java - ViewGroup 未在 Android Studio 中解析

Question

我正在使用 Android Studio 创建一个小型动画应用。当按下按钮时，图像应根据特定动画工作。

viewGroup = (viewGroup)findViewById(R.id.ViewGroup); 行有错误

它显示“无法解析符号 ViewGroup”。我键入 Alt+Enter 并选择了一个解决方案。但什么也没发生。

public class MainActivity extends Activity {
private ViewGroup viewGroup;
private ImageView imageView, imageView2, imageView3,imageView4,imageView5,imageView6,imageView7,imageView8,imageView9,imageView10,imageView11,imageView12;
private Button button,button1;

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

    viewGroup=(viewGroup)findViewById(R.id.ViewGroup);

    imageView= (ImageView) findViewById(R.id.imageView);
    imageView2= (ImageView) findViewById(R.id.imageView2);
    imageView3= (ImageView) findViewById(R.id.imageView3);
    imageView4= (ImageView) findViewById(R.id.imageView4);
    imageView5= (ImageView) findViewById(R.id.imageView5);
    imageView6=(ImageView) findViewById(R.id.imageView6);
    imageView7=(ImageView) findViewById(R.id.imageView7);
    imageView8=(ImageView) findViewById(R.id.imageView8);
    imageView9=(ImageView) findViewById(R.id.imageView9);
    imageView10=(ImageView) findViewById(R.id.imageView10);
    imageView11=(ImageView) findViewById(R.id.imageView11);
    imageView12=(ImageView) findViewById(R.id.imageView12);



    button = (Button)findViewById(R.id.button);
    button1=(Button)findViewById(R.id.button1);


    button1.setOnClickListener(new View.OnClickListener(){
        public void onClick(View v){
            TransitionManager.beginDelayedTransition(viewGroup, new Fade());
            fade(imageView, imageView2, imageView3,imageView4,imageView5,imageView6);
        }

    });

    button.setOnClickListener(new View.OnClickListener(){
        public void onClick(View v) {
            TransitionManager.beginDelayedTransition(viewGroup, new Slide());
            toggle(imageView7,imageView8,imageView9,imageView10,imageView11,imageView12);
        }
    });}



private static void toggle(View... views) {
    for (View v : views) {
        boolean isVisible = v.getVisibility() == View.VISIBLE;
        v.setVisibility(isVisible ? View.INVISIBLE :
                View.VISIBLE);
    }
}

private static void fade(View... views) {
    for (View v : views) {
        boolean isVisible = v.getVisibility() == View.VISIBLE;
        v.setVisibility(isVisible ? View.INVISIBLE :
                View.VISIBLE);
    }

这是我的 activity_main xml

<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:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity"
android:id="@+id/myAniLayout">

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="New Button"
    android:id="@+id/button"
    android:layout_alignParentBottom="true"
    android:layout_alignParentStart="true"
    android:layout_marginBottom="44dp" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="New Button"
    android:id="@+id/button1"
    android:layout_alignBottom="@+id/button"
    android:layout_alignParentEnd="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:src="@mipmap/ic_launcher" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView2"
    android:src="@mipmap/ic_launcher"
    android:layout_below="@+id/imageView"
    android:layout_alignParentStart="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView3"
    android:src="@mipmap/ic_launcher"
    android:layout_alignTop="@+id/imageView2"
    android:layout_alignParentEnd="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView4"
    android:src="@mipmap/ic_launcher"
    android:layout_below="@+id/imageView2"
    android:layout_centerHorizontal="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView5"
    android:src="@mipmap/ic_launcher"
    android:layout_below="@+id/imageView4"
    android:layout_alignParentStart="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView6"
    android:src="@mipmap/ic_launcher"
    android:layout_below="@+id/imageView4"
    android:layout_alignParentEnd="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView7"
    android:layout_centerVertical="true"
    android:layout_centerHorizontal="true"
    android:src="@android:drawable/star_big_on" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView8"
    android:src="@android:drawable/star_big_on"
    android:layout_below="@+id/imageView7"
    android:layout_alignParentStart="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView9"
    android:src="@android:drawable/star_big_on"
    android:layout_below="@+id/imageView7"
    android:layout_alignParentEnd="true" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView10"
    android:src="@android:drawable/star_big_on"
    android:layout_below="@+id/imageView9"
    android:layout_alignStart="@+id/button1" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView11"
    android:src="@android:drawable/star_big_on"
    android:layout_below="@+id/imageView8"
    android:layout_alignEnd="@+id/button" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView12"
    android:src="@android:drawable/star_big_on"
    android:layout_above="@+id/button"
    android:layout_alignStart="@+id/imageView4" />

Answer 1

你的 logcat 显示

"Cannot resolve symbol 'ViewGroup'"

 viewGroup=(viewGroup)findViewById(R.id.ViewGroup); // (ViewGroup)

1. viewGroup 不在您的 XML 中声明

2. (viewGroup) 必须是 (ViewGroup) 。 ( View 组)

The ViewGroup class is a subclass of the View class. ViewGroup instances work as containers for View instances to group View instances together.

http://developer.android.com/intl/es/reference/android/view/ViewGroup.html