF is the alpha value and the rest is the color value in hex.

You can create a custom alertDialog and use a xml layout. in the layout, you can set the background color and textcolor.

Something like this:

Dialog dialog = new Dialog(this, android.R.style.Theme_Translucent_NoTitleBar);
LayoutInflater inflater = (LayoutInflater)ActivityName.this.getSystemService(LAYOUT_INFLATER_SERVICE);
View layout = inflater.inflate(R.layout.custom_layout,(ViewGroup)findViewById(R.id.layout_root));
dialog.setContentView(view);

I order to change the dialog buttons and background colors, you will need to extend the Dialog theme, eg.:

<style name="MyDialogStyle" parent="android:Theme.Material.Light.Dialog.NoActionBar">
    <item name="android:buttonBarButtonStyle">@style/MyButtonsStyle</item>
    <item name="android:colorBackground">@color/white</item>
</style>

<style name="MyButtonsStyle" parent="Widget.AppCompat.Button.ButtonBar.AlertDialog">
    <item name="android:textColor">@color/light.blue</item>
</style>

After that, you need to pass this custom style to the dialog builder, eg. like this:

AlertDialog.Builder(requireContext(), R.style.MyDialogStyle)

If you want to change the color of the text inside the dialog, you can pass a custom view to this Builder:

AlertDialog.Builder.setView(View)

or

AlertDialog.Builder.setView(@LayoutResource int)

You can create a shape XML in drawable

<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <solid android:color="@color/white" />
</shape>

Add this line after creating an alert dialog

alertDialog.getWindow().setBackgroundDrawable(ContextCompat.getDrawable(ATextActivity.this,R.drawable.color_drawable));

If you do not want to create XML you can try this below code

Create a drawable of color

ColorDrawable colorDrawable = new ColorDrawable(ContextCompat.getColor(this, R.color.white));

alertDialog.getWindow().setBackgroundDrawable(colorDrawable);

Use setInverseBackgroundForced(true) on the alert dialog builder to invert the background.