Breaking large text into pages in android text swi

2019-03-16 14:12发布

问题:

I am in the process of developing an e-book reader application for android 3.0 tablets. To begin with I have a large chunk of String data. I want to split/break that String into pages based on the screen size of the device [I am planning to use text switcher or view flipper]. Though I tried using getWindowManager() method I could not get the preferred results.

In the following thread it is mentioned that Text Switcher automatically breaks the text according to the screen size. But I do not think so. Managing text in android applicaiton like in a eBook

This is the logic I used :

    // retreiving the flipper       
    flipper = (ViewFlipper) findViewById(R.id.new_view_flipper);        

    // obtaining screen dimensions      
    Display display = getWindowManager().getDefaultDisplay(); 
    int screenWidth = display.getWidth();
    int screenHeight = display.getHeight();

    // contentString is the whole string of the book

    while (contentString != null && contentString.length() != 0) 
    {
        totalPages ++;

        // creating new textviews for every page
        TextView contentTextView = new TextView(this);
        contentTextView.setWidth(ViewGroup.LayoutParams.FILL_PARENT);
        contentTextView.setHeight(ViewGroup.LayoutParams.FILL_PARENT);
        contentTextView.setMaxHeight(screenHeight);
        contentTextView.setMaxWidth(screenWidth);

        float textSize = contentTextView.getTextSize();
        Paint paint = new Paint();
        paint.setTextSize(textSize);

        int numChars = 0;
        int lineCount = 0;
        int maxLineCount = screenHeight/contentTextView.getLineHeight();
        contentTextView.setLines(maxLineCount);

        while ((lineCount < maxLineCount) && (numChars < contentString.length())) {
            numChars = numChars + paint.breakText(contentString.substring(numChars), true, screenWidth, null);
            lineCount ++;
        }

        // retrieve the String to be displayed in the current textbox
        String toBeDisplayed = contentString.substring(0, numChars);
        contentString = contentString.substring(numChars);
        contentTextView.setText(toBeDisplayed);
        flipper.addView(contentTextView);


        numChars = 0;
        lineCount = 0;
    }

回答1:

This is all you need to make your code work.

    DisplayMetrics dm = new DisplayMetrics();
    getWindowManager().getDefaultDisplay().getMetrics(dm);
    int screenWidth = dm.widthPixels;
    int screenHeight= dm.heightPixels;

Replace your following code block with mine. It will work.

Display display = getWindowManager().getDefaultDisplay(); 
int screenWidth = display.getWidth();
int screenHeight = display.getHeight();