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Android

Posted by Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

Cannot instantiate the type ShakeDetector

I am following the directions just as it is describes but for some reason I get an error when writing this line:

mShakeDetector = new ShakeDetector(new OnShakeListener() {

        @Override
        public void onShake() {
            handleNewAnswer();
        }
    });
}

4 Answers

Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points
Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

So I just solved the code by deleting the <ShakeDetector> line that was placed right after the public class MainActivity now my project is free of errors.

Gunjeet Hattar
Gunjeet Hattar
14,483 Points
Gunjeet Hattar
Gunjeet Hattar
14,483 Points

Did you organise your imports and declared a ShakeDetector data type at the top.

If you could tell us the exact error by looking in the error intellisense or the console/logcat tab it would help identify better

Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

This is all it says: Cannot instantiate the type ShakeDetector ------ Thats on the line: mShakeDetector = new ShakeDetector(new OnShakeListener() {

The method of onShake() on type of new OnShakeListener(){} must override or implement a supertype method----Thats on the line: @Override public void onShake() { handleNewAnswer(); } }); }

Gunjeet Hattar
Gunjeet Hattar
14,483 Points
Gunjeet Hattar
Gunjeet Hattar
14,483 Points

Strange. Did you declare a ShakeDetector mShakeDetector; at the beginning?

Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

This declares it right? private ShakeDetector mShakeDetector;

Gunjeet Hattar
Gunjeet Hattar
14,483 Points

Yeah seems like its correct. Now check if you added the ShakeDetector.java class, that you downloaded from Treehouse in the right place. It should be in the same package level as your MainActivity.java class

Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

It's in the right level

Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points
Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

package com.example.crystalball;

import android.app.Activity; import android.graphics.drawable.AnimationDrawable; import android.hardware.Sensor; import android.hardware.SensorManager; import android.media.MediaPlayer; import android.media.MediaPlayer.OnCompletionListener; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.view.animation.AlphaAnimation; import android.widget.ImageView; import android.widget.TextView;

import com.example.crystalball.ShakeDetector.OnShakeListener;

public class MainActivity<ShakeDetector> extends Activity { private CrystalBall mCrystalBall = new CrystalBall(); private TextView mAnswerLabel; private ImageView mCrystalBalImage; private SensorManager mSensorManager; private Sensor mAccelerometer; private ShakeDetector mShakeDetector;

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

    //Assign the view from the layout file
    mAnswerLabel = (TextView) findViewById(R.id.textView1);
    mCrystalBalImage = (ImageView) findViewById(R.id.imageView1);

    mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
    mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
    mShakeDetector = new ShakeDetector(new OnShakeListener() {

        @Override
        public void onShake() {
            handleNewAnswer();
        }
    });

}
Terrence Smith Jr.
Terrence Smith Jr.
1,134 Points

This part is the only problem it says I can't instantiate: mShakeDetector = new ShakeDetector(new OnShakeListener() {