Android change shape solid color programmatically

Change Shape Solid Color Programmatically in Android Kotlin.

In the shape drawable xml-file you can set custom solid color with the attribute <solid android:color="@android:color/holo_purple" /> but to change the shape drawable solid color in runtime/dynamically. There is need to Change solid color of the shape drawable in android programmatically, you can edit Solid Color of a shape drawable xml-file in Android programmatically using GradientDrawable.setColor(int) method which change tint of solid color of shape drawable.

Here, TextView is set with shape drawable background. This example changes android TextView background - shape drawable solid color to grey from purple color.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:orientation="vertical"
    android:layout_gravity="center_horizontal"
    android:gravity="center_horizontal"
    tools:context=".MainActivity">

    <Button
        android:layout_marginTop="10dp"
        android:id="@+id/button"
        android:text="Change Solid Color"
        android:layout_width="wrap_content"
        android:layout_marginBottom="30dp"
        android:layout_height="wrap_content" />

    <TextView
        android:layout_below="@+id/button"
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="TextView "
        android:padding="10dp"
        android:textColor="@android:color/black"
        android:background="@drawable/rounded_border"
        />
</RelativeLayout>

res/drawable/rounded_corners

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
    <solid android:color="@android:color/holo_purple" />
    <stroke
        android:width="3dp"
        android:color="@android:color/holo_orange_dark" />
    <corners android:radius="7dp" />
</shape>

MainActivity.java

Kotlin Code

package com.example.changeshapesolidcolor

import android.graphics.Color
import android.graphics.drawable.GradientDrawable
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        button.setOnClickListener {
            //change the shape solid color in xml programmatically Kotlin
            val gradientDrawable = (textView.getBackground() as GradientDrawable).mutate()
            (gradientDrawable as GradientDrawable).setColor(Color.LTGRAY)
        }
    }
}

Android Code

package com.example.changeshapesolidcolor;

import android.content.res.Resources;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.GradientDrawable;
import android.support.graphics.drawable.VectorDrawableCompat;
import android.support.v4.graphics.drawable.DrawableCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    Button button;
    TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textView=findViewById(R.id.textView);
        button=findViewById(R.id.button);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                //change the shape solid color programmatically in Android GradientDrawable gradientDrawable= ((GradientDrawable) textView.getBackground()).mutate();
                 ((GradientDrawable)gradientDrawable ).setColor(Color.LTGRAY);
            }
        });
    }
}

Default Color of the Shape Drawable Solid Color is holo_purple color before button click

Android Text view background Shape Drawable Solid Color Changed to Gray Color on button click

More on GradientDrawable.setColor(int) method

setColor method added Added in API level 1

public void setColor (int argb)

Use: Changes this drawable to use a single color instead of a gradient.

Note: changing color will affect all instances of a drawable loaded from a resource. It is recommended to invoke mutate() before changing the color.