Android TextView、setText 使用多个变量连接在一起

Question

我正在从数据库中提取数据，返回类实例中的值。在 Activity 的 onCreate 方法中，我设置内容视图，然后运行以下代码：

val thisObject:ClassCardJ = myDBAdapter.getAddressBookEntry(cardNum)
//val textFullName:String = (thisObject.getfName().toString() + " " + thisObject.getlName().toString())

val textFirstName:String = thisObject.getfName().toString()
val textLastName:String = thisObject.getlName().toString()
firstLine.setText(textFirstName)
Toast.makeText(AddressBookEntryActivity.this, thisObject.getlName().toString(), Toast.LENGTH_SHORT).show();

它将firstLine 文本设置为textFirstName 值，并使用我在textLastName 中使用的值显示一个toast。

但是，当我尝试将firstLine 的setText 更改为textFullName（取消注释后）时，我的程序强制关闭。我做错了什么有趣的事情吗？

根据请求，我的 logcat 堆栈跟踪（我尝试包含所有相关的内容并省略所有不相关的内容）：

I/ActivityManager(   67): Process com.android.email (pid 330) has died.
I/ActivityManager(   67): Starting: Intent { cmp=me.snapcard/.AddressBookActivity } from pid 393
I/ActivityManager(   67): Displayed me.snapcard/.AddressBookActivity: +589ms
I/ActivityManager(   67): Starting: Intent { cmp=me.snapcard/.AddressBookEntryActivity (has extras) } from pid 393
E/dalvikvm(  393): Could not find class 'scala.collection.mutable.StringBuilder', referenced from method me.snapcard.AddressBookEntryActivity.onCreate
W/dalvikvm(  393): VFY: unable to resolve new-instance 1148   (Lscala/collection/mutable/StringBuilder;) in Lme/snapcard/AddressBookEntryActivity;
D/dalvikvm(  393): VFY: replacing opcode 0x22 at 0x0050
D/dalvikvm(  393): VFY: dead code 0x0052-0091 in   Lme/snapcard/AddressBookEntryActivity;.onCreate (Landroid/os/Bundle;)V
D/AndroidRuntime(  393): Shutting down VM
W/dalvikvm(  393): threadid=1: thread exiting with uncaught exception (group=0x40015560)
E/AndroidRuntime(  393): FATAL EXCEPTION: main
E/AndroidRuntime(  393): java.lang.NoClassDefFoundError:   scala.collection.mutable.StringBuilder
E/AndroidRuntime(  393):    at   me.snapcard.AddressBookEntryActivity.onCreate(AddressBookEntryActivity.scala:40)
E/AndroidRuntime(  393):    at  android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
E/AndroidRuntime(  393):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
E/AndroidRuntime(  393):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
E/AndroidRuntime(  393):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
E/AndroidRuntime(  393):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
E/AndroidRuntime(  393):    at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(  393):    at android.os.Looper.loop(Looper.java:130)
E/AndroidRuntime(  393):    at android.app.ActivityThread.main(ActivityThread.java:3683)
E/AndroidRuntime(  393):    at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime(  393):    at java.lang.reflect.Method.invoke(Method.java:507)
E/AndroidRuntime(  393):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
E/AndroidRuntime(  393):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
E/AndroidRuntime(  393):    at dalvik.system.NativeStart.main(Native Method)
W/ActivityManager(   67):   Force finishing activity me.snapcard/.AddressBookEntryActivity
W/ActivityManager(   67):   Force finishing activity me.snapcard/.AddressBookActivity
W/ActivityManager(   67): Activity pause timeout for HistoryRecord{4082ce18 me.snapcard/.AddressBookEntryActivity}
I/dalvikvm(   67): Jit: resizing JitTable from 1024 to 2048
W/ActivityManager(   67): Launch timeout has expired, giving up wake lock!

Answer 1

就像你说的，你使用了 StringBuilder。我怀疑您的 scala.collection.mutable 对象的编码不允许其项目顺利串联。我强烈建议您将连接的字符串（仅包括 textFirstName 和 textLastName，如果您要单独使用它们）包装在 Scala StringBuilder 中。如果你想使用java.lang.StringBuilder，那么你可以通过简单地用java.lang.Stringbuilder包装Scala StringBuilder来转换Scala StringBuilder，详细信息此处。希望有帮助！