通过Intent方法发送整数

Question

我见过很多使用intent()将数值添加到int整数值的方法。然而，我的工作不太好。有人有什么建议吗？我使用intent()方法通过一个按钮从一个单独的活动中发送一个整数值。按下按钮时，该值应将活动增加1。以下是我目前所拥有的：

public class GameEmulator extends Activity{
//Creating two static values to pass strings from SelectPlayer classes
public final static String value = "EMPTY_VALUE";
public final static String value2 = "EMPTY_VALUE2";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout);

//Button created to go back to AddPlayer activity
Button addplayer1 = findViewById(R.id.button9);
addplayer1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(GameEmulator.this, AddPlayer.class);
startActivity(i);
}
});
Button viewScores = findViewById(R.id.viewScore);
viewScores.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(GameEmulator.this, MainActivity.class);
startActivity(intent);
}
});
//Button for player one winning
Button winButtonOne = findViewById(R.id.button7);
winButtonOne.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int scored = 1;
Intent intent = new Intent(GameEmulator.this, Scoreboard.class);
intent.putExtra("MY_KEY", scored);
startActivity(intent);
}
});
TextView textView =  findViewById(R.id.name1);
TextView textview2 = findViewById(R.id.name2);
//setting value retrieved from SleectPlayer and Displaying it in textView
Intent intent = getIntent();
String extra = intent.getStringExtra(value);
textView.setText(extra);
//setting value retrieved from SleectPlayer2 and Displaying it in textView2
Intent in = getIntent();
String extra1 = in.getStringExtra(value2);
textview2.setText(extra1);
}
}
public class Scoreboard extends Activity{
public static ArrayAdapter<String> adapter2;
public static ArrayAdapter<String> adapter3;
public static ArrayList<String> list2 = new ArrayList<>();
public static ArrayList<String> list3 = new ArrayList<>();
ListView selectView3;
ListView selectView4;
public static  int losses1 = 0;
public static  int ties1 = 0;
public static  int losses2 = 0;
public static  int ties2 = 0;
public final static String value2 = "EMPTY_VALUE2";


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

selectView3 = findViewById(R.id.selectview3);
selectView3.setVisibility(View.VISIBLE);
selectView4 = findViewById(R.id.selectview4);
selectView4.setVisibility(View.VISIBLE);

//Using adapter for ListView menu
adapter2 = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, list2);
selectView3.setAdapter(adapter2);
//Using intent to retrieve string from AddPlayer Activity
Intent i = getIntent();
int score = getIntent().getIntExtra("MY_KEY", 1);
String data = i.getStringExtra("text_key");
if(data != null){
list2.add("Player 1"+"n"+"Name: "+data+"n"+"Wins: "+ score +"n"+"Losses: "+ losses1+"n"+"Ties: "+ ties1);
}
if(data != ""){
changeList();
}
adapter3 = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, list3);
selectView4.setAdapter(adapter3);
Intent intent = getIntent();
String extra= intent.getStringExtra(value2);
if(extra != null) {
list3.add("Player 2" + "n" + "Name: " + extra + "n" + "Wins: " + score + "n" + "Losses: " + losses2 + "n" + "Ties: " + ties2);
}
if(data != ""){
changeList();
}
}
public  void changeList()
{
adapter2.notifyDataSetChanged();
}
}

Answer 1

此行：

String data = i.getStringExtra("text_key");

使data = null，因为您没有在最初的意图中使用关键字"text_key"添加额外的值
因此此代码：

list2.add("Player 1"+"n"+"Name: "+data+"n"+"Wins: "+ score +"n"+"Losses: "+ losses1+"n"+"Ties: "+ ties1);

从未执行