Android View转成Bitmap

最新推荐文章于 2024-05-29 17:01:20 发布

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本文介绍了如何将不同类型的Android视图（如ScrollView、RelativeLayout和Canvas）转换为Bitmap，并提供了将图片保存到设备相册的方法。包括代码示例，展示了具体的实现过程。

一、View 转 Bitmap的几种情况

1、ScrollView 转成Bitmap

public void convertViewToBitmap(ScrollView scrollView) {
    int h = 0;
    for (int i = 0; i < scrollView.getChildCount(); i++) {
        h += scrollView.getChildAt(i).getHeight();
    }
    // 创建对应大小的bitmap
    posterBitmap = Bitmap.createBitmap(scrollView.getWidth(), h, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(posterBitmap);
    scrollView.draw(canvas);
}

2、RelativeLayout 转成Bitmap

这个View如果没有再布局，则需要设置宽高才能转

private Bitmap createBitmap(RelativeLayout view) {
    Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.ARGB_8888);
    Canvas c = new Canvas(bitmap);
    c.drawColor(Color.WHITE);
    view.draw(c);
    return bitmap;
}

3、Canvas转成Bitmap

public Bitmap getBitmap() {
        int w = UiUtil.dip2px(64), h = UiUtil.dip2px(72);
        String mstrTitle = "感受Android带给我们的新体验";
        final Bitmap mbmpTest = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(mbmpTest);
        canvas.drawColor(Color.BLACK);
        Paint p = new Paint();
        String familyName = "宋体";
        Typeface font = Typeface.create(familyName, Typeface.BOLD);
        p.setColor(Color.RED);
        p.setTypeface(font);
        p.setTextSize(22);
        canvas.drawText(mstrTitle, 0, 100, p);

        Bitmap bitmap1 = BitmapFactory.decodeResource(getResources(), R.mipmap.public_back);
        Bitmap bitmap2 = BitmapFactory.decodeResource(getResources(), R.mipmap.public_audio_introduce3);
        Bitmap bitmap3 = BitmapFactory.decodeResource(getResources(), R.mipmap.public_praise_s);
        canvas.drawBitmap(bitmap1, 0, 0, p);
        canvas.drawBitmap(bitmap2, 30, 30, p);
        canvas.drawBitmap(bitmap3, 60, 60, p);
        bitmap1.recycle();
        bitmap2.recycle();
        bitmap3.recycle();
        bitmap1=null;
        bitmap2=null;
        bitmap3=null;
        return mbmpTest;
    }

二、保存图片到相册

    /**
     * 屏幕截图保存
     */
    public static void saveScreenShot(View view,BaseActivity activity) {
        Bitmap bitmap = BitmapUtil.loadBitmapFromView(view);
        String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
        OutputStream outStream = null;
        String filename;//声明文件名
        //以保存时间为文件名
        Date date = new Date(System.currentTimeMillis());
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
        filename = sdf.format(date);
        File file = new File(extStorageDirectory, filename + ".JPEG");//创建文件，第一个参数为路径，第二个参数为文件名
        try {
            outStream = new FileOutputStream(file);//创建输入流
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, outStream);
            outStream.close();

            //这三行可以实现相册更新
            Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
            Uri uri = Uri.fromFile(file);
            intent.setData(uri);
            activity.sendBroadcast(intent);//这个广播的目的就是更新图库，发了这个广播进入相册就可以找到你保存的图片了

            activity.runOnUiThread(() -> Toast.makeText(activity, "保存成功", Toast.LENGTH_SHORT).show());
        } catch (Exception e) {
            activity.runOnUiThread(() -> Toast.makeText(activity, "保存失败", Toast.LENGTH_SHORT).show());
        }
    }