編輯:關於Android編程
收集了很多bitmap相關的處理方法,幾乎全部應用在項目中,所以特記錄下!
package com.tmacsky.utils; import java.io.ByteArrayOutputStream; import java.io.IOException; import android.content.Context; 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; import android.graphics.PixelFormat; import android.graphics.PorterDuffXfermode; import android.graphics.Rect; import android.graphics.RectF; import android.graphics.Bitmap.Config; import android.graphics.PorterDuff.Mode; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.view.View; import android.view.View.MeasureSpec; public class ImageUtils { //--->bitmap相關 //參考網站http://www.cnblogs.com/fighter/archive/2012/02/20/android-bitmap-drawable.html // 見博客:http://blog.sina.com.cn/s/blog_afb547c60101j7qn.html /** * View轉成bitmap * @param view * @return */ public static Bitmap convertViewToBitmap(View view) { view.setDrawingCacheEnabled(true); view.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED)); view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight()); view.buildDrawingCache(); return view.getDrawingCache(); } /** * 縮放Drawable * @param drawable * @param w 縮放後需要的寬度 * @param h 縮放後需要的高度 * @return */ public static Drawable zoomDrawable(Drawable drawable, int w, int h) { int width = drawable.getIntrinsicWidth(); int height = drawable.getIntrinsicHeight(); // drawable轉換成bitmap Bitmap oldbmp = drawableToBitmap(drawable); // 創建操作圖片用的Matrix對象 Matrix matrix = new Matrix(); // 計算縮放比例 float sx = ((float) w / width); float sy = ((float) h / height); // 設置縮放比例 matrix.postScale(sx, sy); // 建立新的bitmap,其內容是對原bitmap的縮放後的圖 Bitmap newbmp = Bitmap.createBitmap(oldbmp, 0, 0, width, height, matrix, true); return new BitmapDrawable(newbmp); } /** * 縮放bitmap * @param oldBitmap 輸入bitmap * @param newWidth * @param newHeight * @return */ public static Bitmap zoomBitmap(Bitmap oldBitmap, int newWidth, int newHeight) { // 獲得圖片的寬高 int width = oldBitmap.getWidth(); int height = oldBitmap.getHeight(); // 計算縮放比例 float scaleWidth = ((float) newWidth) / width; float scaleHeight = ((float) newHeight) / height; // 取得想要縮放的matrix參數 Matrix matrix = new Matrix(); matrix.postScale(scaleWidth, scaleHeight); // 得到新的圖片 Bitmap newbm = Bitmap.createBitmap(oldBitmap, 0, 0, width, height, matrix, true); return newbm; } /** * 縮放網絡圖片 依賴於zoomBitmap * @param img * @param newWidth * @param newHeight * @return */ public static Bitmap zoomImg(String img, int newWidth, int newHeight) { // 圖片源 Bitmap bm = BitmapFactory.decodeFile(img); if (null != bm) { return zoomBitmap(bm, newWidth, newHeight); } return null; } /** * 縮放網絡圖片 依賴於zoomBitmap * @param context * @param img * @param newWidth * @param newHeight * @return */ public static Bitmap zoomImg(Context context, String img, int newWidth, int newHeight) { // 圖片源 try { Bitmap bm = BitmapFactory.decodeStream(context.getAssets() .open(img)); if (null != bm) { return zoomBitmap(bm, newWidth, newHeight); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } /** * 判斷bitmap是否存在 * @param bitmap * @return */ public static boolean bitmapAvailable(Bitmap bitmap) { return bitmap != null && bitmap.getWidth() > 0 && bitmap.getHeight() > 0; } /** * drawable 轉成bitmap * @param drawable * @return */ public static Bitmap drawableToBitmap(Drawable drawable) { // 取 drawable 的長寬 int w = drawable.getIntrinsicWidth(); int h = drawable.getIntrinsicHeight(); // 取 drawable 的顏色格式 Bitmap.Config config = drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565; // 建立對應 bitmap Bitmap bitmap = Bitmap.createBitmap(w, h, config); // 建立對應 bitmap 的畫布 Canvas canvas = new Canvas(bitmap); drawable.setBounds(0, 0, w, h); // 把 drawable 內容畫到畫布中 drawable.draw(canvas); return bitmap; } /** * Bitmap轉換成Drawable * @param context * @param bitmap * @return */ public static Drawable bitmapToDrawable(Context context,Bitmap bitmap){ //因為BtimapDrawable是Drawable的子類,最終直接使用bd對象即可。 BitmapDrawable bd= new BitmapDrawable(context.getResources(), bitmap); return bd; } /** * 從資源中獲取Bitmap * @param context * @param req R.drawable.icon(eg.) * @return */ public Bitmap getBitmapFromResources(Context context,int req){ Resources res = context.getResources(); Bitmap bmp = BitmapFactory.decodeResource(res, req); return bmp; } /** * Byte[] -> Bitmap的轉換 */ public Bitmap Bytes2Bimap(byte[] b) { if (b.length != 0) { return BitmapFactory.decodeByteArray(b, 0, b.length); } else { return null; } } /** * Bitmap->Byte[]的轉換 * @param bm * @return */ public byte[] Bitmap2Bytes(Bitmap bm) { ByteArrayOutputStream baos = new ByteArrayOutputStream(); bm.compress(Bitmap.CompressFormat.PNG, 100, baos); return baos.toByteArray(); } /** * 獲取圓角圖片 * @param bitmap * @param roundPx 圓角的弧度 * @return */ public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, float roundPx) { int w = bitmap.getWidth(); int h = bitmap.getHeight(); Bitmap output = Bitmap.createBitmap(w, h, Config.ARGB_8888); Canvas canvas = new Canvas(output); final int color = 0xff424242; final Paint paint = new Paint(); final Rect rect = new Rect(0, 0, w, h); 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; } }
廢話不多說了,直接給大家貼代碼了。package com.only.android.app;import java.io.File;import android.app.
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