Develop Reference

android canvas draw text in the triangle

In this Image I want text to totally be in the triangle with CYAN color.
I have created my own ImageView:
public class BookImageView extends android.support.v7.widget.AppCompatImageView {
private static final Float DISCOUNT_SIDE_SIZE = 0.33333F;
private Bitmap bitmap;
private Paint drawPaint = new Paint();
private Paint trianglePaint = new Paint();
{
trianglePaint.setColor(Constants.DISCOUNT_COLOR);
trianglePaint.setStyle(Paint.Style.FILL);
trianglePaint.setShadowLayer(10.0f, 10.0f, 10.0f, Color.parseColor("#7f000000"));
trianglePaint.setAntiAlias(true);
drawPaint.setColor(Color.BLACK);
drawPaint.setTypeface(Typeface.create(Typeface.DEFAULT, Typeface.BOLD));
drawPaint.setShadowLayer(1f, 0f, 1f, Color.BLACK);
}
// Constractors ...
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (bitmap != null) {
Bitmap tempBitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.RGB_565);
Canvas tempCanvas = new Canvas(tempBitmap);
tempCanvas.drawBitmap(bitmap, 0, 0, null);
Path path = new Path();
path.setFillType(Path.FillType.EVEN_ODD);
float size = bitmap.getWidth() * DISCOUNT_SIDE_SIZE;
path.lineTo(size, 0);
path.lineTo(0, size);
path.lineTo(0, 0);
path.close();
tempCanvas.drawPath(path, trianglePaint);
float scale = getResources().getDisplayMetrics().density;
drawPaint.setTextSize((int) (14 * scale));
Rect textBounds = new Rect();
drawPaint.getTextBounds("50%", 0, "50%".length(), textBounds);
int x = (int) (size / 2) - textBounds.width() / 2;
int y = (int) (size / 2) - textBounds.height() / 2;
tempCanvas.save();
tempCanvas.rotate(-45, x, y);
tempCanvas.drawText("50%", x, y, drawPaint);
tempCanvas.restore();
setImageDrawable(new BitmapDrawable(getContext().getResources(), tempBitmap));
}
}
#Override
public void setImageBitmap(Bitmap bitmap) {
this.bitmap = bitmap;
invalidate();
}
}
what can I do to solve this problem ?

You can try something like this
1) Measure the width of your text
Use measureText
2) From the point you are drawing calculate the width remaining to draw
3) Now depending on the use case you can curtail the length of text or scale the text as needed
int textWidthRequired = (int) drawPaint.measureText(textToDraw);
int widthRemainingToDraw = totalWidth/2 - textDrawX;
if(textWidthRequired > widthRemainingToDraw){
//handling
}
// draw text
tempCanvas.drawText(textToDraw,textDrawX, textDrawY, drawPaint);

Depending on how high up you want the text to be, you can use properties of similar triangles to first determine the maximum width of the text. In your case, size = the triangle's base, and size = the triangle's height/altitude. Let's define two variables:
Correction: The altitude won't be equal to the base. You'd need to calculate the altitude in order to use the below solution.
float triangleBase = size; // triangle base
float triangleAltitude = size; // Calculate this.
Let's say we want the text to be halfway up the center of the triangle:
float textYHeight = triangleHeight/2;
We figure out the width of the triangle at this point by using the following formula since the sides of similar triangles are proportional:
baseOfTriangleA/baseOfTriangleB = altitudeOfTriangleA/altitudeOfTriangleB;
float triangleWidthAtTextYLocation = (textYHeight * triangleBase)/triangleAltitude;
Now that we know what the width of the triangle is at this location, we can just iterate through different text scales until the text width is less than the value triangleWidthAtTextYlocation.
float scale = getResources().getDisplayMetrics().density;
int scaleFactor = 0;
drawPaint.setTextSize((int) (scaleFactor * scale));
Rect textBounds = new Rect();
drawPaint.getTextBounds("50%", 0, "50%".length(), textBounds);
while(textBounds.length < triangleWidthAtTextYLocation){
// Re-measure the text until it exceeds the width
scaleFactor++;
drawPaint.setTextSize((int) (scaleFactor * scale));
drawPaint.getTextBounds("50%", 0, "50%".length(), textBounds);
}
// Once we know the scaleFactor that puts it over the width of the triangle
// at that location, we reduce it by 1 to be just under that width:
scaleFactor = Maths.abs(scaleFactor - 1);
// final text size:
drawPaint.setTextSize((int) (scaleFactor * scale));

Android - Any library for adding repost label to bitmap

I have been trying to make a photo sharing app, with the ability to add your image and name to the image. I have been messing with Canvas for the whole day, but couldn't get good results. I was able to draw the name and bitmap, but they didn't look so good.
That's why I am here asking about is there any library or piece of code that could help me in making something similar to [this][1]. I wasn't able to find any thing for it.
EDIT: Sorry for not adding my own code
Here is my code from my latest try
public void AddText(Position2D pos){
//Position2D is an enum having the 4 corners of the image
bmWorking= bmOriginal.copy(Bitmap.Config.ARGB_8888,true);
Canvas canvas = new Canvas(bmWorking);
Paint paint = new Paint();
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.FILL);
Paint textPaint = new Paint();
textPaint.setColor(Color.BLACK);
float width = (35f/100f) * bmWorking.getWidth();
float height = (width/16f) * 3;
textPaint.setTextSize(height - 4); //I wanted to have some space (margin) above and below the text
textPaint.setTextAlign(Paint.Align.LEFT);
float [] coords = getPositionCoords(pos, width, height); //getPositionCoords returns a float array with the Left,Top,Right,Bottom position calculated based on the width and height
canvas.drawRect(coords[0],coords[1], coords[2], coords[3],paint);
username = "Haider Ali Punjabi";
canvas.drawText(username, coords[0] ,coords[3], textPaint);
bitmapView.setImageBitmap(bmWorking);
}
Here is the result
UPDATE:
#pskink gave me this code
which works nicely

if you want to customize it, then instead of solid white rectangle (like in your original code) use a Drawable and the result could be something like this:
the code:
// for int gravity: see android.view.Gravity, like Gravity.LEFT, Gravity.BOTTOM, etc
// for example:
// Bitmap out = addText(this, in, "Haider Ali Punjabi", android.R.drawable.alert_light_frame, Gravity.BOTTOM, new Point(10, 10));
public Bitmap addText(Context ctx, Bitmap in, String text, int resId, int gravity, Point pad) {
if (pad == null) pad = new Point();
Bitmap out = in.copy(Bitmap.Config.ARGB_8888, true);
Canvas canvas = new Canvas(out);
Paint textPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
textPaint.setColor(Color.BLACK);
textPaint.setTextAlign(Paint.Align.LEFT);
// textPaint.setTextSize(128);
Rect inBounds = new Rect();
textPaint.getTextBounds(text, 0, text.length(), inBounds);
float scale = out.getWidth() * 0.35f / inBounds.width();
Rect container = new Rect(0, 0, out.getWidth(), out.getHeight());
Rect outBounds = new Rect();
int w = (int) (inBounds.width() * scale);
int h = (int) (inBounds.height() * scale);
Gravity.apply(gravity, 2 * pad.x + w, 2 * pad.y + h, container, outBounds);
Drawable dr = ctx.getResources().getDrawable(resId);
Rect padding = new Rect();
dr.getPadding(padding);
dr.setBounds(outBounds.left - padding.left, outBounds.top - padding.top, outBounds.right + padding.right, outBounds.bottom + padding.bottom);
dr.draw(canvas);
Matrix matrix = new Matrix();
RectF src = new RectF(inBounds);
RectF dst = new RectF(outBounds);
dst.inset(pad.x, pad.y);
matrix.setRectToRect(src, dst, Matrix.ScaleToFit.CENTER);
canvas.concat(matrix);
canvas.drawText(text, 0, 0, textPaint);
return out;
}

Canvas draw rectangle android

public static Bitmap getCircularBitmapWithWhiteBorder(Bitmap bitmap,
int borderWidth) {
if (bitmap == null || bitmap.isRecycled()) {
return null;
}
final int width = bitmap.getWidth() + borderWidth;
final int height = bitmap.getHeight() + borderWidth;
Bitmap canvasBitmap = Bitmap.createBitmap(width*2, height, Bitmap.Config.ARGB_8888);
BitmapShader shader = new BitmapShader(bitmap, TileMode.CLAMP, TileMode.CLAMP);
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(shader);
Canvas canvas = new Canvas(canvasBitmap);
float radius = width > height ? ((float) height) / 2f : ((float) width) / 2f;
canvas.drawCircle(width / 2, height / 2, radius, paint);
paint.setShader(null);
paint.setStyle(Paint.Style.STROKE);
paint.setColor(Color.WHITE);
paint.setStrokeWidth(borderWidth);
canvas.drawCircle(width / 2, height / 2, radius - borderWidth / 2, paint);
return canvasBitmap;
}
I have circular image, i want to attach next to circular image sort of a rectangle..similar to his
this is a circle, next to it there is a rectangle attached. how can I do this?

You could draw your Rectangle more or less like this:
canvas.drawRect(width/2 + radius, height/2 - radius, width , height, paint);
just adjust the parameters for positioning it correctly if needed

Rotate text when drawing it on a bitmap

I want to rotate my text by 180 degrees when drawing it on a bitmap. The bitmap itself could also be rotated as there is nothing else drawn on it other than the text. It isn't clear to me though what I should be using in the code below to rotate the text: ImageView, canvas, paint, bitmap???
ImageView ivImage = (ImageView)findViewById(R.id.ivImage);
DisplayMetrics metrics = getResources().getDisplayMetrics();
int width = metrics.widthPixels;
int height = metrics.heightPixels;
Bitmap.Config conf = Bitmap.Config.ARGB_8888;
Bitmap bitmap = Bitmap.createBitmap(width, height, conf);
Canvas canvas = new Canvas(bitmap);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setColor(Color.RED);
paint.setTextSize((int) (200 * 1));
// draw text to the Canvas center
Rect bounds = new Rect();
paint.setTextAlign(Align.CENTER);
String text = "HELP";
paint.getTextBounds(text, 0, text.length(), bounds);
int x = bitmap.getWidth() / 2; // (bitmap.getWidth() - bounds.width())/2;
int y = bitmap.getHeight() / 2; // (bitmap.getHeight() + bounds.height())/2;
canvas.drawText(text, x * 1, y * 1, paint);
ivImage.setImageBitmap(bitmap);

I hope this could help. This is how i did when creating a clock
// Save canvas in current state
canvas.save();
// Rotate canvas around center and draw
canvas.rotate(degrees, canvasWidth/2, canvasHeigth/2);
canvas.drawText(text, x, y, paint)
// Restore canvas, rotates it back to original
canvas.restore();

Android - Converting string to image

I need to read the text/string from database and convert them into images. I tried the following code but I am getting only blank images. Please help
public Bitmap textAsBitmap(String text, float largest, int textColor) {
Paint paint = new Paint();
paint.setStyle(Paint.Style.FILL);
paint.setColor(textColor);
// int width = (int) (paint.measureText(text) + 0.5f); // round
paint.setAntiAlias(true);
paint.setTypeface(Typeface.MONOSPACE);
paint.setTextSize(16);
int width = 400;
// float baseline = (int) (paint.ascent() + 0.5f) + 3f;
// int height = (int) ((baseline + paint.descent() + 0.5f) + 3);
int height = 400;
Bitmap image = Bitmap.createBitmap(width, height,
Bitmap.Config.RGB_565);
Canvas canvas = new Canvas(image);
canvas.drawText(text, 0, 5, paint);
return image;
}

I haven't tried this, but do you perhaps need to first fill your bitmap with a colour that contrasts with textColor? This would certainly seem like an important thing to do in any case -- the documentation for createBitmap() does not specify the initial content of the bitmap, so it could theoretically be anything, and may change in future versions of the system.