java - 在 ListView 中使用 Intent 时发生 fatal error

Question

我正在尝试根据我在 ListView 中选择的项目来打开一个 Activity 。

将点击添加到我的ListView:

private void addClickList() {
        myList.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                Intent intent = new Intent(FirstActi.this, SecondActi.class);
                startActivity(intent);
            }

        });
}

这是我针对这两项 Activity 的 android list :

        <activity
            android:name=".FirstActi"
            android:label="@string/firstActi">
            <intent-filter>
                <action android:name="com.example.applicationname.FirstActi" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter> 
        </activity>

        <activity
            android:name=".SecondActi"
            android:label="@string/secondActi" >
        </activity>

这是 logcat 的输出:

05-20 17:28:58.251: E/AndroidRuntime(27073): FATAL EXCEPTION: main
05-20 17:28:58.251: E/AndroidRuntime(27073): Process: com.example.applicationname, PID: 27073
05-20 17:28:58.251: E/AndroidRuntime(27073): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.applicationname/com.example.applicationname.FirstActi}: java.lang.InstantiationException: can't instantiate class com.example.arduinodivecompanion.SecondActi; no empty constructor
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2121)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.ActivityThread.access$800(ActivityThread.java:135)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.os.Handler.dispatchMessage(Handler.java:102)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.os.Looper.loop(Looper.java:136)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.ActivityThread.main(ActivityThread.java:5017)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at java.lang.reflect.Method.invokeNative(Native Method)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at java.lang.reflect.Method.invoke(Method.java:515)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at dalvik.system.NativeStart.main(Native Method)
05-20 17:28:58.251: E/AndroidRuntime(27073): Caused by: java.lang.InstantiationException: can't instantiate class com.example.applicationname.SecondActi; no empty constructor
05-20 17:28:58.251: E/AndroidRuntime(27073):    at java.lang.Class.newInstanceImpl(Native Method)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at java.lang.Class.newInstance(Class.java:1208)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.Instrumentation.newActivity(Instrumentation.java:1061)
05-20 17:28:58.251: E/AndroidRuntime(27073):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2112)
05-20 17:28:58.251: E/AndroidRuntime(27073):    ... 11 more

我认为这可能是 Intent 过滤器的问题

Answer 1

根据 Android 指南，您不应在 Activity 类中创建构造函数，因为 Android 操作系统创建 Activity 类的对象，并使用该类的默认空构造函数来创建对象。您不应该直接创建 Activity 对象。

看起来您已经在 Activity 中创建了构造函数。从您的 Activity 中删除构造函数并使用生命周期回调。