Android Studio: Error when creating signed apk

Question

I keep getting this error when I try to generate a signed APK

Error:Error: This class should provide a default constructor (a public constructor with no arguments) (com.STMReport.Viewer.FirmaDigital) [Instantiatable]

Can anyone help me with some advice of what is causing this? I investigated about this issue and it has to do with the super() on the default constructor but when I tried to remove the line of code it gives me another error

Error:(24, 42) error: no suitable constructor found for View(no arguments)
constructor View.View(Context) is not applicable

Here is my class:

package com.STMReport.Viewer;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;

import android.view.MotionEvent;
import android.view.View;


public class FirmaDigital extends View {

private Bitmap mBitmap;
private Canvas  mCanvas;
private Path    mPath;
private Paint   mBitmapPaint;
private Paint   mPaint;
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;


public FirmaDigital(Context context) {
    super(context);

    mPath = new Path();
    mBitmapPaint = new Paint(Paint.DITHER_FLAG);

    mPaint = new Paint();
    mPaint.setAntiAlias(true);
    mPaint.setDither(true);
    mPaint.setColor(0xFF000000);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setStrokeJoin(Paint.Join.ROUND);
    mPaint.setStrokeCap(Paint.Cap.ROUND);
    mPaint.setStrokeWidth(3);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(w, h, oldw, oldh);
    mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
    mCanvas = new Canvas(mBitmap);
}

@Override
protected void onDraw(Canvas canvas) {
    canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);

    canvas.drawPath(mPath, mPaint);
}

private void touch_starto(float x, float y) {
    mPath.reset();
    mPath.moveTo(x, y);
    mX = x;
    mY = y;
}

private void touch_mover(float x, float y) {
    float dx = Math.abs(x - mX);
    float dy = Math.abs(y - mY);
    if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
        mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
        mX = x;
        mY = y;
    }
}

private void touch_ups() {
    mPath.lineTo(mX, mY);
    // commit the path to our offscreen
    mCanvas.drawPath(mPath, mPaint);
    // kill this so we don't double draw
    mPath.reset();
}
@Override
public boolean onTouchEvent(MotionEvent event) {
    float x = event.getX();
    float y = event.getY();

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            touch_starto(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_MOVE:
            touch_mover(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_UP:
            touch_ups();
            invalidate();
            break;
    }
 return true;
}

}

I forgot to add how I use the class:

public class FirmaActivity extends Activity {

RelativeLayout parent;
FirmaDigital firma;
@Override

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_firma);
    parent = (RelativeLayout)findViewById(R.id.FirmaLayout);
    firma = new FirmaDigital(this);
    parent.addView(firma);
}
}

Any help would be appreciated Thanks!

Best solution work for me is here [check this](http://stackoverflow.com/questions/17420637/error-non-default-constructors-in-fragments/39608360#39608360) — Naeem Ibrahim, Sep 21 '16 at 05:58

score 0 · Accepted Answer · answered Dec 09 '14 at 05:53

0

I believe you should provide a constructor that takes a Context and AttributeSet as parameters

public yourClass(Context context, AttributeSet attrs){
   super(context,attrs);
  // Your implementation
}

You can refer to this link http://developer.android.com/training/custom-views/create-view.html

answered Dec 09 '14 at 05:53

ArsenalFC

176
1
1
6

Sorry if this sounds like a dumb question but what exactly AttributeSet do? – R_mex Dec 09 '14 at 06:17
Here are a few links that might be helpful http://developer.android.com/reference/android/util/AttributeSet.html http://javatechig.com/android/creating-custom-views-in-android-tutorial http://www.vogella.com/tutorials/AndroidCustomViews/article.html http://stackoverflow.com/questions/8302229/accessing-attrs-in-attributeset-for-custom-components – ArsenalFC Dec 09 '14 at 06:26

score 0 · Answer 2 · answered Dec 09 '14 at 05:56

Try to define constructor in Custom View like :

    public FirmaDigital(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }

    public FirmaDigital(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public FirmaDigital(Context context) {
        super(context);
        init();
    }

    public void init(){
        mPath = new Path();
        mBitmapPaint = new Paint(Paint.DITHER_FLAG);

        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        mPaint.setDither(true);
        mPaint.setColor(0xFF000000);
        mPaint.setStyle(Paint.Style.STROKE);
        mPaint.setStrokeJoin(Paint.Join.ROUND);
        mPaint.setStrokeCap(Paint.Cap.ROUND);
        mPaint.setStrokeWidth(3);
    }

Thanks for the quick response, but this didnt fix the error. — R_mex, Dec 09 '14 at 06:14

Android Studio: Error when creating signed apk

2 Answers2