Question

我正在尝试通过Bundle将9个字符串从一个java类传递到另一个类。但是在另一个屏幕中，分配给最后一个额外值的值将被覆盖到所有其他字符串。

的Class1

public class HomeScreen extends AppCompatActivity {

public  static String  Buy_Price;
public  static String  Sell_Price;
public  static String  QUANTITY;
public  static String  BROKERAGE;
public  static String  ActualProfitLoss_String;
public  static String  TurnOver_String;
public  static String  STT_String;
public  static String  ServiceTax_String;
public  static String  TotalCharge_String;
public  static String  x;
private static  String Strin ;

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

public void calculateProfit(View view) {
    Intent intent = new Intent(this, displayProfit.class);
    Bundle extras =new Bundle();
    EditText editText=(EditText) findViewById(R.id.editText);
    EditText editText4=(EditText) findViewById(R.id.editText4);
    EditText editText2=(EditText) findViewById(R.id.editText2);
    EditText editText3=(EditText) findViewById(R.id.editText3);

    String buyPriceString = editText3.getText().toString();
    Float BuyPrice =  Float.parseFloat(buyPriceString);
    String quantityString = editText2.getText().toString();
    Float Quantity =  Float.parseFloat(quantityString);
    String sellPriceString = editText4.getText().toString();
    Float SellPrice =  Float.parseFloat(sellPriceString);
    String brokerageString = editText.getText().toString();
    Float Brokerage =  Float.parseFloat(brokerageString);

    double TurnOver=(BuyPrice*Quantity)+(SellPrice*Quantity);
    double Sell1 =SellPrice-(SellPrice*(Brokerage/100));
    double Buy1 = BuyPrice+(BuyPrice*(Brokerage/100));
    double TotalBrokerage = ((Sell1*.03)+(Buy1*0.3));
    double STT = (Quantity*(SellPrice-(SellPrice*(Brokerage/100))))*(.025/100);
    double TrnxChrge = TurnOver*(0.00275/100);
    double ServiceTax = (TotalBrokerage+STT)*(15/100);
    double SEBICharge = (TurnOver*(.0002/100));
    double TotalCharge = ServiceTax+TrnxChrge+SEBICharge+STT;
    double NetProfit = (Sell1-Buy1)*Quantity;
    double ActualProfitLoss = (NetProfit -TotalCharge);


    String ActualProfitLossString=Double.toString(ActualProfitLoss);
    String TurnOverString=Double.toString(TurnOver);
    String STTString=Double.toString(STT);
    String ServiceTaxString=Double.toString(ServiceTax);
    String TotalChargeString=Double.toString(TotalCharge);


    extras.putString(ActualProfitLoss_String,ActualProfitLossString);
    extras.putString(TurnOver_String,TurnOverString);
    extras.putString(STT_String,STTString);
    extras.putString(ServiceTax_String,ServiceTaxString);
    extras.putString(TotalCharge_String,TotalChargeString);
    extras.putString(Buy_Price,buyPriceString);
    extras.putString(Sell_Price,sellPriceString);
    extras.putString(BROKERAGE,brokerageString);
    extras.putString(QUANTITY,quantityString);
    intent.putExtras(extras);

    startActivity(intent);

}

第2课：

public class displayProfit extends AppCompatActivity {


private static  String Strin ;

protected void onCreate(Bundle savedInstanceState) {
    Log.d(Strin, "buyPrice :::");
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_display_profit);

    Intent intent =getIntent();
    Bundle extras = intent.getBundleExtra(HomeScreen.x);
    String Buy_Price = extras.getString(HomeScreen.Buy_Price);
    String Sell_Price = extras.getString(HomeScreen.Sell_Price);
    String QUANTITY = extras.getString(HomeScreen.QUANTITY);
    String BROKERAGE = extras.getString(HomeScreen.BROKERAGE);
    String ActualProfitLoss_String = extras.getString(HomeScreen.ActualProfitLoss_String);
    String TurnOver_String = extras.getString(HomeScreen.TurnOver_String);
    String STT_String = extras.getString(HomeScreen.STT_String);
    String ServiceTax_String = extras.getString(HomeScreen.ServiceTax_String);
    String TotalCharge_String = extras.getString(HomeScreen.TotalCharge_String);


    TextView Buy_Price1= (TextView) findViewById(R.id.Buy_Price1);
    TextView Sell_Price1= (TextView) findViewById(R.id.Sell_Price1);
    TextView QUANTITY1= (TextView) findViewById(R.id.QUANTITY1);
    TextView BROKERAGE1= (TextView) findViewById(R.id.BROKERAGE1);
    TextView ActualProfitLoss_String1= (TextView) findViewById(R.id.ActualProfitLoss_String1);
    TextView TurnOver_String1= (TextView) findViewById(R.id.TurnOver_String1);
    TextView STT_String1= (TextView) findViewById(R.id.STT_String1);
    TextView ServiceTax_String1= (TextView) findViewById(R.id.ServiceTax_String1);
    TextView TotalCharge_String1= (TextView) findViewById(R.id.TotalCharge_String1);


    Buy_Price1.setText(Buy_Price);
    Sell_Price1.setText(Sell_Price);
    QUANTITY1.setText(QUANTITY);
    BROKERAGE1.setText(BROKERAGE);
    ActualProfitLoss_String1.setText(ActualProfitLoss_String);
    TurnOver_String1.setText(TurnOver_String);
    STT_String1.setText(STT_String);
    ServiceTax_String1.setText(ServiceTax_String);
    TotalCharge_String1.setText(TotalCharge_String);

}

}

在class2的最后，我放置了log，发现分配给QUANTITY的Value正在为所有字符串填充。

请澄清以上内容。如果您需要更多代码，则会共享相同内容。

按照回答
中的建议更改Class1后记录相同内容
W / IInputConnectionWrapper：在非活动的InputConnection上的finishComposingText      W / IInputConnectionWrapper：在非活动的InputConnection上的finishComposingText      W / IInputConnectionWrapper：在非活动的InputConnection上的finishComposingText      我/艺术：背景粘性并发标记扫描GC释放25273（2MB）AllocSpace对象，15（264KB）LOS对象，44％免费，4MB / 8MB，暂停14.345ms总计168.562ms
       [ 02-20 23:21:14.614  3314: 3314 D/         ]
buyPrice :::

[02-20 23：21：14.861 3314：3314 D /]      NOTNULL ::::::      D / AndroidRuntime：关闭VM
       --------- beginning of crash
E / AndroidRuntime：致命异常：主要处理：com.test.tax，PID：3314 java.lang.RuntimeException：无法启动活动ComponentInfo {com.test.tax/com.test.tax.displayProfit}：java.lang.NullPointerException：尝试调用虚方法'java.lang.String android.os.Bundle。 null对象引用上的getString（java.lang.String）' 在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2646）在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2707）在android.app.ActivityThread.-wrap12（ActivityThread.java）在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1460）在android.os.Handler.dispatchMessage（Handler.java:102）在android.os.Looper.loop（Looper.java:154）在android.app.ActivityThread.main（ActivityThread.java:6077） at java.lang.reflect.Method.invoke（Native Method）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:865）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:755）引起：java.lang.NullPointerException：尝试在空对象引用上调用虚方法'java.lang.String android.os.Bundle.getString（java.lang.String）' 在com.test.tax.displayProfit.onCreate（displayProfit.java:29）在android.app.Activity.performCreate（Activity.java:6662）在android.app.Instrumentation.callActivityOnCreate（Instrumentation.java:1118）在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2599）在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2707）在android.app.ActivityThread.-wrap12（ActivityThread.java）在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1460）在android.os.Handler.dispatchMessage（Handler.java:102）在android.os.Looper.loop（Looper.java:154）在android.app.ActivityThread.main（ActivityThread.java:6077） at java.lang.reflect.Method.invoke（Native Method）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:865）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:755）断开与目标VM的连接，地址：'localhost：8625'，transport：'socket'

Answer 1

只需初始化您用于将项目添加到具有唯一值的public static String的所有上述Bundle，否则它们将相互覆盖。例如

public  static String  Buy_Price = "a";
public  static String  Sell_Price = "b";
public  static String  QUANTITY = "c";
public  static String  BROKERAGE = "d";
public  static String  ActualProfitLoss_String = "e";
public  static String  TurnOver_String = "f";
public  static String  STT_String = "g";
public  static String  ServiceTax_String = "h";
public  static String  TotalCharge_String = "i";
public  static String  x =  = "j";

此外，他们理想情况下应为public static final String。请考虑使用一致的命名约定（TOTAL_CHARGE，TURN_OVER）。

您可以将Bundle想象为地图，如果您使用相同的键放置值，则会覆盖这些值。这就是为什么你为所有键获得了QUANTITY的值的原因，因为所有的键都是null（相等）而QUANTITY是你放在Bundle中的最后一个键。

编辑：对于NullPointerException。

在{1}}方法中的第1类（HomeScreen）中，您将calculateProfit(View view)放入Bundle而没有按键。

Intent

然后在intent.putExtras(extras);内的第2课（displayProfit）中，您可以使用密钥从onCreate(Bundle savedInstanceState)获取Bundle。

Intent

所以在HomeScreen中使用相同的密钥来添加额外内容，如此

intent.getBundleExtra(HomeScreen.x);

在Bundle中传递多个值，在最后一个String中分配的值将传递给所有字符串

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1 个答案: