过渡可绘制对象不显示所有颜色

Question

我正在尝试通过单击按钮来切换背景颜色。它显示初始颜色（蓝色），当我单击它时它会变成下一种颜色（红色）。当我再次单击时，它会变回蓝色并迅速转变为红色，而不是我的第三种颜色（白色）。我已经在 colors.xml 文件中定义了颜色，并制作了一个名为 transition.xml 文件的可绘制资源进行过渡。

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

    <item android:drawable="@color/blue_background"></item>
    <item android:drawable="@color/red_background"></item>
    <item android:drawable="@color/white"></item>
"

</transition>

public class MainActivity extends AppCompatActivity {

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

        ViewGroup layout = (ViewGroup) findViewById(R.id.main_layout);
        TransitionDrawable transition = (TransitionDrawable) layout.getBackground();
        Button button = (Button) findViewById(R.id.StartTransitionButton);

        button.setOnClickListener(new View.OnClickListener() {
                                      @Override
                                      public void onClick(View v) {
                                          transition.startTransition(500);
                                          transition.startTransition(500);
                                          transition.startTransition(500);

                                      }
                                  }
        );
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/transition"
    tools:context=".MainActivity">



    <LinearLayout
        android:id="@+id/main_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@drawable/transition"
        tools:layout_editor_absoluteX="0dp"
        tools:layout_editor_absoluteY="0dp"></LinearLayout>

Answer 1

TransitionDrawable supports only two layers

A TransitionDrawable is a drawable object that can cross-fade between the two drawable resources.

过渡可绘制对象不显示所有颜色

Transition drawable not displaying all colors

java

android

transition

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