实用代码块记录10

Bitmap操作

import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStream;import android.annotation.SuppressLint;import android.content.Context;import android.graphics.Bitmap;import android.graphics.Bitmap.Config;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Matrix;import android.graphics.Paint;import android.graphics.PorterDuff.Mode;import android.graphics.PorterDuffXfermode;import android.graphics.Rect;import android.graphics.RectF;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.util.Base64;public class BitmapUtils {    /**     * convert Bitmap to byte array     *      * @param b     * @return     */    public static byte[] bitmapToByte(Bitmap b) {        if (b == null) {            return null;        }        ByteArrayOutputStream o = new ByteArrayOutputStream();        b.compress(Bitmap.CompressFormat.PNG, 100, o);        return o.toByteArray();    }    /**     * convert byte array to Bitmap     *      * @param b     * @return     */    public static Bitmap byteToBitmap(byte[] b) {        return (b == null || b.length == 0) ? null : BitmapFactory                .decodeByteArray(b, 0, b.length);    }    /**     * convert Drawable to Bitmap     *      * @param d     * @return     */    public static Bitmap drawableToBitmap(Drawable d) {        return d == null ? null : ((BitmapDrawable) d).getBitmap();    }    /**     * convert Bitmap to Drawable     *      * @param b     * @return     */    public static Drawable bitmapToDrawable(Bitmap b) {        return b == null ? null : new BitmapDrawable(b);    }    /**     * convert Drawable to byte array     *      * @param d     * @return     */    public static byte[] drawableToByte(Drawable d) {        return bitmapToByte(drawableToBitmap(d));    }    /**     * convert byte array to Drawable     *      * @param b     * @return     */    public static Drawable byteToDrawable(byte[] b) {        return bitmapToDrawable(byteToBitmap(b));    }    /**     * 获得圆角图片     *      * @author huxj     * @param bitmap     *            Bitmap资源     * @param roundPx     *            弧度     * @return Bitmap 圆角Bitmap资源     */    public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, float roundPx) {        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),                bitmap.getHeight(), Config.ARGB_8888);        Canvas canvas = new Canvas(output);        final int color = 0xff424242;        final Paint paint = new Paint();        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());        final RectF rectF = new RectF(rect);        paint.setAntiAlias(true);        canvas.drawARGB(0, 0, 0, 0);        paint.setColor(color);        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));        canvas.drawBitmap(bitmap, rect, rect, paint);        return output;    }    /**     * 保存图片至本地文件     */    public static void saveBitmapToFile(Bitmap bmp, String dir, String path) {        File file = new File(dir);        if (!file.isDirectory()) {            file.mkdirs();        }        File f = new File(path);        try {            f.createNewFile();            FileOutputStream fOut = null;            fOut = new FileOutputStream(f);            bmp.compress(Bitmap.CompressFormat.PNG, 100, fOut);            fOut.flush();            fOut.close();        } catch (Exception e) {            e.printStackTrace();        }    }    /** 读取本地图片文件，压缩至合适宽高，返回bitmap */    public static Bitmap getBitmapFromFile(String path, int mScreenWidth,            int mScreenHeight) {        if (path != null) {            BitmapFactory.Options options = null;            InputStream is = null;            try {                options = new BitmapFactory.Options();                options.inJustDecodeBounds = true;                is = new FileInputStream(path);                BitmapFactory.decodeStream(is, null, options);                int w = options.outWidth;                int h = options.outHeight;                options = new BitmapFactory.Options();                options.inSampleSize = Math.max((int) (w / mScreenWidth), h                        / mScreenHeight);                options.inJustDecodeBounds = false;                is.close();                is = new FileInputStream(path);                return BitmapFactory.decodeStream(is, null, options);            } catch (Throwable e) {                e.printStackTrace();            } finally {                try {                    if (is != null)                        is.close();                } catch (Exception e) {                    e.printStackTrace();                }            }        }        return null;    }    /** 读取本地图片，并压缩scale倍，返回bitmap */    public static Bitmap getScaleBitmapFromFile(String path, int scale) {        if (path != null) {            try {                BitmapFactory.Options options = new BitmapFactory.Options();                InputStream is = new FileInputStream(path);                options = new BitmapFactory.Options();                options.inSampleSize = scale;                options.inJustDecodeBounds = false;                is.close();                is = new FileInputStream(path);                return BitmapFactory.decodeStream(is, null, options);            } catch (Throwable e) {                e.printStackTrace();            }        }        return null;    }    /** 读取资源图片，返回bitmap */    public static Bitmap getBitmapForResource(Context context, int resourceId,            int mScreenWidth, int mScreenHeight) {        try {            BitmapFactory.Options options = new BitmapFactory.Options();            options.inJustDecodeBounds = true;            BitmapFactory.decodeResource(context.getResources(), resourceId,                    options);            int w = options.outWidth;            int h = options.outHeight;            options = new BitmapFactory.Options();            options.inSampleSize = Math.max((int) (w / mScreenWidth), h                    / mScreenHeight);            options.inJustDecodeBounds = false;            return BitmapFactory.decodeResource(context.getResources(),                    resourceId, options);        } catch (Throwable e) {            e.printStackTrace();        }        return null;    }    @SuppressLint("NewApi")    public static Bitmap stringtoBitmap(String string) {        // 将字符串转换成Bitmap类型        Bitmap bitmap = null;        try {            byte[] bitmapArray;            bitmapArray = Base64.decode(string, Base64.DEFAULT);            bitmap = BitmapFactory.decodeByteArray(bitmapArray, 0,                    bitmapArray.length);        } catch (Exception e) {            e.printStackTrace();        }        return bitmap;    }    /**     * 处理图片     *      * @param bm     *            所要转换的bitmap     * @param newWidth新的宽     * @param newHeight新的高     * @return 指定宽高的bitmap     */    public static Bitmap scaleImg(Bitmap bm, int newWidth, int newHeight) {        // 获得图片的宽高        int width = bm.getWidth();        int height = bm.getHeight();        // 计算缩放比例        float scaleWidth = ((float) newWidth) / width;        float scaleHeight = ((float) newHeight) / height;        // 取得想要缩放的matrix参数        Matrix matrix = new Matrix();        matrix.postScale(scaleWidth, scaleHeight);        // 得到新的图片        Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix,                true);        return newbm;    }    /**     * 处理图片     *      * @param bm     *            所要转换的bitmap ，按宽度保持比例     * @param newWidth新的宽     * @return 指定宽的bitmap     */    public static Bitmap scaleImg(Bitmap bm, int newWidth) {        // 获得图片的宽高        int width = bm.getWidth();        int height = bm.getHeight();        // 计算缩放比例        float scaleWidth = ((float) newWidth) / width;        // 取得想要缩放的matrix参数        Matrix matrix = new Matrix();        matrix.postScale(scaleWidth, scaleWidth);        // 得到新的图片        Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix,                true);        return newbm;    }}