从ListView保存屏幕截图,打开屏幕截图不会打开最新版本

时间:2017-08-22 15:24:44

标签: android listview screenshot

我尝试将整个ListView的屏幕截图保存为内部存储器中的png并将其发送到其他应用。但如果我再次这样做,屏幕截图不是最新的。它是相同的屏幕截图,但我在发送之前更改了数据。

我使用以下代码创建屏幕截图:

  public static Bitmap getWholeListViewItemsToBitmap(SearchableAdapter adapter, ListView listview ) {
        int itemscount       = adapter.getCount();
        int allitemsheight   = 0;
        List<Bitmap> bmps    = new ArrayList<>();

        for (int i = 0; i < itemscount; i++) {

            View childView = adapter.getView(i, null, listview);
            childView.measure(View.MeasureSpec.makeMeasureSpec(listview.getWidth(), View.MeasureSpec.EXACTLY),
                    View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));

            childView.layout(0, 0, childView.getMeasuredWidth(), childView.getMeasuredHeight());
            childView.setDrawingCacheEnabled(true);
            childView.destroyDrawingCache();
            childView.buildDrawingCache();
            bmps.add(childView.getDrawingCache());
            allitemsheight+=childView.getMeasuredHeight();
        }

        Bitmap bigbitmap    = Bitmap.createBitmap(listview.getMeasuredWidth(), allitemsheight, Bitmap.Config.ARGB_8888);
        Canvas bigcanvas    = new Canvas(bigbitmap);

        Paint paint = new Paint();
        int iHeight = 0;

        for (int i = 0; i < bmps.size(); i++) {
            Bitmap bmp = bmps.get(i);
            bigcanvas.drawBitmap(bmp, 0, iHeight, paint);
            iHeight+=bmp.getHeight();

            bmp.recycle();
            bmp=null;
        }
        return bigbitmap;
    }

此代码保存屏幕截图:

 public static boolean storeScreenshot(Context context, Bitmap screenshot) {
        try {
            File imagePath = new File(context.getCacheDir(), "images");
            if (!imagePath.exists())
                imagePath.mkdirs();
            File newFile = new File(imagePath, "image.png");
            if (newFile.exists()){
                newFile.delete();
                newFile = new File(imagePath, "image.png");
            }
            FileOutputStream stream = new FileOutputStream(newFile.getAbsolutePath()); // overwrites this image every time
            screenshot.compress(Bitmap.CompressFormat.PNG, 100, stream);
            stream.close();
            return true;
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }

此代码打开屏幕截图并使用shareintent发送它:

try {
    Helper.storeScreenshot(getApplicationContext(), Helper.getWholeListViewItemsToBitmap(adapter, listview));
    File imagePath = new File(getApplicationContext().getCacheDir(), "images");
    File screenshot = new File(imagePath, "image.png");
    Uri contentUri = null;
    if (screenshot.exists())
      contentUri = FileProvider.getUriForFile(getApplicationContext(), "com.myApp.fileprovider", screenshot);

    if (contentUri != null) {
      Intent shareIntent = new Intent();
      shareIntent.setAction(Intent.ACTION_SEND);

      shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
      shareIntent.setDataAndType(contentUri, getContentResolver().getType(contentUri));
      shareIntent.putExtra(Intent.EXTRA_STREAM, contentUri);

      startActivity(Intent.createChooser(shareIntent, "App auswählen"));
     }
 }
 catch(Exception e){
 Toast.makeText(getApplicationContext(),"Fehler beim Erstellen des Screenshots!", Toast.LENGTH_LONG);
 }

如果我尝试再次使用更改的数据共享Listview,它总是发送一些旧的屏幕截图。

有人有想法吗?

非常感谢

1 个答案:

答案 0 :(得分:0)

解决方案

  

“如果文件名保持不变,缓存不会更新。我解决了这个问题   删除目录的内容并将文件名设置为   当前日期,以毫秒为单位。 - Gurupad Mamadapur 4月12日17:00“

所以我将save方法的代码更改为:

public static String storeScreenshot(Context context, Bitmap screenshot) {
        try {
            File imagePath = new File(context.getCacheDir(), "images");
            if (!imagePath.exists())
                imagePath.mkdirs();
            File[] imagePathDir = imagePath.listFiles();
            if(imagePathDir != null){
                for (File file : imagePathDir ){
                    file.delete();
                }
            }
            File screenshotFile = new File(imagePath, System.currentTimeMillis()+".png");
            FileOutputStream stream = new FileOutputStream(screenshotFile.getAbsolutePath());
            screenshot.compress(Bitmap.CompressFormat.PNG, 100, stream);
            stream.close();
            return screenshotFile.getName();
        } catch (IOException e) {
            e.printStackTrace();
            return "";
        }

它返回文件名,现在可以正常工作。