android - 具有自定义样式的 TextView 导致奇怪的膨胀异常

Question

我正在开发一个 Android 项目，并且正在创建一个自定义 ListView 。 ListView 包含多个 TextView ，我正在为我的 TextView 创建一个样式，因此我不必一遍又一遍地重复相同的样式。

下面是我的布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <TextView android:id="@+id/txtFirstOccurred"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        style="@style/CrashGroup"/>

    <TextView android:id="@+id/txtLastOccurred"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        style="@style/CrashGroup"/>
</LinearLayout>

下面是我的 TextView 的样式

<style name="CrashGroup">
        <item name="android:singleLine">false</item>
        <item name="android:textSize">@android:style/TextAppearance.Small</item>
        <item name="android:gravity">center_vertical</item>
    </style>

下面是我如何扩展 XML 以显示在 ListView 上。

@Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        try
        {
            convertView = LayoutInflater.from(getContext()).inflate(R.layout.android_crash_group_layout, null);

            TextView txtFirstOccurred = (TextView)convertView.findViewById(R.id.txtFirstOccurred);
            txtFirstOccurred.setText(getItem(position).getFirstOccurred());

            TextView txtLastOccurred = (TextView)convertView.findViewById(R.id.txtLastOccurred);
            txtLastOccurred.setText(getItem(position).getLastOccurred());


            return convertView;
        }
        catch (Exception ex)
        {
            Log.e(TAG, ex.toString());
            return null;
        }
    }

我收到的错误是:

Process: com.BoardiesITSolutions.CritiMonApp, PID: 1451 java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference at android.widget.AbsListView.obtainView(AbsListView.java:2360) at android.widget.ListView.makeAndAddView(ListView.java:1864) at android.widget.ListView.fillDown(ListView.java:698) at android.widget.ListView.fillFromTop(ListView.java:759) at android.widget.ListView.layoutChildren(ListView.java:1673) at android.widget.AbsListView.onLayout(AbsListView.java:2148) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.support.v4.widget.DrawerLayout.onLayout(DrawerLayout.java:890) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2072) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1829) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5779) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767) at android.view.Choreographer.doCallbacks(Choreographer.java:580) at android.view.Choreographer.doFrame(Choreographer.java:550) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)

这似乎与样式有关，就好像我从 TextView 中删除此样式属性一样，它似乎工作正常。

Answer 1

我认为您返回的convertView有时是null，因为处理convertView很棘手。

确保您有一个值。你可以使用类似的东西:

 @Override
  public View getView(int position, View convertView, ViewGroup parent) {
    LayoutInflater inflater = (LayoutInflater) context
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    TextView text = null;

    if (convertView == null) {
      convertView = inflater.inflate(R.layout.listrow_details, null);
    }

    text = (TextView) convertView.findViewById(R.id.textView1);
    text.setText(children);

    return convertView;
  }

希望有帮助。