I am creating a custom class CustomButton that represents a Button with a custom style. CustomButton's style is programatically retrieved from styles.xml and set. A CustomButton is programatically added to the app's layout. However, when I run an app, even though the background color is correct (light blue), the color of the text is incorrect (should be red or #ff0000):

Below is my code:

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:background="#ffffff"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@ id/tile_list"
        android:orientation="vertical">
    </LinearLayout>
</LinearLayout>

styles.xml:

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>


        <!-- Removes the TitleBar from the display -->
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>
    </style>

    <style name="CustomButtonStyle">
        <item name="android:background">#b3e0ff</item>
        <item name="android:textColor">#ff0000</item>
    </style>
</resources>

MainActivity.java:

package com.example.stackoverflowquestion;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.LinearLayout;

public class MainActivity extends AppCompatActivity {

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

        // Retrieve the Equation Lists from secondary storage and display them.
        CustomButton tile1 = new CustomButton(this);
        LinearLayout tileListLayout = findViewById(R.id.tile_list);
        tileListLayout.addView(tile1);
    }
}

CustomButton.java:

package com.example.stackoverflowquestion;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.util.AttributeSet;

import androidx.appcompat.widget.AppCompatButton;

public class CustomButton extends AppCompatButton {
    private Context context;

    public CustomButton(Context context) {
        super(context);
        this.context = context;

        // Set the style of the Tile.
        this.setStyle();
    }

    public CustomButton(Context context, AttributeSet attrs) {
        super(context, attrs);

        // Set the style of the Tile.
        this.setStyle();
    }

    // Set the styling of the Tile, retrieved from the defined style in styles.xml.
    @SuppressWarnings("ResourceType")
    private void setStyle() {
        int[] attributesToRetrieve = {android.R.attr.background, android.R.attr.textColor};
        TypedArray attributeValues = this.context.obtainStyledAttributes(R.style.CustomButtonStyle,
                                                                         attributesToRetrieve);

        // Set the background.
        this.setBackgroundColor(attributeValues.getColor(0, Color.WHITE));

        // Set the text color.
        this.setTextColor(attributeValues.getColor(1, Color.BLACK));

        this.setText("Custom Button");
    }
}

build.gradle (app):

apply plugin: 'com.android.application'

android {
    compileSdkVersion 31
    buildToolsVersion "29.0.2"
    defaultConfig {
        applicationId "com.example.stackoverflowquestion"
        minSdkVersion 26
        targetSdkVersion 31
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
}

CodePudding user response：