我见过很多类似的问题,但我想不出什么我做错了。我做了一个非常简单的应用程序来复制错误。安卓:IllegalStateException异常:活动遭到破坏的计算器
该应用程序执行以下操作:
它在MainActivty的onCreate中添加一个片段。
用户可以从对话框添加另一个片段。
当对话框要求在MainActivity的addFragment方法抛出一个异常的事务执行。
这里是在MainActivity
package com.example.testapp;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.view.View;
import android.widget.Button;
public class MainActivity extends FragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button button = (Button) findViewById(R.id.add_button);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
AddButtonDialog addButtonDialog = new AddButtonDialog();
addButtonDialog.show(getSupportFragmentManager(), "ADD");
}
});
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
CustomFragment fragment = new CustomFragment();
transaction.add(R.id.fragment_container, fragment);
transaction.commit();
}
public void addButton() {
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
CustomFragment fragment = new CustomFragment();
transaction.add(R.id.fragment_container, fragment);
transaction.commit(); // <-- Exception
}
}
这里是调用在MainActivity
public class AddButtonDialog extends DialogFragment {
public Dialog onCreateDialog(Bundle savedInstanceState) {
final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
final LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.new_button_dialog, null);
builder.setView(view)
.setPositiveButton("Add", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int id) {
MainActivity main = new MainActivity();
main.addButton();
}
});
return builder.create();
}
}
的AddButtonDialog这里是堆栈跟踪
02-14 10:09:27.781: E/AndroidRuntime(26291): FATAL EXCEPTION: main
02-14 10:09:27.781: E/AndroidRuntime(26291): java.lang.IllegalStateException: Activity has been destroyed
02-14 10:09:27.781: E/AndroidRuntime(26291): at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1365)
02-14 10:09:27.781: E/AndroidRuntime(26291): at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
02-14 10:09:27.781: E/AndroidRuntime(26291): at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574)
02-14 10:09:27.781: E/AndroidRuntime(26291): at com.example.testapp.MainActivity.addButton(MainActivity.java:35)
02-14 10:09:27.781: E/AndroidRuntime(26291): at com.example.testapp.AddButtonDialog$1.onClick(AddButtonDialog.java:22)
02-14 10:09:27.781: E/AndroidRuntime(26291): at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:185)
02-14 10:09:27.781: E/AndroidRuntime(26291): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 10:09:27.781: E/AndroidRuntime(26291): at android.os.Looper.loop(Looper.java:137)
02-14 10:09:27.781: E/AndroidRuntime(26291): at android.app.ActivityThread.main(ActivityThread.java:5328)
02-14 10:09:27.781: E/AndroidRuntime(26291): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 10:09:27.781: E/AndroidRuntime(26291): at java.lang.reflect.Method.invoke(Method.java:511)
02-14 10:09:27.781: E/AndroidRuntime(26291): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
02-14 10:09:27.781: E/AndroidRuntime(26291): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
02-14 10:09:27.781: E/AndroidRuntime(26291): at dalvik.system.NativeStart.main(Native Method)
我相当肯定我不是掌握片段生命周期的概念。请有人这么好解释我做错了什么。
'MainActivity main = new MainActivity();'不这样做。你不应该尝试实例化活动 –
谢谢。在我的主要活动中调用方法的正确方法是什么? – Fuzz
尝试'MainActivity.this.add()' –