java - 运行方法时出现很多错误

Question

好的，我已经开始在 Eclipse 中使用 Java 进行编程，并制作一个 Android 应用程序。在我的一项 Activity 中，我保存了人们的详细信息 - 姓名和手机号码(以便稍后向他们发送短信)。然而，当执行该方法时，会引发大量错误。该方法如下所示，通过单击按钮(标准内容)来执行:

它还触发另一种方法，写入文件:

public void addpeople_action_save(View view) {
    EditText et_addpeople_name = (EditText) findViewById(R.id.addpeople_name);
    EditText et_addpeople_number = (EditText) findViewById(R.id.addpeople_number);
    String person_name = et_addpeople_name.getText().toString();///parses from the EditText to a string.
    String person_number = et_addpeople_number.getText().toString();

    ///Next section is writing the two strings to a internal file, as a CSV format.
    ///eg: Bill, 0123567898
    ///this will actually append the string to an arraylist of strings, before writing it back to the file.
    ArrayList<PeopleDetails> peopledetails_return =Readpeopledetails();///creates an arraylist containing people's details
    ///read from file
    PeopleDetails person_details = new PeopleDetails("", ""); 
    person_details.name = person_name;
    person_details.number = person_number;
    peopledetails_return.add(person_details);
    peopledetails_return = sortList(peopledetails_return);
    peopledetails_write(peopledetails_return);

    /
    ///or will write a new file if it doesn't exist.
    ///New method(PeopleNumber, PeopleName, Filename)
    ///will write to file.
}

以及错误:

01-02 08:47:20.290: E/AndroidRuntime(1966): FATAL EXCEPTION: main
01-02 08:47:20.290: E/AndroidRuntime(1966): java.lang.IllegalStateException: Could not execute method of the activity
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.view.View$1.onClick(View.java:3633)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.view.View.performClick(View.java:4240)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.view.View$PerformClick.run(View.java:17721)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.os.Handler.handleCallback(Handler.java:730)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.os.Handler.dispatchMessage(Handler.java:92)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.os.Looper.loop(Looper.java:137)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.app.ActivityThread.main(ActivityThread.java:5103)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at java.lang.reflect.Method.invokeNative(Native Method)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at java.lang.reflect.Method.invoke(Method.java:525)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at dalvik.system.NativeStart.main(Native Method)
01-02 08:47:20.290: E/AndroidRuntime(1966): Caused by: java.lang.reflect.InvocationTargetException
01-02 08:47:20.290: E/AndroidRuntime(1966):     at java.lang.reflect.Method.invokeNative(Native Method)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at java.lang.reflect.Method.invoke(Method.java:525)
01-02 08:47:20.290: E/AndroidRuntime(1966):     at android.view.View$1.onClick(View.java:3628)
01-02 08:47:20.290: E/AndroidRuntime(1966):     ... 11 more
01-02 08:47:20.290: E/AndroidRuntime(1966): Caused by: java.lang.NullPointerException
01-02 08:47:20.290: E/AndroidRuntime(1966):     at com.example.partyorganiser.AddPeople.addpeople_action_save(AddPeople.java:63)
01-02 08:47:20.290: E/AndroidRuntime(1966):     ... 14 more

感谢您的帮助；)

编辑:阅读器方法代码:

public ArrayList<PeopleDetails> Readpeopledetails(){        String filereadfrom = "";





            try{            InputStream filestream = openFileInput("PeopleDetailsFile");            if (filestream != null){///first time file is not created. Later will be created, when writing back to the file.
            InputStreamReader inputStreamReader = new InputStreamReader(filestream);
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String receiveString = "";
            StringBuilder stringBuilder = new StringBuilder();

            while ( (receiveString = bufferedReader.readLine()) != null ) {
                stringBuilder.append(receiveString);

            }
            filereadfrom = stringBuilder.toString();
            ///using two delimiters: ";" and ","
            ///split based on ";" to get people as a string, put in array
            ///then split all strings in that array, based on "," and place each into the array peopledetails
            String[] parsearray = filereadfrom.split(";");
            ArrayList<PeopleDetails> peopledetails_array = new ArrayList<PeopleDetails>();

                for(String personstring: parsearray){
                    String[] split = personstring.split(",");
                    PeopleDetails peopledetails_unit = new PeopleDetails("", "");
                    peopledetails_unit.name= split[0];
                    peopledetails_unit.number = split[1];
                    peopledetails_array.add(peopledetails_unit);

                      ///neatly initializes and writes to the peopledetails_array in one section. 
            }
                filestream.close();
                inputStreamReader.close();



            return peopledetails_array; }       }




                    catch(FileNotFoundException e) {
            Log.e("File not found" , e.toString());
            }
                        catch(IOException e){
            Log.e("Can't read file" , e.toString());





                }       return null;

Answer 1

此位置出现 NullPointerException:

com.example.partyorganiser.AddPeople.addpeople_action_save(AddPeople.java:63)

很难说更多