在Android上将文本转换为图像文件

Question

我有一个文本文件(.txt).我想将其转换为图像(.png或.jpg).例如,在白色背景的黑文本.我该如何以编程方式执行此操作？

Answer 1

我认为多行文本的正确方法是这样的:

String text = "This \nis \nmultiline";

final Rect bounds = new Rect();
TextPaint textPaint = new TextPaint() {
    {
        setColor(Color.WHITE);
        setTextAlign(Paint.Align.LEFT);
        setTextSize(20f);
        setAntiAlias(true);
    }
};
textPaint.getTextBounds(text, 0, text.length(), bounds);
StaticLayout mTextLayout = new StaticLayout(text, textPaint,
            bounds.width(), Alignment.ALIGN_NORMAL, 1.0f, 0.0f, false);
int maxWidth = -1;
for (int i = 0; i < mTextLayout.getLineCount(); i++) {
    if (maxWidth < mTextLayout.getLineWidth(i)) {
        maxWidth = (int) mTextLayout.getLineWidth(i);
    }
}
final Bitmap bmp = Bitmap.createBitmap(maxWidth , mTextLayout.getHeight(),
            Bitmap.Config.ARGB_8888);
bmp.eraseColor(Color.BLACK);// just adding black background
final Canvas canvas = new Canvas(bmp);
mTextLayout.draw(canvas);
FileOutputStream stream = new FileOutputStream(...); //create your FileOutputStream here
bmp.compress(CompressFormat.PNG, 85, stream);
bmp.recycle();
stream.close();

Answer 2

这个(未经测试的)代码应该让你走上正确的轨道.

void foo(final String text) throws IOException{
    final Paint textPaint = new Paint() {
        {
            setColor(Color.WHITE);
            setTextAlign(Paint.Align.LEFT);
            setTextSize(20f);
            setAntiAlias(true);
        }
    };
    final Rect bounds = new Rect();
    textPaint.getTextBounds(text, 0, text.length(), bounds);

    final Bitmap bmp = Bitmap.createBitmap(bounds.width(), bounds.height(), Bitmap.Config.RGB_565); //use ARGB_8888 for better quality
    final Canvas canvas = new Canvas(bmp);
    canvas.drawText(text, 0, 20f, textPaint);
    FileOutputStream stream = new FileOutputStream(...); //create your FileOutputStream here
    bmp.compress(CompressFormat.PNG, 85, stream);
    bmp.recycle();
    stream.close();
}