无法在我的活动中显示微调器

Question

我的儿童活动中有一个旋转器。这意味着我的活动是活动组的子活动，

当我单击微调器时，它崩溃了。在我单击选项之前它崩溃了（它甚至没有显示选项）请参阅此处：

public class PriceCalculator extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.calculator);

        Spinner metalSpinner=(Spinner)findViewById(R.id.metalSpinner);
        ArrayAdapter<String> metalDataAdapter=new ArrayAdapter<String>(getApplicationContext(), android.R.layout.simple_spinner_item,getResources().getStringArray(R.array.Metals));

        metalSpinner.setAdapter(metalDataAdapter);

        metalSpinner.setOnItemSelectedListener(new OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                TextView priceTextView=(TextView)findViewById(R.id.priceTextView);
                priceTextView.setText(""+parent.getItemAtPosition(position));
            }
            @Override
            public void onNothingSelected(AdapterView<?> arg0) {}
        });
    }

}

我的错误日志此处：

10-18 17:25:24.828: ERROR/AndroidRuntime(32670): FATAL EXCEPTION: main
10-18 17:25:24.828: ERROR/AndroidRuntime(32670): android.view.WindowManager$BadTokenException: Unable to add window -- token android.app.LocalActivityManager$LocalActivityRecord@44eed660 is not valid; is your activity running?
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.view.ViewRoot.setView(ViewRoot.java:505)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.view.Window$LocalWindowManager.addView(Window.java:424)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.app.Dialog.show(Dialog.java:241)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.app.AlertDialog$Builder.show(AlertDialog.java:802)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.widget.Spinner.performClick(Spinner.java:257)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.view.View$PerformClick.run(View.java:8816)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.os.Handler.handleCallback(Handler.java:587)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.os.Handler.dispatchMessage(Handler.java:92)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.os.Looper.loop(Looper.java:123)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at android.app.ActivityThread.main(ActivityThread.java:4627)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at java.lang.reflect.Method.invokeNative(Native Method)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at java.lang.reflect.Method.invoke(Method.java:521)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-18 17:25:24.828: ERROR/AndroidRuntime(32670):     at dalvik.system.NativeStart.main(Native Method)

您的活动正在运行吗？ 但我的活动正在运行。难道是孩子的活动发生了？

Answer 1

尝试替换，

setContentView(R.layout.calculator);

通过

View contentView = LayoutInflater.from(getParent()).inflate(R.layout.calculator, null);
setContentView(contentView);

Answer 2

尝试将适配器的Context更改为当前的活动上下文。该行：

ArrayAdapter<String> metalDataAdapter=new ArrayAdapter<String>(getApplicationContext(), android.R.layout.simple_spinner_item,getResources().getStringArray(R.array.Metals));

应该更改为：

ArrayAdapter<String> metalDataAdapter=new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,getResources().getStringArray(R.array.Metals));

AFAIK 在创建所有 UI 组件时最好使用当前的 Activity 上下文