Question

我制作了一个简单的应用程序，需要两个数字并添加它们但是在按钮上单击我的应用程序每次都会崩溃。我是android的新手，如果有人可以帮助我，我真的很感激

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.ornadmin.myapplication.MainActivity">

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="number"
        android:ems="10"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true"
        android:layout_marginStart="21dp"
        android:layout_marginTop="29dp"
        android:id="@+id/editText"
        android:hint="number 1" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="number"
        android:ems="10"
        android:layout_below="@+id/editText"
        android:layout_alignEnd="@+id/editText"
        android:layout_marginTop="32dp"
        android:id="@+id/editText2"
        android:hint="number 2" />

    <TextView
        android:text="Result"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="13dp"
        android:id="@+id/textView"
        android:layout_below="@+id/editText2"
        android:layout_alignStart="@+id/editText2"
        android:layout_marginTop="57dp"
        android:textSize="30sp" />

    <Button
        android:text="sum"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/button"
        android:onClick="onButtonClick (MainActivity)"
        android:layout_alignTop="@+id/textView"
        android:layout_alignStart="@+id/textView"
        android:layout_marginTop="97dp" />
</RelativeLayout>

主要活动

package com.example.ornadmin.myapplication;

import android.app.Activity;
import android.app.IntentService;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

import com.google.android.gms.appindexing.Action;
import com.google.android.gms.appindexing.AppIndex;
import com.google.android.gms.appindexing.Thing;
import com.google.android.gms.common.api.GoogleApiClient;

public class MainActivity extends Activity {

    /**
     * ATTENTION: This was auto-generated to implement the App Indexing API.
     * See https://g.co/AppIndexing/AndroidStudio for more information.
     */
    private GoogleApiClient client;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
        client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
    }

    public void onButtonClick(View v) {
        EditText e1 = (EditText)findViewById(R.id.editText);
        EditText e2 = (EditText)findViewById(R.id.editText2);
        TextView t1 = (TextView)findViewById(R.id.textView);
        int num1 = Integer.parseInt(e1.getText().toString());
        int num2 = Integer.parseInt(e2.getText().toString());
        int sum = num1 + num2;
    }

    /**
     * ATTENTION: This was auto-generated to implement the App Indexing API.
     * See https://g.co/AppIndexing/AndroidStudio for more information.
     */
    public Action getIndexApiAction() {
        Thing object = new Thing.Builder()
                .setName("Main Page") // TODO: Define a title for the content shown.
                // TODO: Make sure this auto-generated URL is correct.
                .setUrl(Uri.parse("http://[ENTER-YOUR-URL-HERE]"))
                .build();
        return new Action.Builder(Action.TYPE_VIEW)
                .setObject(object)
                .setActionStatus(Action.STATUS_TYPE_COMPLETED)
                .build();
    }

    @Override
    public void onStart() {
        super.onStart();

        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
        client.connect();
        AppIndex.AppIndexApi.start(client, getIndexApiAction());
    }

    @Override
    public void onStop() {
        super.onStop();

        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
        AppIndex.AppIndexApi.end(client, getIndexApiAction());
        client.disconnect();
    }
}

LOG

 --------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
                  Process: com.example.ornadmin.myapplication, PID: 3812
                  java.lang.IllegalStateException: Could not find method onButtonClick (MainActivity)(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.widget.Button with id 'button'
                      at android.view.View$DeclaredOnClickListener.resolveMethod(View.java:4479)
                      at android.view.View$DeclaredOnClickListener.onClick(View.java:4443)
                      at android.view.View.performClick(View.java:5198)
                      at android.view.View$PerformClick.run(View.java:21147)
                      at android.os.Handler.handleCallback(Handler.java:739)
                      at android.os.Handler.dispatchMessage(Handler.java:95)
                      at android.os.Looper.loop(Looper.java:148)
                      at android.app.ActivityThread.main(ActivityThread.java:5417)
                      at java.lang.reflect.Method.invoke(Native Method)
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Application terminated.

Answer 1

问题出在这一行

android:onClick="onButtonClick (MainActivity)"

校正将是这样的

android:onClick="onButtonClick"

Android应用程序在按钮单击时崩溃

1 个答案: