In this example code I give a nice square in the form I want. canvas.drawRect (100, 300, 600, 800, paint); values work. But what I want is to call these values from the Activity class. So I want to send these values to the Draw class in the activity class. How can I do that ? For example, I want to send an activity class as drawRect (100,100,100,100, Color.BLUE). I do not want to write these values in the Draw class.
Draw.java
public class Draw extends View {
Paint paint;
Path path;
public Draw(Context context) {
super(context);
init();
}
public Draw(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public Draw(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
public void init(){
paint = new Paint();
paint.setColor(Color.BLACK);
paint.setStrokeWidth(10);
paint.setStyle(Paint.Style.STROKE);
}
#Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
canvas.drawRect(100, 300, 600, 800, paint);
}
}
Activity.java
constraintLayout=findViewById(R.id.constraint);
Draw draw = new Draw(this);
constraintLayout.addView(draw);
You need to make method and pass value from activity to draw class:-
Draw draw = new Draw(this,100, 300, 600, 800);
constraintLayout.addView(draw);
Draw class
public class Draw extends View {
Paint paint;
Path path;
float left;
float top;
float right;
float bottom;
public Draw(Context context,float left, float top, float right, float bottom) {
super(context);
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
init();
}
public Draw(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public Draw(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
public void init(){
paint = new Paint();
paint.setColor(Color.BLACK);
paint.setStrokeWidth(10);
paint.setStyle(Paint.Style.STROKE);
}
#Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
canvas.drawRect(left, top, right, bottom, paint);
}
}
You can create local variables for the bounds and set them using setters or init function before adding that view to a viewgroup.( constraintLayout.addView(draw) in your case
Related
I have 12 lines I've created using the following class
public class LineView extends View {
private Paint paint = new Paint();
private PointF pointA,pointB;
// private void init() {
// paint.setColor(Color.BLACK);
// }
public LineView(Context context) {
super(context);
// init();
}
public LineView(Context context, AttributeSet attrs) {
super(context, attrs);
// init();
}
public LineView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// init();
}
#SuppressLint("ResourceAsColor")
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
int color = R.color.GradientStart;
paint.setColor(color);
paint.setColor(Color.BLUE);
paint.setStrokeWidth(5);
//canvas.drawLine(x1, y1, x2, y2, paint);
canvas.drawLine(pointA.x, pointA.y, pointB.x, pointB.y, paint);
}
public void setPointA(PointF point){
pointA=point;
}
public void setPointB(PointF point){
pointB=point;
}
public void draw(){
invalidate();
requestLayout();
}
}
Instead of lines I what lines with arrows. The line with arrow will be drawn between buttons.
How can I add arrows to one end of my lines?
It would like like this when complete.
thanks
JN
I found two way for achieve your requirement.
1) To use nine patch image. I have tried to make nine patch image for you please use it
2) You can use vector image for it.
Tell me still you not getting solution.
I am trying to draw rounded corner line using canvas. Like eg:
public class MyView extends View {
Paint paint;
Path path;
public MyView(Context context) {
super(context);
init();
}
public MyView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public MyView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
paint = new Paint();
paint.setColor(Color.BLUE);
paint.setStrokeWidth(10);
paint.setStyle(Paint.Style.STROKE);
path = new Path();
path.moveTo(50, 50);
path.lineTo(50, 500);
path.lineTo(200, 500);
path.lineTo(200, 300);
path.lineTo(350, 300);
float radius = 50.0f;
CornerPathEffect cornerPathEffect =
new CornerPathEffect(radius);
paint.setPathEffect(cornerPathEffect);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawPath(path, paint);
}
}
I am able to draw corner line using paint as shown above, but not from the canvas.
I tried canvas.drawLine() and canvas.drawArc() to achieve the same result but failed to do that.
Can somebody help me to solve the issue?
Can you Give me any advice how to draw a list of rectangles?
I have a Rectangle class :
public final class Rectangle extends View {
private Rect rectangle;
private Paint paint;
public Rectangle(Context context) {
super(context);
int x = 50;
int y = 50;
int sideLength = 200;
// create a rectangle that we'll draw later
rectangle = new Rect(x, y, sideLength, sideLength);
// create the Paint and set its color
paint = new Paint();
paint.setColor(Color.GRAY);
}
#Override
protected void onDraw(Canvas canvas) {
//canvas.drawColor(Color.BLUE);
canvas.drawRect(rectangle, paint);
}
}
and a Rectangle instance on activity
setContentView(new Rectangle(this));
Here you have some example three rectangles side by side
public class Rectangles extends View {
private Paint paintBlack;
public Rectangles(Context context) {
super(context);
init();
}
public Rectangles(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public Rectangles(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
paintBlack = new Paint();
paintBlack.setColor(Color.BLACK);
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawRect(0, 0, 100, 100, paintBlack);
canvas.drawRect(105, 0, 205, 100, paintBlack);
canvas.drawRect(210, 0, 310, 100, paintBlack);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
setMeasuredDimension(500, 500);
}
}
Drawable not drawing in custom TextView. Can anyone please help me in sorting the problem out. What i was trying to build is a texview that shows progress. The below mention code is just a sample.
public class ProgressableTextview extends TextView {
Paint mPaint;
int mProgress = 70;
int maxProgress = 100;
int mRadiud = 10;
public ProgressableTextview(Context context) {
super(context);
init();
}
public ProgressableTextview(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public ProgressableTextview(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
public void init(){
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(Color.BLACK);
mPaint.setStyle(Paint.Style.FILL);
}
#Override
public void onDraw(Canvas canvas) {
canvas.drawColor(Color.GRAY);
canvas.drawRect(0, 0, (mProgress/maxProgress)*getWidth(), getMeasuredHeight(), mPaint);
canvas.save();
canvas.translate(getLeft(), 0);
super.onDraw(canvas);
canvas.restore();
}
}
Ok i figured out what was the problem, it was the mistake in drawRect function. drawRect function need to changed as :
canvas.drawRect(0, 0, ((float) mProgress/maxProgress) * getWidth(), getMeasureHeight(), mPaint);
since mProgress was a integer dividing it by integer returns zero and that was the problem.
I want to redraw a view from another method (say setProgress) in a class extending View. How can I do this.
My view class is
public class SpinView extends View {
private Paint paint;
private Context context;
private Canvas canvas;
private RectF arcOval;
public SpinView(Context context) {
super(context);
this.context = context;
}
public SpinView(Context context, AttributeSet attrs) {
super(context, attrs, 0);
this.context = context;
}
public SpinView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
this.context = context;
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
this.canvas = canvas;
Display d = ((WindowManager)context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int width = d.getWidth();
int height = d.getHeight();
arcOval = new RectF((width/2-50), (height/2-50), (width/2+50), (height/2+50));
// RectF arcOval = new RectF(200, 200, 300, 300);
paint = new Paint();
paint.setColor(Color.BLUE);
paint.setStrokeWidth(10);
paint.setAntiAlias(true);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStyle(Paint.Style.STROKE);
canvas.drawArc(arcOval, 270f, 360, false, paint);
}
protected void setProgress(float angle){
paint = new Paint();
paint.setColor(Color.YELLOW);
paint.setStrokeWidth(10);
paint.setAntiAlias(true);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStyle(Paint.Style.STROKE);
canvas.drawArc(arcOval, 270f, angle, false, paint);
}
}
All I want is to draw a circular arc of yellow color over the initially created arc of Blue color. Any help?
You can use invalidate() method to call ondraw again