Question

这是我被卡住的片段。我想要识别layout_root

fragment_new_weather.xml的片段

<ScrollView 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="fill_parent"
    android:layout_height="fill_parent">
    <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="wrap_content"
        android:paddingBottom="@dimen/activity_vertical_margin"
        android:paddingStart="@dimen/activity_horizontal_margin"
        android:paddingEnd="@dimen/activity_horizontal_margin"
        android:paddingTop="@dimen/activity_vertical_margin"
        tools:context="com.a5corp.weather.WeatherActivity$PlaceholderFragment">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:id="@+id/city_field"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:textColor="#FFFFFF"
            android:ellipsize="end"
            android:maxLines="1"
            android:textSize="48sp" />

        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:weightSum="1"
            android:id="@+id/linearLayout2"
            android:layout_below="@+id/daily_view"
            android:layout_alignParentStart="true"
            android:layout_alignParentLeft="true">

                <TextView
                    android:layout_width="wrap_content"
                    android:id="@+id/temp_text_view"
                    android:layout_height="wrap_content" />

                <LinearLayout
                    android:orientation="horizontal"
                    android:id="@+id/layout_root"
                    android:layout_width="wrap_content"
                    android:layout_height="match_parent" >

                    <TextView
                        android:layout_width="wrap_content"
                        android:id="@+id/temp_text_view1"
                        android:layout_height="wrap_content" />

                    <LinearLayout
                        android:orientation="vertical"
                        android:layout_width="wrap_content"
                        android:layout_height="match_parent"
                        android:paddingStart="5dp"
                        android:minWidth="85sp"
                        android:paddingEnd="2dp"
                        android:layout_marginEnd="8dp"
                        android:paddingLeft="5dp"
                        android:paddingRight="2dp"
                        android:layout_marginRight="8dp">

                        <TextView
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:textAppearance="?android:attr/textAppearanceLarge"
                            android:id="@+id/weather_icon1"
                            android:textSize="70sp"
                            android:textColor="#FFFFFF"
                            android:layout_gravity="center" />

                        <TextView
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:textAppearance="?android:attr/textAppearanceMedium"
                            android:id="@+id/details_view1"
                            android:textColor="#FFFFFF" />
                    </LinearLayout>
                </LinearLayout>
        </LinearLayout>
 <!-- Code below this in the file works properly-->

这是我的片段的onCreateView我坚持：

public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    //Working Code above
    layout = (LinearLayout) getActivity().findViewById(R.id.layout_root);
    if (layout == null)
        Log.e("NewFragment" , "Layout is null");
    if (rootView.findViewById(R.id.temp_text_view) == null)
        Log.e("NewFragment" , "Temp Text Is Null");
    if (rootView.findViewById(R.id.temp_text_view1) == null)
        Log.e("NewFragment" , "Temp Text 1 Is Null");
    //Working code below
}

问题是布局总是返回null，而temp_text_view（layout_root外部）和temp_text_view1（layout_root内部）都不返回 null，而layout_root总是返回null。

以下是我正在尝试实施的代码：

for (int i = 0; i < 10; ++i) {
        LinearLayout child = new LinearLayout(getContext());
        child.setOrientation(LinearLayout.VERTICAL);
        child.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT , ViewGroup.LayoutParams.MATCH_PARENT));
        child.setPadding(5 , 0 , 2 , 0);
        child.setPaddingRelative(5 , 0 , 2 , 0);

        TextView wIcon = new TextView(getContext());
        TextView detField = new TextView(getContext());

        wIcon.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT , ViewGroup.LayoutParams.WRAP_CONTENT));
        wIcon.setTextSize(70);
        wIcon.setTextColor(Color.WHITE);
        wIcon.setTextAppearance(getContext() , android.R.style.TextAppearance_Large);
        wIcon.setGravity(Gravity.CENTER);

        detField.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT , ViewGroup.LayoutParams.WRAP_CONTENT));
        detField.setTextAppearance(getContext() , android.R.style.TextAppearance_Medium);
        detField.setTextColor(Color.WHITE);

        wIcon = weatherIcon[i];
        detField = detailsField[i];
        layout.addView(wIcon);
        layout.addView(detField);
    }

Answer 1

更改，

layout = (LinearLayout) getActivity().findViewById(R.id.layout_root);

要，

layout = (LinearLayout) rootView.findViewById(R.id.layout_root);

当您尝试访问getActivity()中的某个元素时，请使用Activity。当您尝试访问当前布局中的某些内容时使用rootView，在本例中为fragment_new_weather.xml。

另一个linearlayout内的LinearLayout始终返回null

1 个答案: