how to set backgroundColor to a surfaceview in android?

Question

i am using a surface view to draw interactive piechart. here is my code which will looks like all surface view examples.

class PieChart extends SurfaceView implements SurfaceHolder.Callback {

public PieChart(Context context) {
        super(context);
        // Log.i("PieChart", "PieChart : constructor");
        getHolder().addCallback(this); 
}

@Override
    public void onDraw(Canvas canvas) {
        if (hasData) {

            resetColor();
            try {
                canvas.drawColor(getResources().getColor(R.color.graphbg_color));

                graphDraw(canvas);
            } catch (ValicException ex) {

            }

        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width,
            int height) {

        Log.i("PieChart", "surfaceChanged");

    }

    public int callCount = 0;

    @Override
    public void surfaceCreated(SurfaceHolder holder) {

            try {
                // Log.i("PieChart", "surfaceCreated");
                mChartThread = new ChartThread(getHolder(), this);
                mChartThread.setRunning(true);

                if (!mChartThread.isAlive()) {
                    mChartThread.start();
                }

                Rect mFrame = holder.getSurfaceFrame();

                mOvalF = new RectF(0, 0, mFrame.right, mFrame.right);

            } catch (Exception e) {
                // No error message required
            }

    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        // Log.i("PieChart", "surfaceDestroyed");
        boolean retry = true;
        callCount = 0;
        mChartThread.setRunning(false);
        while (retry) {
            try {
                mChartThread.join();
                retry = false;
            } catch (InterruptedException e) {
                // No error message required
            }
        }
    }
}

class ChartThread extends Thread {

    private SurfaceHolder mSurfaceHolder;
    private PieChart mPieChart;
    private boolean mRefresh = false;

    public ChartThread(SurfaceHolder surfaceHolder, PieChart pieChart) {
        // Log.i("ChartThread", "ChartThread");
        mSurfaceHolder = surfaceHolder;
        mPieChart = pieChart;
    }

    public void setRunning(boolean Refresh) {
        // Log.i("ChartThread", "setRunning : " + Refresh);
        mRefresh = Refresh;
    }

    @Override
    public void run() {
        Canvas c;
        // Log.i("ChartThread", "run : " + mRefresh);
        while (mRefresh) {
            c = null;
            try {
                c = mSurfaceHolder.lockCanvas(null);
            //  c.drawColor(0xFFebf3f5);
                synchronized (mSurfaceHolder) {

                    mPieChart.onDraw(c);

                }
            } catch (Exception ex) {

            } finally {
                // do this in a finally so that if an exception is thrown
                // during the above, we don't leave the Surface in an
                // inconsistent state
                if (c != null) {
                    mSurfaceHolder.unlockCanvasAndPost(c);
                }
            }
        }
    }
}

with this i am able to draw pie charts successfully. but here the issue is "before loading pie chart black rectangle is visible for a second which is surfaceview's default back ground". so I want to set background color for surface view to avoid the black rectangle.

The following is the changed code for drawing background color to surface view.

 public PieChart(Context context) {
            super(context);
            // Log.i("PieChart", "PieChart : constructor");
            getHolder().addCallback(this); 
            setBackgroundColor(getResources().getColor(R.color.graphbg_color));
    }


@Override
    public void onDraw(Canvas canvas) {
        if (hasData) {
             setBackgroundColor(getResources().getColor(R.color.graphbg_color));
            resetColor();
            try {
        canvas.drawColor(getResources().getColor(R.color.graphbg_color));

                graphDraw(canvas);
            } catch (ValicException ex) {

            }

        }
    }

with these changes, black rectangle issue is resolved. but piechart is not refreshing properly. can someone help me to resolve any of these two issues.

Solution

class PieChart extends SurfaceView implements SurfaceHolder.Callback {

private int backGroundColor = Color.BLACK;

public PieChart(Context context,int backGroundColor) {
    super(context);
    setBackGroundColor(backGroundColor);
    // Log.i("PieChart", "PieChart : constructor");
    getHolder().addCallback(this); 
}

public void setBackGroundColor(int color){
    this.backGroundColor = color;
}

@Override
public void onDraw(Canvas canvas) {

            Paint paint = new Paint();
            paint.setStyle(Paint.Style.FILL_AND_STROKE);
            paint.setStrokeWidth(3);
            paint.setAntiAlias(true);
            paint.setColor(backGroundColor);
    canvas.drawRect(0, 0, this.getWidth(), this.getHeight(), paint);

    if (hasData) {

        resetColor();
        try {

            canvas.drawColor(getResources().getColor(R.color.graphbg_color));

            graphDraw(canvas);
        } catch (ValicException ex) {

        }

    }
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
        int height) {

    Log.i("PieChart", "surfaceChanged");

}

public int callCount = 0;

@Override
public void surfaceCreated(SurfaceHolder holder) {

        try {
            // Log.i("PieChart", "surfaceCreated");
            mChartThread = new ChartThread(getHolder(), this);
            mChartThread.setRunning(true);

            if (!mChartThread.isAlive()) {
                mChartThread.start();
            }

            Rect mFrame = holder.getSurfaceFrame();

            mOvalF = new RectF(0, 0, mFrame.right, mFrame.right);

        } catch (Exception e) {
            // No error message required
        }

}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
    // Log.i("PieChart", "surfaceDestroyed");
    boolean retry = true;
    callCount = 0;
    mChartThread.setRunning(false);
    while (retry) {
        try {
            mChartThread.join();
            retry = false;
        } catch (InterruptedException e) {
            // No error message required
        }
    }
}
}

class ChartThread extends Thread {

private SurfaceHolder mSurfaceHolder;
private PieChart mPieChart;
private boolean mRefresh = false;

public ChartThread(SurfaceHolder surfaceHolder, PieChart pieChart) {
    // Log.i("ChartThread", "ChartThread");
    mSurfaceHolder = surfaceHolder;
    mPieChart = pieChart;
}

public void setRunning(boolean Refresh) {
    // Log.i("ChartThread", "setRunning : " + Refresh);
    mRefresh = Refresh;
}

@Override
public void run() {
    Canvas c;
    // Log.i("ChartThread", "run : " + mRefresh);
    while (mRefresh) {
        c = null;
        try {
            c = mSurfaceHolder.lockCanvas(null);
        //  c.drawColor(0xFFebf3f5);
            synchronized (mSurfaceHolder) {

                mPieChart.onDraw(c);

            }
        } catch (Exception ex) {

        } finally {
            // do this in a finally so that if an exception is thrown
            // during the above, we don't leave the Surface in an
            // inconsistent state
            if (c != null) {
                mSurfaceHolder.unlockCanvasAndPost(c);
            }
        }
    }
}
}

and in yout class client you can use the setBackGroundColor(your color) ;)