安卓從view中獲取bitmap，給Bitmap添加背景，以及保存bitmap到相冊或指定文件夾

工具類 ViewToBitmapUtils.kt

import android.app.Activity
import android.graphics.*
import android.view.View
import android.graphics.Bitmap
import android.text.TextUtils


/**
 * 把任意view保存到bitmap中
 */
class ViewToBitmapUtils {
    companion object{
        //從view 中獲取bitmap
        fun getViewBitmap(view: View?):Bitmap?{
            if(view==null){
                return null
            }
            var dp20 = Utils.dp2px(20f)
            var dp30 = Utils.dp2px(30f)

            val cardBitmap = Bitmap.createBitmap(view.width,view.height,Bitmap.Config.ARGB_8888)
            var cardCanvas = Canvas(cardBitmap)
//            cardCanvas.drawFilter = PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG or Paint.FILTER_BITMAP_FLAG)
            view.draw(cardCanvas)//繪製前景

            val bgBitmap = Bitmap.createBitmap(view.width+dp20*2,view.height+dp30*2,Bitmap.Config.ARGB_8888)
            val bgCanvas = Canvas(bgBitmap);
            bgCanvas.drawFilter = PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG or Paint.FILTER_BITMAP_FLAG)
            bgCanvas.drawColor(Color.parseColor("#F1F1F1"))

            bgCanvas.drawBitmap(cardBitmap,dp20.toFloat(),dp30.toFloat(), Paint())
            return bgBitmap
        }

        //合併兩個view到一個bitmap，一樣給這兩個view增長一個背景圖片
        fun combineView(topView: View,bottomView: View): Bitmap {
            val topWidth = topView.width.toFloat()
            val topHeight = topView.height.toFloat()

            var dp20 = Utils.dp2px(20f)
            var dp30 = Utils.dp2px(30f)

            bottomView.measure(View.MeasureSpec.makeMeasureSpec(topView.width,View.MeasureSpec.EXACTLY),View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED));
            bottomView.layout(0,0,topView.width,bottomView.measuredHeight);

            val bottomWidth = bottomView.width.toFloat()
            val bottomHeight = bottomView.height.toFloat()

            val width = Math.max(topWidth,bottomWidth)+dp20*2 //取最大的寬度做爲最終寬度 增長20dp*2
            val height = topHeight + bottomHeight + dp30*2 //計算總高度 增長 30dp*2

            val topBitmap = Bitmap.createBitmap(width.toInt(), topHeight.toInt(), Bitmap.Config.ARGB_8888)//頂部圖片
            topView.draw(Canvas(topBitmap))

            val bottomBitmap = Bitmap.createBitmap(width.toInt(), bottomHeight.toInt(), Bitmap.Config.ARGB_8888)//底部圖片
            bottomView.draw(Canvas(bottomBitmap))

            val bitmap = Bitmap.createBitmap(width.toInt(), height.toInt(), Bitmap.Config.ARGB_8888)//底圖
            val canvas = Canvas(bitmap)//畫布
            canvas.drawFilter = PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG or Paint.FILTER_BITMAP_FLAG)
            canvas.drawColor(Color.parseColor("#D9D9D9"))
            val paint = Paint()

            canvas.drawBitmap(topBitmap, dp20.toFloat(), dp30.toFloat(), paint)//畫頂部
            canvas.drawBitmap(bottomBitmap, dp20.toFloat(), topHeight+dp30.toFloat(), paint)//畫底部
            return bitmap
        }

        //把bitmap 保存到文件
        fun bitmapToFile(context: Activity, bitmap:Bitmap?, endName:String, isSave:Boolean): String? {
            if(bitmap==null || TextUtils.isEmpty(endName)){
                return null
            }
            if(isSave){
                return ImageUtil.saveAnyImageToGallery(context,bitmap,"share_$endName.jpg")
            }else {
                return ImageUtil.saveImageToTempDir(context,bitmap,"share_$endName.jpg")
            }
        }
    }
}
複製代碼

ImageUtils.java 方法

/**保存任意圖片到相冊
     *
     * @param context
     * @param bmp 圖片位圖
     * @param fileName 圖片文件名字，不含路徑
     */
    public static String saveAnyImageToGallery(Context context, Bitmap bmp,String fileName) {
        // 首先保存圖片
        String storePath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).getAbsolutePath() + File.separator;
        File appDir = new File(storePath);
        if (!appDir.exists()) {
            appDir.mkdirs();
        }
        String filePath = storePath + File.separator + fileName;
        createImgToFile(bmp, filePath);
        FileUtil.fileScan(context, filePath);
        return filePath;
    }
    
    
    public static void createImgToFile(Bitmap bmp, String filename) {

        FileOutputStream b = null;
        try {
            b = new FileOutputStream(filename);
            bmp.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把數據寫入文件
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } finally {
            try {
                if(b!=null){
                    b.flush();
                    b.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    
    
    /**保存任意圖片到SDcard koolearn temp臨時文件夾下 用完就刪除的那種
     *
     * @param context
     * @param bmp 圖片位圖
     * @param fileName 圖片文件名字，不含路徑
     */
    public static String saveImageToTempDir(Context context, Bitmap bmp,String fileName) {
        // 首先保存圖片
        File storePath = new File(FileUtil.createKoolearnDir()+File.separator+"temp","share_"+System.currentTimeMillis()+".jpg");
        if (!storePath.getParentFile().exists()) {
            storePath.mkdirs();
        }else{
            //有此文件夾則刪除此文件夾下面全部圖片，作到每次都清空
            for (int i=0;i<storePath.getParentFile().listFiles().length;i++){
                storePath.getParentFile().listFiles()[i].delete();
            }
        }
        createImgToFile(bmp, storePath.getAbsolutePath());
        return storePath.getAbsolutePath();
    }
複製代碼