transition-drawable不显示所有颜色

46qrfjad  于 2021-07-03  发布在  Java
关注(0)|答案(1)|浏览(281)

我试着通过点击按钮来切换背景的颜色。它显示了初始颜色(蓝色),当我点击它会变成下一种颜色(红色)。当我再次点击时,它会变回蓝色,并迅速变为红色,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,并创建了一个名为transition.xml的可绘制资源来转换。

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>
brvekthn

brvekthn1#

transitiondrawable仅支持两层
transitiondrawable是一个可以在两个可绘制资源之间交叉淡入淡出的可绘制对象。

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