Question

我有一个使用BoxInsetLayout的应用程序，但是圆形布局没有用完，所以我必须将其更改为WatchViewStub。

我改为代码，以便它使用圆形布局或方形布局，并且可以找到。原始布局文件中有一个WearableListView，它只是一个文件。现在它是3个文件，主要文件，圆形或方形文件。现在listview始终为null，即使没有编译时错误。

我在主要活动中的onCreate

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

    WatchViewStub stub = (WatchViewStub) findViewById(R.id.stub);
    stub.setOnLayoutInflatedListener(new WatchViewStub.OnLayoutInflatedListener() {
        @Override
        public void onLayoutInflated(WatchViewStub watchViewStub) {
            mRectangleBackground = (RelativeLayout) findViewById(R.id.rectLayout);
            mRoundBackground = (RelativeLayout) findViewById(R.id.roundLayout);

        }
    });

    WearableListView listView = (WearableListView) findViewById(R.id.list); // this is always null

    listView.setHasFixedSize(true);
    listView.setAdapter(new SportAdapter(this));
    listView.setClickListener(this);
}

我的视图选择xml文件（WatchViewStub）

<?xml version="1.0" encoding="utf-8"?>
<android.support.wearable.view.WatchViewStub 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"
app:rectLayout="@layout/view_select_square"
app:roundLayout="@layout/view_select_round"
android:keepScreenOn="true"
android:id="@+id/stub"
android:background="@color/green_forest">

</android.support.wearable.view.WatchViewStub>

方形布局

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp"
app:layout_box="all"
android:id="@+id/rectLayout">

<TextView
    android:id="@+id/text_title"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:fontFamily="sans-serif-thin"
    android:paddingBottom="5dp"
    android:text="@string/text_select_sport"
    android:textColor="@color/white"
    android:textSize="26sp" />

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/text_title"
    android:background="@color/white"
    android:padding="4dp">

    <android.support.wearable.view.WearableListView
        android:layout_centerInParent="true"
        android:id="@+id/list"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:scrollbars="none"
        android:dividerHeight="0dp"/>

</RelativeLayout>

</RelativeLayout>

每当我调用listView之类的setAdapter，setHasFixedSize时，我都会得到一个空引用错误。为什么我的listView始终为null？

这是BoxInsetLayout

时的xml文件

<?xml version="1.0" encoding="utf-8"?>
<android.support.wearable.view.BoxInsetLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:keepScreenOn="true"
android:id="@+id/parent"
android:background="@color/green_forest">

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="10dp"
    app:layout_box="all">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/text_title"
        android:text="@string/text_select_sport"
        android:textSize="26sp"
        android:textColor="@color/white"
        android:fontFamily="sans-serif-thin"
        android:layout_centerHorizontal="true"
        android:layout_alignParentTop="true"
        android:paddingBottom="5dp"/>

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        android:padding="4dp"
        android:layout_below="@+id/text_title">

        <android.support.wearable.view.WearableListView
            android:layout_centerInParent="true"
            android:id="@+id/list"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:scrollbars="none"
            android:dividerHeight="0dp"/>

    </RelativeLayout>

</RelativeLayout>

</android.support.wearable.view.BoxInsetLayout>

和任何更改之前的主要活动

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.view_select);
    WearableListView listView = (WearableListView) findViewById(R.id.list);

    listView.setHasFixedSize(true);
    listView.setAdapter(new SportAdapter(this));
    listView.setClickListener(this);
}

Answer 1

所以我通过添加另一个方法loadAdapter来解决这个问题

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


    WatchViewStub stub = (WatchViewStub) findViewById(R.id.stub);
    stub.setOnLayoutInflatedListener(new WatchViewStub.OnLayoutInflatedListener() {
        @Override
        public void onLayoutInflated(WatchViewStub watchViewStub) {
            mRectangleBackground = (RelativeLayout) findViewById(R.id.rectLayout);
            mRoundBackground = (RelativeLayout) findViewById(R.id.roundLayout);
            listView = (WearableListView) findViewById(R.id.list);
            loadAdapter();
        }
    });

}

private void loadAdapter() {
    listView.setHasFixedSize(true);
    listView.setAdapter(new SportAdapter(this));
    listView.setClickListener(this);
}

如此示例中所示https://gist.github.com/PomepuyN/c30760eaee1e58fdd8fa

啊...

当我从BoxInsetLayout将磨损布局更改为WatchViewStub时，WearableListView始终为null

1 个答案: