Question

I am new comer to android but not to java. I have been designing UI in android through XML file, in that page i have 3 linear Layouts, in my top layout(first LinearLayout) i have kept some image and in the last layout i have kept some buttons,now i need to place a circle(of red color) in my center layout using canvas,i have written a separate class that extends View where in onDraw(Canvas canvas) ,i have drawn a circle.

package com.project.TargetTrackr3;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.view.View;

public class DrawCanvasCircle extends View{
    public DrawCanvasCircle(Context mContext) {
        super(mContext);
    }
    public void onDraw(Canvas canvas) {
        Paint paint = new Paint();
        paint.setStyle(Paint.Style.FILL);
        canvas.drawColor(Color.WHITE);
        paint.setColor(Color.BLUE);
        canvas.drawCircle(20, 20, 15, paint);
    }

}

Now i have to bring this canvas to the second layout,my main.xml is shown below

package com.project.TargetTrackr3;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.ColorFilter;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.view.View;
import android.widget.LinearLayout;
public class TargetTrackr3Activity extends Activity {
    /** Called when the activity is first created. */
      protected LinearLayout ll;
      DrawCanvasCircle c;
      public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main1); //layouting file 
        ll = (LinearLayout) findViewById(R.id.LinearLayout_DrawCircle);//This is where i have to bring the canvas
        c = new DrawCanvasCircle(this);
           ...................................
           ................................



    }
}

Answer 1

Here is what I did to include your view.

Start with adding a new layout to your xml file, then you can retrieve that, and then you can add to it like this:

    DrawCanvasCircle pcc = new DrawCanvasCircle (this);
    Bitmap result = Bitmap.createBitmap(25, 25, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(result);
    pcc.draw(canvas);
    pcc.setLayoutParams(new LayoutParams(25, 25));
    mControls.addView(pcc);

In this example mControls is a layout that is added to the main activity layout.