Setting device wallpaper to be a gradient background (Android Studio)

Question

I have created a gradient drawable in the drawable folder. It is a shape in an xml file.

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item>
        <shape android:shape="rectangle" >
            <gradient
                android:angle="45"
                android:centerColor="@color/centerColor"
                android:endColor="@color/endColor"
                android:startColor="@color/startColor" />
        </shape>
    </item>
</selector>

I am trying to set the gradient as the wallpaper for the device using the app when a certain button is clicked. Is this even possible?

Thanks in advance. :)

Java Code:

public void onClick(View v) {
//                WallpaperManager myWallpaperManager  = WallpaperManager.getInstance(getApplicationContext());
                InputStream is = getResources().openRawResource(R.raw.gradient);
                Bitmap b = BitmapFactory.decodeStream(is);

                try {
//                    myWallpaperManager.setBitmap(+ R.drawable.gradient);
                    getApplicationContext().setWallpaper(b);
                    Toast.makeText(getApplicationContext(),"Wallpaper updated", Toast.LENGTH_SHORT ).show();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

            }

you will likely have to draw this gradient on the bitmap, save it, and only then - set the wallpaper. I don't believe you can set the XML drawable as a wallpaper — Vladyslav Matviienko, Jan 09 '19 at 06:44
I tried converting the drawable to bitmap. The wallpaper did update but it only displayed the first color of the gradient... :) — Edwin Youbirdmurali, Jan 09 '19 at 06:53
Probably I did. But, I can't seem to find the root of the problem... haha — Edwin Youbirdmurali, Jan 09 '19 at 06:55
your drawable has no size. You need to create a bitmap of some size, and draw the drawable on it. — Vladyslav Matviienko, Jan 09 '19 at 06:58

sushildlh · Answer 1 · 2019-01-09T06:46:25.500

1

Is this even possible?

Yes, it is possible.

Include this permission in your manifest.

Create raw folder in your res folder and add that gradient inside the raw folder

And use this code in your application.

       WallpaperManager myWallpaperManager  = WallpaperManager.getInstance(getApplicationContext());
        try {
            myWallpaperManager.setResource(R.raw.your_gradient_drawable);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

edited Jan 09 '19 at 06:46

answered Jan 09 '19 at 06:03

sushildlh

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have you tried this https://stackoverflow.com/a/32038517/5305430 with your raw file ? – sushildlh Jan 09 '19 at 06:19
Yup. I tried placing the gradient.xml in the "raw" folder to no avail. I do not have to use InputStream right? :) – Edwin Youbirdmurali Jan 09 '19 at 06:39
I tried that too. InputStream is = getResources().openRawResource(R.raw.gradient); – Edwin Youbirdmurali Jan 09 '19 at 06:41
Sure. I have included the gradient and a snippet of the java code above. :) – Edwin Youbirdmurali Jan 09 '19 at 06:50

Setting device wallpaper to be a gradient background (Android Studio)

1 Answers1