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Android Build an Interactive Story App (Retired) Finishing the User Interface Ending the Story

Patrick Koch
Patrick Koch
40,498 Points
Posted by Patrick Koch
Patrick Koch
40,498 Points

call function within creation that function,.....what?

Hi volks,

here is something new for me, Ben was calling the loadPage() function in the loadPage function itself, obviously its working but its a new practise to me. first the code:

private void loadPage(int choice) {
        mCurrentPage = mStory.getPage(choice);

        Drawable drawable = getResources().getDrawable(mCurrentPage.getImageId());
        mImageView.setImageDrawable(drawable);

        String pageText = mCurrentPage.getText();
        // Add the name if placeholder included. Won't add if no placeholder
        pageText = String.format(pageText, mName);
        mTextView.setText(pageText);

        if (mCurrentPage.isFinal()) {
            mChoice1.setVisibility(View.INVISIBLE);
            mChoice2.setText("PLAY AGAIN");
            mChoice2.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    finish();
                }
            });
        }
        else {
            mChoice1.setText(mCurrentPage.getChoice1().getText());
            mChoice2.setText(mCurrentPage.getChoice2().getText());

            mChoice1.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    int nextPage = mCurrentPage.getChoice1().getNextPage();
                    loadPage(nextPage);
                }
            });

            mChoice2.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    int nextPage = mCurrentPage.getChoice2().getNextPage();
                    loadPage(nextPage);
                }
            });
        }
    }

What I understande, if we run the loadPage function its executing down till the loadPage() function is called again, and its starts to execute from the top. Are those thoughts right or how is that working?

Probably somebody can explain it to me, thanks

greetings Patrick

1 Answer

kunalshitut
kunalshitut
5,872 Points

You are correct. See, what happens is that when you call loadpage(nextPage); inside loadpage(), the loadpage() method is called again with nextPage in place of choice. This is called 'recursion', a programming concept in which a method calls itself again and again . Googling it should give you a better idea.