Question

我正在Android Studio中制作应用程序，如果您在手机上打开应用程序，则会看到Launcer活动。我有一个按钮，可以将您带到游戏所在的新活动。单击“开始”按钮后，应用程序将关闭，不会转到其他活动。那是为什么？

这是我的Launcher活动代码：

package joenio.sirname;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;

public class SirName_launcher extends AppCompatActivity {

public static Button button_start;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_sir_name_launcher);
    StartButton();
}

public void StartButton(){
    button_start = (Button) findViewById(R.id.button_start);

    button_start.setOnClickListener(
            new View.OnClickListener() {
                @Override
                public void onClick(View v) {

                    Intent intent1 = new Intent("joenio.sirname.Game");
                    startActivity(intent1);
                }

            }
    );



}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_sir_name_launcher, menu);
    return true;

}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
 }
}

这是第二项活动的代码：

package joenio.sirname;


import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import java.util.ArrayList;
import android.widget.Toast;


public class Game extends AppCompatActivity {
    public static EditText editText_surname;
    public static TextView textView_name;
    public static Button button_check;

int x =0; //to keep track of qustions






//Context editText_this = this;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_game);
    Displayquestions();
}
public void Displayquestions(){


    final ArrayList<String> mQuestionList = new ArrayList<>();


    mQuestionList.add("1+2");
    mQuestionList.add("6+8");
    mQuestionList.add("5 * 6");
    mQuestionList.add("8*5");
    mQuestionList.add("6+16");
    mQuestionList.add("18-5");



    textView_displayquestion.setText((mQuestionList.get(x)));//displayquestion is textview




    final ArrayList<String> mAnswerList=new ArrayList<>();

    mAnswerList.add("3");
    mAnswerList.add("14");
    mAnswerList.add("30");
    mAnswerList.add("40");
    mAnswerList.add("22");
    mAnswerList.add("13");






    //button_check is the button when user click it will first check answer and than move to next question if answer is correct


    button_check.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            //editText_this;
            String answer = editText_ans.getText().toString();
            if (answer.equals(mAnswerList.get(x))) {
                x = x + 1;
                textView_displayquestion.setText(mQuestionList.get(x)); //answer is correct display next quesion
                Toast.makeText(getApplication().getBaseContext(),
                        (R.string.Nice), Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(getApplication().getBaseContext(),
                        (R.string.tryagain), Toast.LENGTH_SHORT).show();

            }
        }
    });


    }
}

Answer 1

在按钮单击中，更改以下代码。

Intent intent1 = new Intent(SirName_launcher.this, Game.class);
startActivity(intent1);

并在你的Manifest文件中添加新的Game Activity。

Answer 2

您无法初始化必须导致self.myTabbar!.addSubview(button)的{{1}}和TextView。

像这样更改您的Button活动

NullPointerException

不会弹出新布局

2 个答案: