Question

Below is the Java file that I used. All of the code works really well, but the error above still lingers. Can anyone see the problem?

package tip.calculator;

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

public class TipCalculator extends Activity 
{
    private Button enter;
    EditText myEditField;
    EditText myEditField2;
    float percentage = 0;
    float percentageInp = 0;
    float billAmount = 0;
    double output = 0; 
    String output1 = "";
    Button clearButton ;
    TextView textView;

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

        myEditField = (EditText) findViewById(R.id.percentText);
        enter = (Button)findViewById(R.id.button1);
        myEditField2 = (EditText) findViewById(R.id.billText);
        clearButton = (Button) findViewById(R.id.clearButton);

        enter.setOnClickListener( new OnClickListener() {
            public void onClick(View v) {
                TextView errors;
                textView = (TextView) findViewById(R.id.textView1);
                errors = (TextView) findViewById(R.id.textView4); 
                int a = 0;
                if(myEditField2.getText().toString().equals("")) {
                    errors.setText("Error");
                } else {
                    a++;
                }

                if(myEditField.getText().toString().equals("")){
                    errors.setText("Error");
                } else {
                    a++;
                }

                if(a == 2) {
                    percentageInp = Float.parseFloat(myEditField.getText().toString());
                    billAmount = Float.parseFloat(myEditField2.getText().toString());
                    percentage = ((float)percentageInp /100);

                    output = (double)(billAmount * percentage);

                    double result = output * 100;
                    result = Math.round(result);
                    result = result / 100;

                    output1 = Double.toString(result);

                    View.setText(output1 + " $");
                    errors.setText("");
                }
            }
        });

        clearButton.setOnClickListener( new OnClickListener() {
            public void onClick(View v) {
                TextView errors;
                textView = (TextView) findViewById(R.id.textView1);
                errors = (TextView) findViewById(R.id.textView4); 
                int a = 0;

                if (myEditField2.getText().toString().equals("")) {
                    myEditField.setText("");
                    percentage = 0;
                    percentageInp = 0;
                    billAmount = 0;
                    output = 0; 
                    textView.setText("");
                    output1 = "";
                } else {
                    a++;
                }

                if(myEditField.getText().toString().equals("")) {
                    myEditField2.setText("");
                    percentage = 0;
                    percentageInp = 0;
                    billAmount = 0;
                    output = 0; 
                    output1 = "";
                    textView.setText("");
                 } else {
                    a++;
                 }

                 if (a == 2) {
                    myEditField.setText("");
                    myEditField2.setText("");
                    percentage = 0;
                    percentageInp = 0;
                    billAmount = 0;
                    output = 0; 
                    output1 = "";

                    textView.setText("");
                    errors.setText("");
                }
            }
        });
    }
}

Here is the logcat, where I get an error I don’t understand at all. I never call the method onEnterClick()?

08-02 21:17:37.205: E/AndroidRuntime(27185): FATAL EXCEPTION: main
08-02 21:17:37.205: E/AndroidRuntime(27185): java.lang.IllegalStateException: Could not find a method onEnterClick(View) in the activity class tip.calculator.TipCalculator for onClick handler on view class android.widget.RelativeLayout with id 'errorText'
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.view.View$1.onClick(View.java:3085)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.view.View.performClick(View.java:3620)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.view.View$PerformClick.run(View.java:14292)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.os.Handler.handleCallback(Handler.java:605)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.os.Handler.dispatchMessage(Handler.java:92)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.os.Looper.loop(Looper.java:137)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.app.ActivityThread.main(ActivityThread.java:4507)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at java.lang.reflect.Method.invokeNative(Native Method)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at java.lang.reflect.Method.invoke(Method.java:511)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at dalvik.system.NativeStart.main(Native Method)
08-02 21:17:37.205: E/AndroidRuntime(27185): Caused by: java.lang.NoSuchMethodException: onEnterClick [class android.view.View]
08-02 21:17:37.205: E/AndroidRuntime(27185):    at java.lang.Class.getConstructorOrMethod(Class.java:460)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at java.lang.Class.getMethod(Class.java:915)
08-02 21:17:37.205: E/AndroidRuntime(27185):    at android.view.View$1.onClick(View.java:3078)
08-02 21:17:37.205: E/AndroidRuntime(27185):    ... 11 more

Answer 1

I think you have defined the onclick method in the XML Layout also. And you have written the onclick listener in the program. Remove the following line from your xml layout and your program works fine:

android:onclick="onEnterClick"