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Android 開発でのアクティビティからアクティビティへの切り替えに助けが必要です。MainActivity アクティビティから MainMenu アクティビティに移動しようとしています。仕事をするために onclicklistener を実装しました。シミュレーターでアプリを実行すると問題なく動作しますが、onclicklistener で実装されたボタンをクリックしても何もしません。

package com.example.bmiworking;

import android.app.Activity;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;






            public class MainActivity extends Activity implements OnClickListener{
            /** Called when the activity is first created. */
            Button btn;
            @Override
            public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.activity_main);
                 btn = (Button)findViewById(R.id.homeClickHandler);
            }
            public void onClick(View v){
                if(v.getId() == R.id.homeClickHandler){
                startActivity(new Intent(this,MainMenu.class));
                }
            }


            public void calculateClickHandler(View view) {
             // make sure we handle the click of the calculator button

             if (view.getId() == R.id.calculateButton) {

              // get the references to the widgets
              EditText weightText = (EditText)findViewById(R.id.weightText);
              EditText heightText = (EditText)findViewById(R.id.heightText);
              TextView resultText = (TextView)findViewById(R.id.resultLabel);

              // get the users values from the widget references

              float weight = Float.parseFloat(weightText.getText().toString());
              float height = Float.parseFloat(heightText.getText().toString());

              // calculate the bmi value

              float bmiValue = calculateBMI(weight, height);

              // interpret the meaning of the bmi value
              String bmiInterpretation = interpretBMI(bmiValue);

              // now set the value in the result text

              resultText.setText(bmiValue + "-" + bmiInterpretation);
             }
            }

            // the formula to calculate the BMI index

            // check for http://en.wikipedia.org/wiki/Body_mass_index
            private float calculateBMI (float weight, float height) {

             return (float) (weight * 4.88 / (height * height));
            }


            // interpret what BMI means
            private String interpretBMI(float bmiValue) {

             if (bmiValue < 16) {
              return "Severely Underweight - See Weight Gain";
             } else if (bmiValue < 18.5) {

              return "Underweight - See Weight Gain";
             } else if (bmiValue < 25) {

              return "Normal - No Recomendations";
             } else if (bmiValue < 30) {

              return "Overweight - See Weight Loss";
             } else {
              return "Obese - See Weight Loss";
             }

            }


            @Override
            public void onClick(DialogInterface arg0, int arg1) {
                // TODO Auto-generated method stub

            }
        }



     <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".MainActivity" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:text="BMI Calculator"
            android:textAppearance="?android:attr/textAppearanceLarge" />

        <EditText
            android:id="@+id/weightText"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/textView2"
            android:layout_centerHorizontal="true"
            android:ems="10"
            android:inputType="numberDecimal" >

            <requestFocus />
        </EditText>

        <TextView
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/textView1"
            android:layout_centerHorizontal="true"
            android:text="@string/weightLabel"
            android:textAppearance="?android:attr/textAppearanceMedium" />

        <TextView
            android:id="@+id/textView3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/weightText"
            android:layout_centerHorizontal="true"
            android:text="@string/heightLabel"
            android:textAppearance="?android:attr/textAppearanceMedium" />

        <EditText
            android:id="@+id/heightText"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/weightText"
            android:layout_below="@+id/textView3"
            android:ems="10"
            android:inputType="numberDecimal" />

        <Button
            android:id="@+id/calculateButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/heightText"
            android:layout_centerHorizontal="true"
            android:onClick="calculateClickHandler"
            android:text="@string/calculateButton" />

        <TextView
            android:id="@+id/resultLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/calculateButton"
            android:layout_marginLeft="30dp"
            android:layout_marginTop="15dp"
            android:text="@string/emptyString"
            android:textAppearance="?android:attr/textAppearanceLarge" />

        <Button
            android:id="@+id/homeClickHandler"
            style="?android:attr/buttonStyleSmall"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true"
            android:text="@string/homeButton" />

    </RelativeLayout>

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

        <uses-sdk
            android:minSdkVersion="8"
            android:targetSdkVersion="17" />

        <application
            android:allowBackup="true"
            android:icon="@drawable/ic_launcher"
            android:label="@string/app_name"
            android:theme="@style/AppTheme" >
            <activity
                android:name="com.example.bmiworking.MainActivity"
                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:name="com.example.bmiworking.MainMenu"
                android:label="@string/app_name" >
                </activity>
        </application>

    </manifest>
4

1 に答える 1

2

間違った OnClickListener をインポートしているため、そのインポートを削除し、DialogInterface onClick メソッドも削除してください。

import android.view.View.OnClickListener;

以下「btn = (Button)findViewById(R.id.homeClickHandler);」と：

btn.setOnClickListener(this);

完了：

package com.example.bmiworking;

import android.app.Activity;
import android.content.DialogInterface;
import android.view.View.OnClickListener;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener {
/** Called when the activity is first created. */
Button btn;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    btn = (Button) findViewById(R.id.homeClickHandler);
    btn.setOnClickListener(this);
}

    @Override
public void onClick(View v) {
    if (v.getId() == R.id.homeClickHandler) {
        startActivity(new Intent(this, MainMenu.class));
    }
}

public void calculateClickHandler(View view) {
    // make sure we handle the click of the calculator button

    if (view.getId() == R.id.calculateButton) {

        // get the references to the widgets
        EditText weightText = (EditText) findViewById(R.id.weightText);
        EditText heightText = (EditText) findViewById(R.id.heightText);
        TextView resultText = (TextView) findViewById(R.id.resultLabel);

        // get the users values from the widget references

        float weight = Float.parseFloat(weightText.getText().toString());
        float height = Float.parseFloat(heightText.getText().toString());

        // calculate the bmi value

        float bmiValue = calculateBMI(weight, height);

        // interpret the meaning of the bmi value
        String bmiInterpretation = interpretBMI(bmiValue);

        // now set the value in the result text

        resultText.setText(bmiValue + "-" + bmiInterpretation);
    }
}

// the formula to calculate the BMI index

// check for http://en.wikipedia.org/wiki/Body_mass_index
private float calculateBMI(float weight, float height) {

    return (float) (weight * 4.88 / (height * height));
}

// interpret what BMI means
private String interpretBMI(float bmiValue) {

    if (bmiValue < 16) {
        return "Severely Underweight - See Weight Gain";
    } else if (bmiValue < 18.5) {

        return "Underweight - See Weight Gain";
    } else if (bmiValue < 25) {

        return "Normal - No Recomendations";
    } else if (bmiValue < 30) {

        return "Overweight - See Weight Loss";
    } else {
        return "Obese - See Weight Loss";
    }

}

}
于 2013-01-23T23:13:12.647 に答える