Android color picker to be included in the activity
I would like to include a color picker in my paint program. So anyone here has already done something like this please give me some tutorials or piece of code to get me started. I really need to get the whole idea of adding this. I already have set up the canvas for the drawing so I'd like to add the color picker to it. Any ideas are welcome. Thanks.
Answer
Your class should implement ColorPickerDialog.OnColorChangedListener
public class MainActivity implements ColorPickerDialog.OnColorChangedListener
{
private Paint mPaint;
mPaint = new Paint();
// on button click
new ColorPickerDialog(this, this, mPaint.getColor()).show();
}
ColorPicker Dialog
public class ColorPickerDialog extends Dialog {
public interface OnColorChangedListener {
void colorChanged(int color);
}
private OnColorChangedListener mListener;
private int mInitialColor;
private static class ColorPickerView extends View {
private Paint mPaint;
private Paint mCenterPaint;
private final int[] mColors;
private OnColorChangedListener mListener;
ColorPickerView(Context c, OnColorChangedListener l, int color) {
super(c);
mListener = l;
mColors = new int[] {
0xFFFF0000, 0xFFFF00FF, 0xFF0000FF, 0xFF00FFFF, 0xFF00FF00,
0xFFFFFF00, 0xFFFF0000
};
Shader s = new SweepGradient(0, 0, mColors, null);
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setShader(s);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeWidth(32);
mCenterPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mCenterPaint.setColor(color);
mCenterPaint.setStrokeWidth(5);
}
private boolean mTrackingCenter;
private boolean mHighlightCenter;
@Override
protected void onDraw(Canvas canvas) {
float r = CENTER_X - mPaint.getStrokeWidth()*0.5f;
canvas.translate(CENTER_X, CENTER_X);
canvas.drawOval(new RectF(-r, -r, r, r), mPaint);
canvas.drawCircle(0, 0, CENTER_RADIUS, mCenterPaint);
if (mTrackingCenter) {
int c = mCenterPaint.getColor();
mCenterPaint.setStyle(Paint.Style.STROKE);
if (mHighlightCenter) {
mCenterPaint.setAlpha(0xFF);
} else {
mCenterPaint.setAlpha(0x80);
}
canvas.drawCircle(0, 0,
CENTER_RADIUS + mCenterPaint.getStrokeWidth(),
mCenterPaint);
mCenterPaint.setStyle(Paint.Style.FILL);
mCenterPaint.setColor(c);
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
setMeasuredDimension(CENTER_X*2, CENTER_Y*2);
}
private static final int CENTER_X = 100;
private static final int CENTER_Y = 100;
private static final int CENTER_RADIUS = 32;
private int floatToByte(float x) {
int n = java.lang.Math.round(x);
return n;
}
private int pinToByte(int n) {
if (n < 0) {
n = 0;
} else if (n > 255) {
n = 255;
}
return n;
}
private int ave(int s, int d, float p) {
return s + java.lang.Math.round(p * (d - s));
}
private int interpColor(int colors[], float unit) {
if (unit <= 0) {
return colors[0];
}
if (unit >= 1) {
return colors[colors.length - 1];
}
float p = unit * (colors.length - 1);
int i = (int)p;
p -= i;
// now p is just the fractional part [0...1) and i is the index
int c0 = colors[i];
int c1 = colors[i+1];
int a = ave(Color.alpha(c0), Color.alpha(c1), p);
int r = ave(Color.red(c0), Color.red(c1), p);
int g = ave(Color.green(c0), Color.green(c1), p);
int b = ave(Color.blue(c0), Color.blue(c1), p);
return Color.argb(a, r, g, b);
}
private int rotateColor(int color, float rad) {
float deg = rad * 180 / 3.1415927f;
int r = Color.red(color);
int g = Color.green(color);
int b = Color.blue(color);
ColorMatrix cm = new ColorMatrix();
ColorMatrix tmp = new ColorMatrix();
cm.setRGB2YUV();
tmp.setRotate(0, deg);
cm.postConcat(tmp);
tmp.setYUV2RGB();
cm.postConcat(tmp);
final float[] a = cm.getArray();
int ir = floatToByte(a[0] * r + a[1] * g + a[2] * b);
int ig = floatToByte(a[5] * r + a[6] * g + a[7] * b);
int ib = floatToByte(a[10] * r + a[11] * g + a[12] * b);
return Color.argb(Color.alpha(color), pinToByte(ir),
pinToByte(ig), pinToByte(ib));
}
private static final float PI = 3.1415926f;
@Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX() - CENTER_X;
float y = event.getY() - CENTER_Y;
boolean inCenter = java.lang.Math.sqrt(x*x + y*y) <= CENTER_RADIUS;
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
mTrackingCenter = inCenter;
if (inCenter) {
mHighlightCenter = true;
invalidate();
break;
}
case MotionEvent.ACTION_MOVE:
if (mTrackingCenter) {
if (mHighlightCenter != inCenter) {
mHighlightCenter = inCenter;
invalidate();
}
} else {
float angle = (float)java.lang.Math.atan2(y, x);
// need to turn angle [-PI ... PI] into unit [0....1]
float unit = angle/(2*PI);
if (unit < 0) {
unit += 1;
}
mCenterPaint.setColor(interpColor(mColors, unit));
invalidate();
}
break;
case MotionEvent.ACTION_UP:
if (mTrackingCenter) {
if (inCenter) {
mListener.colorChanged(mCenterPaint.getColor());
}
mTrackingCenter = false; // so we draw w/o halo
invalidate();
}
break;
}
return true;
}
}
public ColorPickerDialog(Context context,
OnColorChangedListener listener,
int initialColor) {
super(context);
mListener = listener;
mInitialColor = initialColor;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
OnColorChangedListener l = new OnColorChangedListener() {
public void colorChanged(int color) {
mListener.colorChanged(color);
dismiss();
}
};
setContentView(new ColorPickerView(getContext(), l, mInitialColor));
setTitle("Pick a Color");
}
You have to choose the color and click the center circle to pick the color. Set the color to your paint object and use the same to draw.
Snap shot
Edit 2:
Source code can be found at https://code.google.com/p/android-color-picker/
Another ColorPickerDialog
public class ColorPickerDialog extends AlertDialog implements
ColorPickerView.OnColorChangedListener {
private ColorPickerView mColorPicker;
private ColorPanelView mOldColor;
private ColorPanelView mNewColor;
private OnColorChangedListener mListener;
public ColorPickerDialog(Context myDrawingMenuOptionEventsListener, int initialColor) {
super(myDrawingMenuOptionEventsListener);
init(initialColor);
}
private void init(int color) {
// To fight color branding.
getWindow().setFormat(PixelFormat.RGBA_8888);
setUp(color);
}
private void setUp(int color) {
LayoutInflater inflater = (LayoutInflater) getContext()
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View layout = inflater.inflate(R.layout.dialog_color_picker, null);
layout.setBackgroundColor(Color.WHITE);
setView(layout);
setTitle("Choose a Color");
// setIcon(android.R.drawable.ic_dialog_info);
mColorPicker = (ColorPickerView) layout
.findViewById(R.id.color_picker_view);
mOldColor = (ColorPanelView) layout.findViewById(R.id.old_color_panel);
mNewColor = (ColorPanelView) layout.findViewById(R.id.new_color_panel);
((LinearLayout) mOldColor.getParent()).setPadding(Math
.round(mColorPicker.getDrawingOffset()), 0, Math
.round(mColorPicker.getDrawingOffset()), 0);
mColorPicker.setOnColorChangedListener(this);
mOldColor.setColor(color);
mColorPicker.setColor(color, true);
}
@Override
public void onColorChanged(int color) {
mNewColor.setColor(color);
if (mListener != null) {
mListener.onColorChanged(color);
}
}
public void setAlphaSliderVisible(boolean visible) {
mColorPicker.setAlphaSliderVisible(visible);
}
public int getColor() {
return mColorPicker.getColor();
}
}
Usage :
final ColorPickerDialog d= new ColorPickerDialog(ActivityName.this,0xffffffff);
d.setAlphaSliderVisible(true);
d.setButton("Ok", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
mPaint.setColor(d.getColor());
}
});
d.setButton2("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
});
d.show();
Snap shot:
In the above choose the color on the right bar. You also make a choice how dark or light the color choosen should be. Click ok to set the paint to your paint object and use the same to draw. Cancel will dismiss the color picker dialog.
Edit 3:
Only change instead of clear function i have added color picker on click of clear button.
public class MainActivity extends Activity implements ColorPickerDialog.OnColorChangedListener {
DrawingView dv ;
RelativeLayout rl;
private Paint mPaint;
private MaskFilter mEmboss;
private MaskFilter mBlur;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
dv = new DrawingView(this);
setContentView(R.layout.activity_main);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(Color.GREEN);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(12);
rl = (RelativeLayout) findViewById(R.id.rl);
rl.addView(dv);
Button b = (Button) findViewById(R.id.button1);
//b.setText(R.string.France);
Button b1 = (Button) findViewById(R.id.button2);
rl.setDrawingCacheEnabled(true);
b.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
// dv.clear();
new ColorPickerDialog(MainActivity.this, MainActivity.this, mPaint.getColor()).show();
}
});
b1.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
AlertDialog.Builder editalert = new AlertDialog.Builder(MainActivity.this);
editalert.setTitle("Please Enter the name with which you want to Save");
final EditText input = new EditText(MainActivity.this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.FILL_PARENT,
LinearLayout.LayoutParams.FILL_PARENT);
input.setLayoutParams(lp);
editalert.setView(input);
editalert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
rl.setDrawingCacheEnabled(true);
String name= input.getText().toString();
Bitmap bitmap =rl.getDrawingCache();
String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/MyDraw");
myDir.mkdirs();
File file = new File (myDir, name+".png");
if (file.exists ()) file.delete ();
try
{
if(!file.exists())
{
file.createNewFile();
}
FileOutputStream ostream = new FileOutputStream(file);
bitmap.compress(CompressFormat.PNG, 10, ostream);
// System.out.println("saving......................................................"+path);
ostream.close();
rl.invalidate();
}
catch (Exception e)
{
e.printStackTrace();
}finally
{
rl.setDrawingCacheEnabled(false);
}
}
});
editalert.show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
public class DrawingView extends View {
private static final float MINP = 0.25f;
private static final float MAXP = 0.75f;
private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Paint mBitmapPaint;
Context context;
private Paint circlePaint;
private Path circlePath;
public DrawingView(Context c) {
super(c);
context=c;
mPath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
circlePaint = new Paint();
circlePath = new Path();
circlePaint.setAntiAlias(true);
circlePaint.setColor(Color.BLUE);
circlePaint.setStyle(Paint.Style.STROKE);
circlePaint.setStrokeJoin(Paint.Join.MITER);
circlePaint.setStrokeWidth(4f);
}
@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) {
super.onDraw(canvas);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mPath, mPaint);
canvas.drawPath(circlePath, circlePaint);
}
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(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;
circlePath.reset();
circlePath.addCircle(mX, mY, 30, Path.Direction.CW);
invalidate();
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
circlePath.reset();
// 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_start(x, y);
invalidate();
break;
case MotionEvent.ACTION_MOVE:
touch_move(x, y);
invalidate();
break;
case MotionEvent.ACTION_UP:
touch_up();
invalidate();
break;
}
return true;
}
}
@Override
public void colorChanged(int color) {
// TODO Auto-generated method stub
mPaint.setColor(color);
}
}
