Android应用程序-没有此类方法异常

Question

I am trying to create an android app that involves pressing a button that takes a picture. My code is clean without any warnings or errors but when I run it on the emulator, and as soon as I press the photo button in the app, it says that your app has stopped.When I check the log file for the explanation it gives me the following

Any help would be appreciated. Thank you in advance.

    07-27 20:44:11.676: E/AndroidRuntime(453): FATAL EXCEPTION: main
    07-27 20:44:11.676: E/AndroidRuntime(453): java.lang.IllegalStateException: Could not find a method dispatchTakePhotoIntent(View) in the activity class com.example.mydressingroom.MainActivity for onClick handler on view class android.widget.Button
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.view.View$1.onClick(View.java:3026)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.view.View.performClick(View.java:3480)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.view.View$PerformClick.run(View.java:13983)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.os.Handler.handleCallback(Handler.java:605)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.os.Handler.dispatchMessage(Handler.java:92)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.os.Looper.loop(Looper.java:137)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.app.ActivityThread.main(ActivityThread.java:4340)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at java.lang.reflect.Method.invokeNative(Native Method)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at java.lang.reflect.Method.invoke(Method.java:511)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at dalvik.system.NativeStart.main(Native Method)
    07-27 20:44:11.676: E/AndroidRuntime(453): Caused by: java.lang.NoSuchMethodException: dispatchTakePhotoIntent [class android.view.View]
    07-27 20:44:11.676: E/AndroidRuntime(453):  at java.lang.Class.getConstructorOrMethod(Class.java:460)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at java.lang.Class.getMethod(Class.java:915)
    07-27 20:44:11.676: E/AndroidRuntime(453):  at android.view.View$1.onClick(View.java:3019)
    07-27 20:44:11.676: E/AndroidRuntime(453):  ... 11 more

Here is my code

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.provider.MediaStore;

public class MainActivity extends Activity {

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


    /** Called when the user clicks the Photo button */
    public void dispatchTakePhotoIntent(int actionCode) {
          Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
          startActivityForResult(takePhotoIntent, actionCode);
    }

}

Answer 1

the error says: could not find a method dispatchTakePhotoIntent( View )

You a calling dispatchTakePhotoIntent with a View object as an argument to it whereas in your code you have defined:

public void dispatchTakePhotoIntent(int actionCode) 

which takes an integer as an argument.

There is a problem in the way you are calling your method inside your code.

Answer 2

Could not find a method dispatchTakePhotoIntent(View) in the activity class com.example.mydressingroom.MainActivity for onClick handler on view class android.widget.Button

It seems you might be sending a View to the method, instead of sending a integer as you have defined in the method attribute.

Answer 3

create a constant in the class which calls the method

  private static final int TAKE_PHOTO_REQUEST = 100;

and call the method as

  dispatchTakePhotoIntent(TAKE_PHOTO_REQUEST);

and inside your method test for the request code:

  public void dispatchTakePhotoIntent(int actionCode) {
    if (actionCode == 100) {
        Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(takePhotoIntent, actionCode);
    }
  }

and the problem is that you are calling the method by passing to it the view in which the image is being rendered/displayed rather than the action which you want to carry. So the compiler found a call to the method of type dispatchTakePhotoIntent(View) which it could not find in your code since you have defined dispatchTakePhotoIntent(int) .

if you are developing in eclipse you should be getting an error in your code (a red cross on the line where the error is).