java - Android Studio : Try-catch exception crashes application

Question

我正在测试代码内部的一些漏洞，并尝试通过在用户输入无效时抛出异常来修复它们。现在，当我实现 try-catch 并在手机上运行该应用程序时，当我输入无效输入时，它会崩溃。

我假设我的代码没有捕获 addData 方法的异常。是否有其他方法来实现异常，或者如何才能从 addData 方法捕获异常？

package com.odisee.photoboothapp;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.EditText;
import android.widget.Toast;

import com.odisee.photoboothapp.fontchanger.FontChangeTextView;

public class Form_Database extends AppCompatActivity {
DatabaseHelper myDb;

int selectedId;
RadioGroup test;
RadioButton editEducation;
EditText editName, editSurname, editEmail;
Button btnAddData;

@Override
protected void onCreate(Bundle savedInstanceState) throws IllegalArgumentException {
    super.onCreate(savedInstanceState);
    getSupportActionBar().hide();
    setContentView(R.layout.activity_form__database);

    myDb = new DatabaseHelper(this);

    test = (RadioGroup)findViewById(R.id.radioButtonChoice);

    editName = (EditText)findViewById(R.id.edit_Name);
    editSurname = (EditText)findViewById(R.id.edit_Surname);
    editEmail = (EditText)findViewById(R.id.edit_Email);


    btnAddData = (Button)findViewById(R.id.btnSend);
    try {
        addData();
    }
    catch(IllegalArgumentException e) {
        Toast.makeText(Form_Database.this,"Data not inserted" + e.getMessage(),Toast.LENGTH_LONG).show();
    }
}

public void addData() {
    btnAddData.setOnClickListener(
            new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                        if(editName.getText().toString().contains("DROP")) {
                            throw new IllegalArgumentException("SQL Exceptie!");
                        }
                        else {

                            selectedId = test.getCheckedRadioButtonId();
                            editEducation = (RadioButton)findViewById(selectedId);
                            boolean isInserted = myDb.insertData(editName.getText().toString(), editSurname.getText().toString(), editEmail.getText().toString(), editEducation.getText().toString());

                            sendEmail();

                            if(isInserted == true) {
                                Toast.makeText(Form_Database.this,"Data inserted",Toast.LENGTH_LONG).show();
                            }
                            else {
                                Toast.makeText(Form_Database.this,"Data not inserted",Toast.LENGTH_LONG).show();
                            }
                        }
                }
            }
    );
}

public void sendEmail() {
    //Getting content for email
    String email = editEmail.getText().toString();
    String subject = "testberichtje voor lorenzo";
    String message = "testberichtje voor lorenzo";

    //Creating SendMail object
    SendMail sm = new SendMail(this, email, subject, message);

    //Executing sendmail to send email
    sm.execute();
}

}

05-01 17:58:17.021 30232-30232/com.odisee.photoboothapp E/AndroidRuntime: FATAL EXCEPTION: main Process: com.odisee.photoboothapp, PID: 30232 java.lang.IllegalArgumentException: SQL Exceptie! at com.odisee.photoboothapp.Form_Database$1.onClick(Form_Database.java:55) at android.view.View.performClick(View.java:5697) at android.widget.TextView.performClick(TextView.java:10826) at android.view.View$PerformClick.run(View.java:22526) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:158) at android.app.ActivityThread.main(ActivityThread.java:7224) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)

Answer 1

尝试使 catch 更通用，以便您可以实际捕获错误，然后打印堆栈跟踪以便您可以看到问题:

try{
    //Try to do something on here
}catch(Exception error1) {
    Log.e(TAG, "The exception caught while executing the process. (error1)")
    error1.printStackTrace();
}