Java 无法启动活动组件信息问题
我想在单击按钮时打开另一个活动。我看不出问题出在哪里。。我希望这里有人能告诉我出了什么问题 从活动一单击一次:Java 无法启动活动组件信息问题,java,android,android-activity,Java,Android,Android Activity,我想在单击按钮时打开另一个活动。我看不出问题出在哪里。。我希望这里有人能告诉我出了什么问题 从活动一单击一次: public void onClick(View v) { // TODO Auto-generated method stub switch (v.getId()) { case R.id.bBerakna: if (isEditTextEmpty(anslag_mm) | isEditTextEmpty(bladVikten)
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.bBerakna:
if (isEditTextEmpty(anslag_mm) | isEditTextEmpty(bladVikten)
| isEditTextEmpty(jamnViktsLage)
| isEditTextEmpty(rotorSpann) | isEditTextEmpty(varv_Minut)) {
Toast t = Toast.makeText(this,
"Du måste fylla i alla parametrarna!",
Toast.LENGTH_SHORT);
t.show();
break;
} else {
Intent resultat = new Intent(Input.this,
ExpandableListViewAppActivity.class);
resultat.putExtra("ROTOR", rotorSp);
resultat.putExtra("RPM", rpm);
resultat.putExtra("JVIKT", jämVikL);
resultat.putExtra("BVIKT", bladVikt);
resultat.putExtra("ANSLAG", anslFäLä);
startActivity(resultat);
}
};
这是应该打开的活动二的创建:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent getIntent = getIntent();
rotorSp = (double) getIntent.getDoubleExtra("ROTOR", 0);
rpm = (double) getIntent.getDoubleExtra("RPM", 0);
jämVikL = (double) getIntent.getDoubleExtra("JVIKT", 0);
bladVikt = (double) getIntent.getDoubleExtra("BVIKT", 0);
anslFäLä = (double) getIntent.getDoubleExtra("ANSLAG", 0);
berakna();
// Döljer tangentbordet
InputMethodManager inputManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
inputManager.hideSoftInputFromWindow(
getCurrentFocus().getWindowToken(),
InputMethodManager.HIDE_NOT_ALWAYS);
setContentView(R.layout.main);
}
这是来自LogCat的:
01-20 19:09:09.068: E/AndroidRuntime(722): FATAL EXCEPTION: main
01-20 19:09:09.068: E/AndroidRuntime(722): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.rotorbladen.tobias/com.rotorbladen.tobias.ExpandableListViewAppActivity}: java.lang.NullPointerException
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.os.Handler.dispatchMessage(Handler.java:99)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.os.Looper.loop(Looper.java:123)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.ActivityThread.main(ActivityThread.java:4627)
01-20 19:09:09.068: E/AndroidRuntime(722): at java.lang.reflect.Method.invokeNative(Native Method)
01-20 19:09:09.068: E/AndroidRuntime(722): at java.lang.reflect.Method.invoke(Method.java:521)
01-20 19:09:09.068: E/AndroidRuntime(722): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
01-20 19:09:09.068: E/AndroidRuntime(722): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
01-20 19:09:09.068: E/AndroidRuntime(722): at dalvik.system.NativeStart.main(Native Method)
01-20 19:09:09.068: E/AndroidRuntime(722): Caused by: java.lang.NullPointerException
01-20 19:09:09.068: E/AndroidRuntime(722): at com.rotorbladen.tobias.ExpandableListViewAppActivity.onCreate(ExpandableListViewAppActivity.java:92)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-20 19:09:09.068: E/AndroidRuntime(722): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
01-20 19:09:09.068: E/AndroidRuntime(722): ... 11 more
可扩展列表视图活动的第92行是什么?另外,
getDoubleExtra()
返回一个原语double。不需要演员阵容。发布berakna()代码>方法这是ExpandableListViewAppActivity:getCurrentFocus().getWindowToken()的第92行,如上面的活动二源代码所示。berakna只是我知道可以工作的计算,我可以在调试器中看到结果。