Question

我有“等待调试器附加”消息和一个空白活动，无论什么时候我都没有发生任何事情！我正在尝试做一个显示问题的简单主要活动，“+”是真的而“ - ”是假的。就像真假游戏一样。

这是我的manigest：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.calculator"
    android:versionCode="1"
    android:versionName="1.0" >
    <uses-permission android:name="android.permission.SET_DEBUG_APP"></uses-permission>


    <uses-sdk
        android:minSdkVersion="5"
        android:targetSdkVersion="18" />

    <application
        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme"
        android:debuggable="true"
        >

        <activity
            android:name="com.example.calculator.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

这是我的java：

package com.example.calculator;

import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

import android.widget.TextView;

public class MainActivity extends Activity implements android.view.View.OnClickListener {

    Button button;
    Button button2;
    Button button3; 
    TextView text;

    String[] questions ;
    boolean[] answers;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button = (Button) findViewById(R.id.button1);
        button2 = (Button) findViewById(R.id.button2);

        text = (TextView) findViewById(R.id.textView1) ;
        questions[0]="Are u hungry?";
        answers[0]=true;
        text.setText(questions[0]);




        button.setOnClickListener(this);
        button2.setOnClickListener(this);

    }
    public void onClick(View v) {
        //parsing should be here

          switch(v.getId()){

          case R.id.button1: 
              if( answers[0]==true){
                  AlertDialog alertDialog;
                  alertDialog = new AlertDialog.Builder(this).create();
                  alertDialog.setTitle("Your result:");
                  alertDialog.setMessage("True !Congratulations");
                  alertDialog.show();}
              else{ AlertDialog alertDialog;
              alertDialog = new AlertDialog.Builder(this).create();
              alertDialog.setTitle("Your result:");
              alertDialog.setMessage("false !You are idiot!");
              alertDialog.show();}


               break;

          case R.id.button2: 
              if( answers[0]==false){
                  AlertDialog alertDialog;
                  alertDialog = new AlertDialog.Builder(this).create();
                  alertDialog.setTitle("Your result:");
                  alertDialog.setMessage("Correct !Congratulations");
                  alertDialog.show();}
              else{ AlertDialog alertDialog;
              alertDialog = new AlertDialog.Builder(this).create();
              alertDialog.setTitle("Your result:");
              alertDialog.setMessage("Incorrect !You are idiot!");
              alertDialog.show();}


               break;


          }


    }

}

这是我的xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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=".MainActivity" 
    android:background="#99FFFF">

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="23dp"
        android:text="@string/num1"
        android:textAppearance="?android:attr/textAppearanceMedium" 
        android:background="#FFFFFF"/>

    <Button
        android:id="@+id/button2"
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_toRightOf="@+id/button1"
        android:text="@string/minus"
        android:background="#FFFFFF"/>

    <Button
        android:id="@+id/button1"
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/button2"
        android:background="#FFFFFF"
        android:text="@string/add" />

</RelativeLayout>

Answer 1

您将变量声明为数组

String[] questions ;
boolean[] answers;

然后你在没有初始化的情况下使用它们，所以java不知道数组的大小。

questions[0]="Are u hungry?";
answers[0]=true;

一种可能的解决方案是定义数组的大小：

String[] questions = new String[10]; // define the size of the array

另一个解决方案是使用ArrayList。

空白活动（Android）等待调试器

1 个答案: