Question

我正在做一个简单的Android应用程序（一个度量转换器），我正在使用两个活动：第一个活动是主应用程序，第二个活动用于显示结果。

当我输入值时，选择转换类型（例如码到厘米）并单击结果按钮，结果仅出现在第一个活动（而不是第二个活动）中。

这是我的代码：

ActivityMain.java

package displayinsecact.project;

import android.app.*;
import android.content.Intent;
import android.os.*;
import android.view.*;
import android.widget.*;

public class ActivityMain extends Activity{

private EditText etxt;
private TextView txtViewRes;
private CheckBox chkBoxYarCen, chkBoxCenYar, chkBoxYarMet, chkBoxMetYar,     chkBoxYarPie, chkBoxPieYar;

private ConversorMedidas current;

public void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    initialUISetup();

    txtViewRes=(TextView)findViewById(R.id.txtViewRes);

}

public void initialUISetup(){
    etxt=(EditText)findViewById(R.id.etxt);
    txtViewRes=(TextView)findViewById(R.id.txtViewRes);
    chkBoxYarCen=(CheckBox)findViewById(R.id.chkBoxYarCen);
    chkBoxCenYar=(CheckBox)findViewById(R.id.chkBoxCenYar);
    chkBoxYarMet=(CheckBox)findViewById(R.id.chkBoxYarMet);
    chkBoxMetYar=(CheckBox)findViewById(R.id.chkBoxMetYar);
    chkBoxYarPie=(CheckBox)findViewById(R.id.chkBoxYarPie);
    chkBoxPieYar=(CheckBox)findViewById(R.id.chkBoxPieYar);
}

public void exchange(View v){
    double aux=0;

    if(chkBoxYarCen.isChecked()==true){
        current=new convYarCen();
            aux=current.yardasCentimetros(Double.parseDouble(etxt.getText().toString()));
    }
    if(chkBoxCenYar.isChecked()==true){
        current=new convYarCen();
        aux=current.yardasMetros(Double.parseDouble(etxt.getText().toString()));
    }
    if(chkBoxYarMet.isChecked()==true){
        current=new convYarMet();
        aux=current.yardasMetros(Double.parseDouble(etxt.getText().toString()));
    }
    if(chkBoxMetYar.isChecked()==true){
        current=new convYarMet();
            aux=current.yardasCentimetros(Double.parseDouble(etxt.getText().toString()));
    }
    if(chkBoxYarPie.isChecked()==true){
        current=new convYarPie();
            aux=current.yardasCentimetros(Double.parseDouble(etxt.getText().toString()));
    }
    if(chkBoxPieYar.isChecked()==true){
        current=new convYarPie();
        aux=current.yardasMetros(Double.parseDouble(etxt.getText().toString()));
    }

    txtViewRes.setText(String.valueOf(aux));
}

String contenido;

public void showThirdActivity(View v){

    contenido=txtViewRes.getText().toString();

    Intent i=new Intent(this, ResultadoActivity.class);
    i.putExtra("resultado", contenido);
    startActivity(i);
}

}

ResultActivity.java

package displayinsecact.project;

import android.app.Activity;
import android.os.*;
import android.widget.*;

public class ResultadoActivity extends Activity{

TextView tvDatosRecibidos;
String cadena;

public void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.resultado);
    tvDatosRecibidos=(TextView)findViewById(R.id.tvDatosRecibidos);

    Bundle recogerDatos=getIntent().getExtras();
    cadena=recogerDatos.getString("resultado");

    tvDatosRecibidos.setText(cadena);
}

}

main.xml中

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="This is the second activity" />

<TextView 
    android:id="@+id/txtViewData"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Input Data"
    />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/etxt"><requestFocus></requestFocus>
</EditText>

<!--     
chkBoxYarCen, chkBoxCenYar, chkBoxYarMet, chkBoxMetYar, chkBoxYarPie, chkBoxPieYar;  
 -->

<CheckBox 
    android:id="@+id/chkBoxYarCen"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Yards to Centimetres"
    />

<CheckBox 
    android:id="@+id/chkBoxCenYar"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Centimetres to Yards"
    />

<CheckBox
    android:id="@+id/chkBoxYarMet"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Yards to Metres"
    />

<CheckBox
    android:id="@+id/chkBoxMetYar"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Foot to Yards"
    />

<CheckBox 
    android:id="@+id/chkBoxYarPie"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Yards to Foots"        
    />

<CheckBox 
    android:id="@+id/chkBoxPieYar"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Foots to Yards"  
    />

<!-- Botones -->
<Button 
    android:id="@+id/btnOpe"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Exchange"
    android:onClick="exchange"
    />

<TextView 
    android:id="@+id/txtViewRes"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Resultado"
    />

resultado.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView 
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Datos recibidos de la actividad anterior"
    />

<TextView
    android:id="@+id/tvDatosRecibidos"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />

的AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="displayinsecact.project"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk android:minSdkVersion="7" />

<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >
    <activity
        android:name=".ActivityMain"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity 
        android:label="Resultado Activity"
        android:name=".Resultadoctivity">
        <intent-filter >
            <action android:name=".Resultadoctivity"/>
            <category android:name="android.intent.category.DEFAULT"/>
        </intent-filter>
    </activity>
</application>

很抱歉给您带来不便。

Answer 1

在第一项活动中更改您的代码

 Intent i=new Intent(this, ResultadoActivity.class);
 Bundle b =new Bundle();
 b.putString("resultado", contenido);
 i.putExtras(b);
 startActivity(i);

Android：在两个活动之间发送参数失败

1 个答案: