Java 如何在android studio中使用transition更改圆形按钮的颜色

我是android studio的一个非常基础的初学者，我一直在为切换按钮添加过渡。因为它是圆形的，一旦我改变背景颜色，它就会变成正方形。如果有人能帮我，我将不胜感激。谢谢

这是我的按钮布局XML

<ToggleButton
        android:id="@+id/button2"
        android:layout_width="279dp"
        android:layout_height="279dp"
        android:layout_centerInParent="true"
        android:background="@drawable/roundcircle"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.012"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

---

您可以直接在xml中定义一个

TransitionDrawable

，例如button_bg.xml，如下所示

<?xml version="1.0" encoding="utf-8"?>
<transition xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape android:shape="oval">
            <solid android:color="#ff0000"/>
        </shape>
    </item>
    <item>
        <shape android:shape="oval">
            <solid android:color="#56ff00"/>
        </shape>
    </item>

</transition>

---

工作得很有魅力。谢谢！

public class MainActivity extends AppCompatActivity {

    private ToggleButton Remote;

    private TextView Text;

    DatabaseReference database;

    TransitionDrawable transitiondrawable;

    ColorDrawable[] BackGroundColor = {
            new ColorDrawable(Color.parseColor("#ff0000")),
            new ColorDrawable(Color.parseColor("#56ff00"))
    };


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

        Remote = (ToggleButton) findViewById(R.id.toggleButton);

        Button AppEffect = (Button) findViewById(R.id.button2);

        transitiondrawable = new TransitionDrawable(BackGroundColor);

        AppEffect.setBackground(transitiondrawable);

        Remote.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                if (isChecked){

                    transitiondrawable.startTransition(3000);

                }
                else{

                    transitiondrawable.startTransition(3000);
                }
            }
        });
    }
}

<?xml version="1.0" encoding="utf-8"?>
<transition xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape android:shape="oval">
            <solid android:color="#ff0000"/>
        </shape>
    </item>
    <item>
        <shape android:shape="oval">
            <solid android:color="#56ff00"/>
        </shape>
    </item>

</transition>

transitiondrawable = (TransitionDrawable) getResources().getDrawable(R.drawable.button_bg);