2

我有一个扩展 LinearLayout 的自定义视图，具有以下构造函数：

public class CustomView extends LinearLayout {

public CustomView(Context context) {
    this(context, null);
}

public CustomView(Context context, AttributeSet attrs) {
    this(context, attrs, R.attr.customViewStyle);
}

public CustomView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    /* set custom attributes with TypedArray */
}

    /* other methods */
}

在我的 /res/values/attrs.xml 中：

<attr name="customViewStyle" format="reference" />

<declare-styleable name="CustomeView">
    <attr name="value" format="integer" />
    <attr name="android:imeOptions" />
    <attr name="android:imeActionId" />
    <attr name="android:imeActionLabel" />
</declare-styleable>

在我的 /res/values/styles.xml 中：

<style name="AppTheme" parent="@android:style/Theme.Black">
    <item name="android:windowBackground">@drawable/bg_dark_fiber</item>
    <item name="customViewStyle">@style/CustomViewStyle</item>
</style>

<style name="CustomViewStyle">
    <item name="android:clickable">true</item>
    <item name="android:focusable">true</item>
    <item name="android:focusableInTouchMode">true</item>
</style>

AppTheme 设置为整个应用程序的主题。期望的结果是我的自定义视图默认是可聚焦和可点击的，而无需在我的布局文件中添加这些属性（而常规的 LinearLayout 不是）。当我运行该应用程序时，它会因以下堆栈跟踪而崩溃：

05-17 14:58:53.010: E/ActivityThread(26767): Failed to inflate
05-17 14:58:53.010: E/ActivityThread(26767): android.view.InflateException: Binary XML file line #8: Error inflating class com.example.customviews.CustomView
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.createView(LayoutInflater.java:518)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:570)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.rInflate(LayoutInflater.java:623)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
05-17 14:58:53.010: E/ActivityThread(26767):    at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:212)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.Activity.setContentView(Activity.java:1657)
05-17 14:58:53.010: E/ActivityThread(26767):    at com.example.pincode.PinCodeActivity.onCreate(PinCodeActivity.java:26)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.ActivityThread.access$1500(ActivityThread.java:123)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.os.Handler.dispatchMessage(Handler.java:99)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.os.Looper.loop(Looper.java:130)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.app.ActivityThread.main(ActivityThread.java:3835)
05-17 14:58:53.010: E/ActivityThread(26767):    at java.lang.reflect.Method.invokeNative(Native Method)
05-17 14:58:53.010: E/ActivityThread(26767):    at java.lang.reflect.Method.invoke(Method.java:507)
05-17 14:58:53.010: E/ActivityThread(26767):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
05-17 14:58:53.010: E/ActivityThread(26767):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
05-17 14:58:53.010: E/ActivityThread(26767):    at dalvik.system.NativeStart.main(Native Method)
05-17 14:58:53.010: E/ActivityThread(26767): Caused by: java.lang.reflect.InvocationTargetException
05-17 14:58:53.010: E/ActivityThread(26767):    at java.lang.reflect.Constructor.constructNative(Native Method)
05-17 14:58:53.010: E/ActivityThread(26767):    at java.lang.reflect.Constructor.newInstance(Constructor.java:415)
05-17 14:58:53.010: E/ActivityThread(26767):    at android.view.LayoutInflater.createView(LayoutInflater.java:505)
05-17 14:58:53.010: E/ActivityThread(26767):    ... 21 more
05-17 14:58:53.010: E/ActivityThread(26767): Caused by: java.lang.NoSuchMethodError: android.widget.LinearLayout.<init>
05-17 14:58:53.010: E/ActivityThread(26767):    at com.example.customviews.CustomView.<init>(CustomView.java:98)
05-17 14:58:53.010: E/ActivityThread(26767):    at com.example.customviews.CustomView.<init>(CustomView.java:94)
05-17 14:58:53.010: E/ActivityThread(26767):    ... 24 more

我不明白是什么导致了 InflateException 的调用super(context, attrs, defStyle)。我也尝试过super(context, attrs, 0)，但这并没有帮助，这真的很奇怪，因为即使是 LinearLayout 也使用它，就像我检查过源代码的大多数其他视图一样。

4

3 回答 3

13

I found this answer on the Android Developers Google Group:

The three-argument version of LinearLayout constructor is only available with API 11 and higher -- i.e. Android 3.0.

This dependency has to be satisfied at runtime by the actual Android version running on the device.

I was testing on a handset running Gingerbread (2.3.3). Sure enough, when I ran the program on an emulator with ICS (4.0.3), it worked fine. Still hunting for a workaround so I can use my code on pre-Honeycomb.

于 2012-05-22T17:40:32.837 回答
0

您的构造函数正在调用this而不是super. 如果你改变它，那么它将起作用。

我刚刚用构造函数扩展了线性布局来测试它是否有效。

于 2012-05-17T22:52:35.773 回答
0

我在自定义 LinearLayout 时也遇到了这个问题。我所做的是调用super而不是this在构造函数中，并在单独的方法中设置属性。

public class CustomView extends LinearLayout {

public CustomView(Context context) {
    super(context);
}

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

public CustomView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    setAttributes(attrs);
}

private void setAttributes(AttributeSet attrs) {
    /* set custom attributes with TypedArray */
}
    /* other methods */
}
于 2014-06-04T10:50:02.453 回答