android - 自定义 View 不膨胀

Question

我正在尝试通过 xml 创建我的自定义 View ，但屏幕不显示我的 View ，因为它没有膨胀。我的自定义 View xml 如下:

 <?xml version="1.0" encoding="utf-8"?>
<ViewSwitcher xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/profileSwitcher"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FFFFFF" >

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >

        <ImageView
            android:id="@+id/imgAdvertise"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:src="@android:drawable/btn_minus" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center_horizontal" >

        <TextView
            android:id="@+id/txtAdvertise"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:text="asdas" />
    </LinearLayout>

</ViewSwitcher>

我有我的自定义 View 类:

public class MyCustomView extends View{

    TextView textAdvertise;
    ImageView imageAdvertise;
    View view;
    ViewSwitcher switcher ;

    public MyCustomView(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub

        LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (layoutInflater != null) {
            view = layoutInflater.inflate(R.layout.main, null);

        }

        initialize();
    }

    public void initialize() {
        // TODO Auto-generated method stub

        textAdvertise = (TextView) view.findViewById(R.id.txtAdvertise);
        imageAdvertise = (ImageView) view.findViewById(R.id.imgAdvertise);
        switcher = (ViewSwitcher) view.findViewById(R.id.profileSwitcher);
        startAnimation();

    }

    public void startAnimation() {
        // TODO Auto-generated method stub

        new Thread() {
            public void run() {

                for (;;) {
                    try {

                        Thread.sleep(2000);
                        hRefresh.sendEmptyMessage(5);
                    } catch (Exception e) {
                    }
                }
            }
        }.start();
    }

    Handler hRefresh = new Handler() {
        public void handleMessage(Message msg) {
            switch (msg.what) {
            case 5:
                switcher.showNext();
                // To go back to the first view, use switcher.showPrevious()
                break;
            default:
                break;
            }
        }
    };

}

在我必须显示 View 的基本 xml 布局中，是一个按钮，而我的 View 为:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<Button
    android:id="@+id/button1"
    android:layout_width="fill_parent"
    android:layout_height="0dp"
    android:text="Button" 
    android:layout_weight="1"/>

<com.example.viewswitcher.MyCustomView 
    android:id="@+id/MyView"
    android:layout_width="fill_parent"
    android:layout_height="0dp"
    android:layout_weight="1"

    />

谁能告诉我这是怎么回事？

Answer 1

您什么也看不到，因为 MyCustomView 没有您编写的任何内容。首先，我将使用 ViewGroups 子项之一而不是 View(如 LinearLayout、RelativeLayout 等):

public class MyCustomView extends LinearLayout {

    TextView textAdvertise;
    ImageView imageAdvertise;
    View view;
    ViewSwitcher switcher ;

    public MyCustomView(Context context, AttributeSet attrs) {
        super(context);
    }

    public MyCustomView(Context context, AttributeSet attrs) {
        super(context, attrs);
        LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (layoutInflater != null) {
            view = layoutInflater.inflate(R.layout.main, this, true);
        }
        initialize();
    }

     public MyCustomView(Context context, AttributeSet attrs, int theme) {
         super(context, attrs, theme);
     }
// ...