java应用程序在尝试新活动时崩溃

Question

我正在安卓上制作一个游戏，我想使用onClickListener中的循环来显示存储在String.xml中的对话框

我设置了一些代码，但应用程序崩溃了，eclipse中没有错误，但我不知道出了什么问题。所以请帮我检查代码。我将展示我可以在没有崩溃的情况下运行的代码（使用onClickListener，不使用循环）和导致崩溃的错误代码（使用我编写的循环，我猜那里有一些错误）

那个不会崩溃的

package com.group5.littlered;

import 安卓.app.Activity;
import 安卓.content.Intent;
import 安卓.media.MediaPlayer;
import 安卓.os.Bundle;
import 安卓.view.View;
import 安卓.view.Window;
import 安卓.view.WindowManager;
import 安卓.widget.Button;
import 安卓.widget.TextView;

public class Scene1 extends Activity{

MediaPlayer wovleshowling;
MediaPlayer bgm;

@Override
public void onBackPressed(){}

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
     //Remove title bar
    this.requestWindowFeature(Window.FEATURE_NO_TITLE);

    //Remove notification bar
    this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);


    setContentView(R.layout.activity_scene1);
    Intent intent = getIntent();

    Button next = (Button) findViewById(R.id.wtf);
    next.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            }



        }
);

    //BGM
    bgm = MediaPlayer.create(Scene1.this, R.raw.unsettledthoughts);
    bgm.setLooping(true);
    bgm.start();

    //wovleshowling
    wovleshowling = MediaPlayer.create(Scene1.this, R.raw.wolveshowling);
    wovleshowling.setLooping(false);
    wovleshowling.start();

}

}

坠毁的那一个：

    package com.group5.littlered;

import 安卓.app.Activity;
import 安卓.content.Intent;
import 安卓.media.MediaPlayer;
import 安卓.os.Bundle;
import 安卓.view.View;
import 安卓.view.Window;
import 安卓.view.WindowManager;
import 安卓.widget.Button;
import 安卓.widget.TextView;

public class Scene1 extends Activity{

MediaPlayer wovleshowling;
MediaPlayer bgm;

int position = 0;
String [] conversation = getResources().getStringArray(R.array.scene1);
TextView frame = (TextView) findViewById(R.id.textView1);

@Override
public void onBackPressed(){}

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
     //Remove title bar
    this.requestWindowFeature(Window.FEATURE_NO_TITLE);

    //Remove notification bar
    this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);


    setContentView(R.layout.activity_scene1);
    Intent intent = getIntent();

    Button next = (Button) findViewById(R.id.wtf);
    next.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            if (position < 6){

                String sentence = conversation[position];

            frame.setText(sentence + "");
            position ++ ;
            }
            }



        }
);

    //BGM
    bgm = MediaPlayer.create(Scene1.this, R.raw.unsettledthoughts);
    bgm.setLooping(true);
    bgm.start();

    //wovleshowling
    wovleshowling = MediaPlayer.create(Scene1.this, R.raw.wolveshowling);
    wovleshowling.setLooping(false);
    wovleshowling.start();





}

}

Answer 1

您应该在onCreate（）中更新UI，因此在onCreate（）中将TextView与xml绑定

public class Scene1 extends Activity{

MediaPlayer wovleshowling;
MediaPlayer bgm;

int position = 0;
String [] conversation = getResources().getStringArray(R.array.scene1);
TextView frame;

@Override
public void onBackPressed(){}

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
     frame = (TextView) findViewById(R.id.textView1);//this should be inside the onCreate() method
     //Remove title bar
    this.requestWindowFeature(Window.FEATURE_NO_TITLE);

    //Remove notification bar
    this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);


    setContentView(R.layout.activity_scene1);
    Intent intent = getIntent();

    Button next = (Button) findViewById(R.id.wtf);
    next.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            if (position < 6){

                String sentence = conversation[position];

            frame.setText(sentence + "");
            position ++ ;
            }
            }



        }
);

    //BGM
    bgm = MediaPlayer.create(Scene1.this, R.raw.unsettledthoughts);
    bgm.setLooping(true);
    bgm.start();

    //wovleshowling
    wovleshowling = MediaPlayer.create(Scene1.this, R.raw.wolveshowling);
    wovleshowling.setLooping(false);
    wovleshowling.start();

}

}

Answer 2

TextView框架=（TextView）findViewById（R.id.textView1） 必须位于创建应用程序后调用的方法onCreate（）内

Answer 3

请走开

TextView frame = (TextView) findViewById(R.id.textView1);

setContentView调用后的内部onCreate（）

由于您没有粘贴日志，我假设这会导致onClick（）函数中出现NullPointerException