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Why Bitmap size change in different screen?

I Convert Text to Bitmap with this method:
private Bitmap textToBitmap(String text)
{
Bitmap myBitmap = Bitmap.createBitmap(400, 50, Bitmap.Config.ARGB_4444);
Canvas myCanvas = new Canvas(myBitmap);
Paint paint = new Paint();
Typeface clock = Typeface.createFromAsset(context.getAssets(),"fonts/myfont.ttf");
paint.setAntiAlias(true);
paint.setSubpixelText(true);
paint.setTypeface(clock);
paint.setStyle(Paint.Style.FILL);
paint.setColor(Color.WHITE );
paint.setTextSize(38);
paint.setTextAlign(Paint.Align.RIGHT);
myCanvas.drawText(text, 400, 30, paint);
return myBitmap;
}
But in some of phone my bitmap is very small and in other its very Big
why that Happen?

Bitmap myBitmap = Bitmap.createBitmap(400, 50, Bitmap.Config.ARGB_4444);//its unit is px, practical size of 1 px is different in various device.
You should resize bitmap according to device scaledDensity, here is a good solution

Android: How to make a percentage of a bitmap black and white, retaining color in the rest?

I've got a bitmap displayed in an ImageView, and I want to be able to make a certain percentage of the image black and white, and have the other part retain it's color. For example, if 60% is the target percentage, the image would look like this: . Thanks.

I've got a bitmap displayed in an ImageView, and I want to be able to
make a certain percentage of the image black and white, and have the
other part retain it's color. For example, if 60% is the target
percentage.
It seems (from your image) you mean monochrome (i.e. greyscale), not black and white.
Something like this should do it (tested o.k.):
void doIt(ImageView image)
{
//get bitmap from your ImageView (image)
Bitmap originalBitmap = ((BitmapDrawable)image.getDrawable()).getBitmap();
int height = originalBitmap.getHeight();
int fortyPercentHeight = (int) Math.floor(height * 40.0 / 100.0);
//create a bitmap of the top 40% of image height that we will make black and white
Bitmap croppedBitmap = Bitmap.createBitmap(originalBitmap, 0, 0, originalBitmap.getWidth() , fortyPercentHeight );
//make it monochrome
Bitmap blackAndWhiteBitmap = monoChrome(croppedBitmap);
//copy the monochrome bmp (blackAndWhiteBitmap) to the original bmp (originalBitmap)
originalBitmap = overlay(originalBitmap, blackAndWhiteBitmap);
//set imageview to new bitmap
image.setImageBitmap(originalBitmap );
}
Bitmap monoChrome(Bitmap bitmap)
{
Bitmap bmpMonochrome = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bmpMonochrome);
ColorMatrix ma = new ColorMatrix();
ma.setSaturation(0);
Paint paint = new Paint();
paint.setColorFilter(new ColorMatrixColorFilter(ma));
canvas.drawBitmap(bitmap, 0, 0, paint);
return bmpMonochrome;
}
Bitmap overlay(Bitmap bmp1, Bitmap bmp2)
{
Bitmap bmp3 = bmp1.copy(Bitmap.Config.ARGB_8888,true);//mutable copy
Canvas canvas = new Canvas(bmp3 );
canvas.drawBitmap(bmp2, new Matrix(), null);
return bmp3 ;
}

Draw in a canvas and save it to a larger image

I have a requirement, like drawing something in canvas and saving it to a larger image. As of now whatever I draw inside onDraw() method and save, it gives device provided image/canvas size, say something around 538(w)/852(h). I need image of almost double size, around 1000(w)/1500(h) without losing resolution. Any sample code, reference link would help definitely. Thanks in advance.

One way is to create Bitmap of desired size and draw on it using canvas:
int w = 1000, h = 1500;
Bitmap.Config conf = Bitmap.Config.ARGB_8888;
Bitmap bmp = Bitmap.createBitmap(w, h, conf);
Canvas canvas = new Canvas(bmp);
Finally you will have you bmp with your drawing and necessary dimentions.
EDIT::
#Override
protected void onDraw(Canvas canvas) {
int w = 1000, h = 1500;
Bitmap.Config conf = Bitmap.Config.ARGB_8888;
Bitmap bmp = Bitmap.createBitmap(w, h, conf);
Canvas mycanvas = new Canvas(bmp);
super.onDraw(mycanvas);
...
}

First get bitmap of your view using the function getDrawingCache(), then scale the bitmap as per your requirements.
view.buildDrawingCache();
Bitmap bitmap = view.getDrawingCache();
//bitmap = bitmap.createScaledBitmap(..as your requirements..);
EDIT
You are saying that you want image in higher quality. You can't simply get a higher quality image from a lower quality image. However you can apply bitmap filtering to get slightly better quality.
Bitmap bitmap = getDrawingCache();
Bitmap output = Bitmap.createBitmap(/*width, height, bla bla bla*/);
Canvas canvas = new Canvas(output);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);
Rect srcRect = new Rect(0,0,bitmap.getWidth(), bitmap.getHeight());
Rect destRect = new Rect(0,0,output.getWidth(), output.getHeight());
canvas.drawBitmap(bitmap, srcRect, destRect, paint);

How to convert the view into bitmap without adding into the UI in Android

I am using View in android and I need to convert this to Bitmap without adding this into the activity.
view.setDrawingCacheEnabled(true);
Bitmap bitmap= view.getDrawingCache();
It returns bitmap as null.
Also I have tried the method view.buildDrawingCache() but still getDrawingCache() return null.
Thanks in advance.

First you need to create empty bitmap and get canvas from it.
use below code for this
int w = WIDTH_PX, h = HEIGHT_PX;
Bitmap.Config conf = Bitmap.Config.ARGB_8888; // see other conf types
Bitmap bmp = Bitmap.createBitmap(w, h, conf); // this creates a MUTABLE bitmap
Canvas canvas = new Canvas(bmp);
Now you need to draw you view in this bitmap.
use below code for this
LinearLayout layout = new LinearLayout(getContext());
TextView textView = new TextView(getContext());
int padding = 4;
textView.setPadding(padding, padding, padding, padding);
textView.setVisibility(View.VISIBLE);
textView.setText("Hello how are you");
layout.addView(textView);
textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 10);
layout.measure(canvas.getWidth(), canvas.getHeight());
layout.layout(0, 0, canvas.getWidth(), canvas.getHeight());
layout.draw(canvas);
now your view is converted into the bitmap (bmp).

How to convert byteArray into bitmap image to show in an imageview in Android?

I have the following code for this purpose in my app but it does nothing, and halts the application:
bmImage.setImageBitmap(BitmapFactory.decodeByteArray(byteImage2, 0, byteImage2.length));

Try like this
Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
ImageView image = (ImageView) findViewById(R.id.imageView1);
image.setImageBitmap(bmp);

Then I suppose you draw the image too like this:
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);
canvas.drawBitmap(bmImage, 0, 0, paint);

use below line to convert bytes into Bitmap, it is working for me.
Bitmap bmp = BitmapFactory.decodeByteArray(imageData, 0, imageData.length);
you need to put above line outside of loop, as it takes Bytes Array and convert into Bitmap.
P.S. :- here imageData is bytes array of Image

Try this :
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.bg);
ByteArrayOutputStream blob = new ByteArrayOutputStream();
bitmap.compress(CompressFormat.PNG, 95, blob);
byte[] bitmapdata = blob.toByteArray();
Bitmap bmp = BitmapFactory.decodeByteArray(bitmapdata , 0, bitmapdata .length);
ImageView image = (ImageView) findViewById(R.id.ivPhoto);
image.setImageBitmap(bmp);