屏幕截图另存为自动生成的文件名

Question

我做了一个按钮，以采取截图和保存到图片文件夹。我将它设置为保存在名称capture.jpeg下，但我希望它保存为像这样的cafe001.jpeg，cafe002.jpeg。你能告诉我如何将它保存为时间格式.jpeg吗？谢谢你事先的帮助

container = (LinearLayout) findViewById(R.id.LinearLayout1);
        Button captureButton = (Button) findViewById(R.id.captureButton);
        captureButton.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
            container.buildDrawingCache();
            Bitmap captureView = container.getDrawingCache();
            FileOutputStream fos;
            try {
                fos = new FileOutputStream(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString() + "capture.jpeg");
                captureView.compress(Bitmap.CompressFormat.JPEG, 100, fos);
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }
            Toast.makeText(getApplicationContext(),
                    "Captured under Pictures drectory", Toast.LENGTH_LONG)
                    .show();
        }
    });

Answer 1

你基本上有几个选择...

列出目录中的所有文件并简单地将文件计数增加1并使用...

File[] files = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString()).
    listFiles(new FileFilter() {
        public boolean accept(File pathname) {
            String name = pathname.getName();
            return pathname.isFile() && name.toLowerCase().startsWith("capture") && name.toLowerCase().endsWith(".jpeg");
        }
});

int fileCount = files.length();

fos = new FileOutputStream(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString() + 
    "capture" + fileCount + ".jpeg");

当然，如果存在一个具有相同索引的文件，这并不考虑在内...

File[] files = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString()).
    listFiles(new FileFilter() {
        public boolean accept(File pathname) {
            String name = pathname.getName();
            return pathname.isFile() && name.toLowerCase().startsWith("capture") && name.toLowerCase().endsWith(".jpeg");
        }
});

Arrays.sort(files);
File last = files[files.length - 1];

Pattern pattern = Pattern.compile("[0-9]+");
Matcher matcher = pattern.matcher(last.getName());

int index = 1;
if (matcher.find()) {
    String match = matcher.group();
    index = Integer.parseInt(match) + 1;
}

String fileName = "capture" + index + ".jpeg"