J2ME游戏只移植到Android平台(一)

为了让J2ME游戏无需大的改动就可以在Android的平台下，我是在利用Android平台的类库拼接成J2ME类，如用Android的canvas类和paint类拼接成J2me的Graphics类，用Bitmap重写J2ME的Image类。最终得到一个中间件包！

 

Font类的代码：

import android.graphics.Paint;
import android.graphics.Paint.FontMetrics;
import android.graphics.Typeface;

//复写J2ME的Font类中的变量和函数
public class Font {

	public static final int FACE_MONOSPACE = 32;
	public static final int FACE_PROPORTIONAL = 64;
	public static final int FACE_SYSTEM = 0;

	public static final int FONT_INPUT_TEXT = 1;
	public static final int FONT_STATIC_TEXT = 0;

	public static final int SIZE_LARGE = 32;
	public static final int SIZE_MEDIUM = 24;
	public static final int SIZE_SMALL = 16;

	public static final int STYLE_BOLD = 1;
	public static final int STYLE_ITALIC = 2;
	public static final int STYLE_PLAIN = 0;
	public static final int STYLE_UNDERLINED = 4;

	//在J2ME的graphics 在android 就是Paint
	//Paint 其实要比graphics 分装的东西要多，包括字体的大小也是有其控制的
	private Paint paint;
	private int face, style, size;

	//measureText 来测量字体的长度
	int charsWidth(char[] ch, int offset, int length) {
		return (int) paint.measureText(ch, offset, length);
	}

	int charWidth(char ch) {
		char[] charArr = new char[1];
		charArr[0] = ch;
		return (int) paint.measureText(charArr, 0, charArr.length);
	}

	int getBaselinePosition() {
		FontMetrics fm = paint.getFontMetrics();
		return (int) fm.bottom;
	}

	private Font() {
		face = FACE_SYSTEM;
		style = STYLE_PLAIN;
		size = SIZE_MEDIUM;
		setPaintAtt(paint);
	}

	private Font(int face, int style, int size) {
		this.face = face;
		this.style = style;
		this.size = size;
		setPaintAtt(paint);
	}

	private Font(Paint paint, int face, int style, int size) {
		setPaintAtt(paint);
	}

	//android 中字体的样式都是由Typeface控制
	public void setPaintAtt(Paint paint) {

		this.paint = paint;
		if (paint == null)
			paint = new Paint();

		switch (face) {
		case FACE_MONOSPACE:
			paint.setTypeface(Typeface.MONOSPACE);
			break;
		case FACE_PROPORTIONAL:
			break;
		case FACE_SYSTEM:
			paint.setTypeface(Typeface.DEFAULT);
			break;
		}
		paint.setAntiAlias(true);
		switch (style) {
		case STYLE_BOLD:
			paint.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD));
			break;
		case STYLE_ITALIC:
			paint.setTypeface(Typeface.defaultFromStyle(Typeface.ITALIC));
			break;
		case STYLE_PLAIN:
			paint.setTypeface(Typeface.defaultFromStyle(Typeface.NORMAL));
			break;
		case STYLE_UNDERLINED:
			// paint.setTypeface(Typeface.SERIF);
			break;
		}
		paint.setTextSize(size);
	}

	public static Font getFont(int face, int style, int size) {
		Font font = new Font(face, style, size);
		return font;
	}

	public static Font getFont(int fontSpecifier) {
		switch (fontSpecifier) {
		case FONT_INPUT_TEXT:
			return getFont(FACE_SYSTEM, SIZE_MEDIUM, STYLE_UNDERLINED);
		case FONT_STATIC_TEXT:
			return getFont(FACE_SYSTEM, SIZE_MEDIUM, STYLE_ITALIC);
		default:
			return new Font();
		}
	}

	public static Font getDefaultFont() {
		return new Font();
	}

	public static Font getFont(Paint paint) {
		Font font = new Font();
		font.paint = paint;
		font.size = (int) paint.getTextSize();
		return font;
	}

	public int getFace() {
		// Typeface tf = paint.getTypeface();
		return 0;
	}

	//这里字体的高度复写了一下，大家请参考一下api
	public int getHeight() {
		FontMetrics fm = paint.getFontMetrics();
		return (int) Math.ceil(fm.descent - fm.ascent);
	}

	public int getSize() {
		return (int) paint.getTextSize();
	}

	public int getStyle() {
		Typeface tf = paint.getTypeface();
		return tf.getStyle();
	}

	public boolean isBold() {
		Typeface tf = paint.getTypeface();
		return tf.isBold();
	}

	public boolean isItalic() {
		Typeface tf = paint.getTypeface();
		return tf.isItalic();
	}

	public boolean isPlain() {
		Typeface tf = paint.getTypeface();
		return tf.isItalic();
	}

	public boolean isUnderlined() {
		return paint.isUnderlineText();
	}

	public int stringWidth(String str) {
		return (int) paint.measureText(str);
	}

	public int substringWidth(String str, int offset, int len) {
		return (int) paint.measureText(str.substring(offset, offset + len));
	}

}

 

 

Image类

import java.io.IOException;
import java.io.InputStream;

import lxs.slg.Game;

import android.content.res.AssetManager;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;

public class Image {
	//在android 中 图片对象是Bitmap
	private Bitmap img;
	private int alpha;

	private Image() {
		img = null;
		alpha = 0xff;
	}

	private Image(Bitmap img, int alpha) {
		this.img = img;
		this.alpha = alpha;
	}

	private Image(Image source) {
		this.img = source.img;
		this.alpha = source.alpha;
	}

	public static Image createImage(String src) {
		if (src.startsWith("/")) {
			src = src.substring(1);
		}

		//当前的activity对象
		//如下是标准的读取Bitmap方法
		Resources resources = Game.father.getResources();
		AssetManager assetManager = resources.getAssets();
		InputStream in = null;
		Bitmap img = null;
		try {
			in = assetManager.open(src);
			img = BitmapFactory.decodeStream(in);
			in.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return new Image(img, 0xff);
	}

	public static Image createImage(byte[] imageData, int imageOffset,
			int imageLength) {
		//从byte对象创建一个Bitmap 是由BitmapFactory函数负责的
		Bitmap img = BitmapFactory.decodeByteArray(imageData, imageOffset,
				imageLength);
		return new Image(img, 0xff);
	}

	public static Image createImage(Image source) {
		return new Image(source);
	}

	public static Image createImage(Image image, int x, int y, int width,
			int height, int transform) {
		Bitmap bmp = Bitmap.createBitmap(image.img, x, y, width, height);
		Paint paint = new Paint();
		paint.setAlpha(image.alpha);

		Image tImage = createImage(width, height);
		Canvas canvas = new Canvas(tImage.img);
		//调用Graphics函数 获取旋转矩阵
		Matrix mMatrix = Graphics.getTransformMetrix(transform, width, height);
		//调用如下的函数将其绘制在兴建的Bitmap对象上
		canvas.drawBitmap(bmp, mMatrix, paint);

		return tImage;
	}

	public static Image createImage(InputStream stream) {
		Bitmap img = BitmapFactory.decodeStream(stream);
		return new Image(img, 0xff);
	}

	public static Image createImage(int width, int height) {
		//android 中创建Image 对象的函数
		Bitmap img = Bitmap
				.createBitmap(width, height, Bitmap.Config.ARGB_8888);
		return new Image(img, 0xff);
	}

	public static Image createRGBImage(int[] rgb, int width, int height,
			boolean processAlpha) {
		Bitmap img;
		if (processAlpha) {
			img = Bitmap.createBitmap(rgb, width, height,
					Bitmap.Config.ARGB_8888);
		} else {
			//不需要支持透明的图片，我们采用差分颜色图片点阵标识
			img = Bitmap
					.createBitmap(rgb, width, height, Bitmap.Config.RGB_565);
		}
		return new Image(img, 0xff);
	}

	//获取图片的绘制对象
	public Graphics getGraphics() {
		Canvas canvas = new Canvas(img);
		Paint paint = new Paint();
		paint.setAlpha(alpha);
		return new Graphics(canvas, paint);
	}

	public void setAlpha(int alpha) {
		this.alpha = alpha;
	}

	public int getAlpha() {
		return alpha;
	}

	public Bitmap getImg() {
		return img;
	}

	public int getHeight() {
		return img.getHeight();
	}

	public void getRGB(int[] rgbData, int offset, int scanlength, int x, int y,
			int width, int height) {
		img.getPixels(rgbData, offset, scanlength, x, y, width, height);
	}

	public int getWidth() {
		return img.getWidth();
	}

	boolean isMutable() {
		return img.isMutable();
	}

	public void replaceColor(int newColor, int oldColor) {
		int width = img.getWidth();
		int height = img.getHeight();
		int[] pixels = new int[width * height];
		img.getPixels(pixels, 0, width, 0, 0, width, height);

		for (int i = 0; i < pixels.length; i++) {
			if ((pixels[i] | 0x00ffffff) == (oldColor | 0x00ffffff)) {
				pixels[i] = oldColor;
			}
		}
		img = Bitmap.createBitmap(pixels, 0, 0, height, height,
				Bitmap.Config.ARGB_8888);
	}
}