handleMessage sendMessage发送long型obj出错，cannot be cast to java.lang.Lang

这个错误通常是因为你在使用 `sendMessage()` 方法时传递了一个 `long` 类型的参数。而 `sendMessage()` 方法的参数必须是一个 `Message` 对象或者是一个实现了 `Parcelable` 接口的对象。

为了解决这个问题，你可以将 `long` 类型的参数封装成一个 `Message` 对象，然后再传递给 `sendMessage()` 方法。例如：

long myLongValue = 123456789L;
Message message = Message.obtain();
message.obj = myLongValue;
handler.sendMessage(message);

这样就可以避免出现类型转换错误了。

相关问题

这是什么问题FATAL EXCEPTION: main Process: com.example.lightcontrol_app2, PID: 4533 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.lightcontrol_app2/com.example.lightcontrol_app2.ui.control.activity.EditingSingleLampActivity}: java.lang.RuntimeException: setOnItemClickListener cannot be used with a spinner. at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2668) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2729) at android.app.ActivityThread.-wrap12(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1480) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6176) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:893) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:783) Caused by: java.lang.RuntimeException: setOnItemClickListener cannot be used with a spinner. at android.widget.Spinner.setOnItemClickListener(Spinner.java:571) at com.example.lightcontrol_app2.ui.control.activity.EditingSingleLampActivity.init(EditingSingleLampActivity.java:111) at com.example.lightcontrol_app2.ui.control.activity.EditingSingleLampActivity.onCreate(EditingSingleLampActivity.java:65) at android.app.Activity.performCreate(Activity.java:6692) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2621) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2729) at android.app.ActivityThread.-wrap12(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1480) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6176) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:893) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:783)

这个错误是由于你在 Spinner 上使用了 `setOnItemClickListener` 方法，而这个方法不能用于 Spinner。Spinner 是一个下拉列表，你应该使用 `setOnItemSelectedListener` 方法来监听 Spinner 中选择的项目。请检查你的代码中是否有类似以下的代码：

spinner.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        // do something
    }
});

将其替换为以下代码：

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        // do something
    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
        // do something
    }
});

这样应该可以解决你遇到的问题。

java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=2, result=-1, data=Intent { act=inline-data (has extras) }} to activity {com.example.camerax_final/com.example.camerax_final.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.net.Uri.toString()' on a null object reference at android.app.ActivityThread.deliverResults(ActivityThread.java:4845) at android.app.ActivityThread.handleSendResult(ActivityThread.java:4886) at android.app.servertransaction.ActivityResultItem.execute(ActivityResultItem.java:51) at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:214) at android.app.ActivityThread.main(ActivityThread.java:7356) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.net.Uri.toString()' on a null object reference at com.example.camerax_final.MainActivity.onActivityResult(MainActivity.java:87) at android.app.Activity.dispatchActivityResult(Activity.java:8110) at android.app.ActivityThread.deliverResults(ActivityThread.java:4838) at android.app.ActivityThread.handleSendResult(ActivityThread.java:4886) at android.app.servertransaction.ActivityResultItem.execute(ActivityResultItem.java:51) at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:214) at android.app.ActivityThread.main(ActivityThread.java:7356) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

这个错误信息是由于在 onActivityResult() 方法中，尝试调用一个 null 对象的方法导致的 NullPointerException。具体来说，是在该方法的第 87 行尝试调用了一个 null 对象的 toString() 方法，而这个对象是一个 Uri 对象。因此，你需要先检查 onActivityResult() 方法中获取的 Intent 是否包含有效的 Uri 数据，如果 Uri 为 null，则需要避免调用 toString() 方法。