How to convert code from C + + to Java for Android?

Question

0.00/5 (No votes)

See more:

I have code in C + + that works and I would like to add it to my program on Android.

C++

extern bool rysuj;
extern bool kwadrat;
bool rys=false;
int x1, y1;
int x2, y2;
TChild *Child;

Graphics::TBitmap* bitmap = new Graphics::TBitmap;
TCanvas* dtCanvas = new TCanvas;
HWND hOkno;
RECT rcOkno;
unsigned uWidth;
unsigned uHeight;

FormMouseDown(int X, int Y)
{

   	bitmap->Width=uWidth;
   	bitmap->Height=uHeight;
	TRect src= Canvas->ClipRect;
  	bitmap->Canvas->CopyRect(src,Canvas,src);

   	if (kwadrat)
   	{
     		x1=X;
      		y1=Y;
   	}
   	rys=true;

}
FormMouseMove(int X, int Y)
{
   	if (rys && kwadrat)
   	{
        	Canvas->Draw(0,0, bitmap);
        	Canvas->Rectangle(x1, y1, X, Y);
   	}

}

FormMouseUp(int X, int Y)
{
        bitmap->Width=uWidth;
        bitmap->Height=uHeight;
        TRect src= Canvas->ClipRect;
        bitmap->Canvas->CopyRect(src,Canvas,src);

   	rys=false;


}
FormPaint(TObject *Sender)
{
        Canvas->Draw(0,0, bitmap);
}

Please to quickly response. I would be very grateful :D

Posted 17-Oct-12 21:26pm

Dragy001

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Mukesh_Chauhan · Answer 1 · 2012-10-17T21:32:00

You don't "convert C++ file to java style". You need to create a JNI wrapper around your existing C++ code. This JNI wrapper is actually C++ code that can be called by Java.

By wrapper I mean that you shouldn't have to modify your existing C++ code base. This wrapper, or better said this binding should generally be very thin. The wrapper code is only meant to expose existing functionalities, not to implement them. It is better to leave the implementation in the (portable) C++ code base.

If the code base isn't too large, then I recommend that you write this wrapper by hand, as explained in The JavaTM Native Interface Programmer's Guide and Specification

Now, if you are trying to bind a large library, it may be problematic. So, in regard to tools, I haven't used that, but have a look at SWIG, and the relevant SWIG Java documentation.

According to the homepage description, it's what you're asking for:

SWIG is typically used to parse C/C++ interfaces and generate the 'glue code' required for [Java, Python, PHP, ...] to call into the C/C++ code.

javah can be useful in certain cases, but it's not what you ask for. It extracts JNI boiler plate code out of native declarations found in Java classes. Regarding javac, it's the Java compiler, that's irrelevant.

Dragy001 · Answer 2 · 2012-10-17T21:45:00

Java

@Override
        public boolean onTouchEvent(MotionEvent event) 
        {
            float x = event.getX();
            float y = event.getY();
            switch (event.getAction()) 
            {
                case MotionEvent.ACTION_DOWN:
                    if (kwadrat) {
                    	rect = new Rect();
                        touch_start(x, y);
                		invalidate();
					}

                    tryb_rys = true;
                    break;
                case MotionEvent.ACTION_MOVE:

                    if (kwadrat && tryb_rys) {
                    	rect.set((int)mX, (int)mY, (int)event.getX(), (int)event.getY());
                    	mCanvas.drawRect(rect, mPaint);
                		invalidate();

                	break;
                case MotionEvent.ACTION_UP:

                    tryb_rys = false;
                	break;
            }
            return true;
        }

I have something like that but when i draw this rectangle it leave a trace. I only want a few lines of code to fix this.

How to convert code from C + + to Java for Android?

2 solutions

Solution 1

Solution 2

Add your solution here

Preview 0