我有一个Bitmap图像,我必须将其存储在SD卡的文件夹中,我的代码如下所示。它按预期创建文件夹和文件,但图像未存储到文件中,它仍然是一个空文件...任何人都可以告诉我有什么问题吗?
Bitmap merged = Bitmap.createBitmap(mDragLayer.getChildAt(0).getWidth(), mDragLayer.getChildAt(0).getHeight(), Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(merged);
// save to folder in sd card
try {
File imagesFolder = new File(Environment.getExternalStorageDirectory(), "folder");
if(!imagesFolder.exists())
imagesFolder.mkdirs();
int imageNum;
if(imagesFolder.list()==null)
imageNum = 1;
else
imageNum = imagesFolder.list().length + 1;
String fileName = "file_" + String.valueOf(imageNum) + ".jpg";
File output = new File(imagesFolder, fileName);
while(output.exists()){
imageNum++;
fileName = "file_" + String.valueOf(imageNum) + ".jpg";
output = new File(imagesFolder, fileName);
}
OutputStream fOut = new FileOutputStream(output);
merged.compress(Bitmap.CompressFormat.JPEG, 100, fOut);
fOut.flush();
fOut.close();
Toast.makeText(getApplicationContext(), "Saved", Toast.LENGTH_SHORT).show();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
答案 0 :(得分:17)
首先添加AndroidManifest.xml的权限
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
然后在Java文件中写下如下。
String extr = Environment.getExternalStorageDirectory().toString();
File mFolder = new File(extr + "/MyApp");
if (!mFolder.exists()) {
mFolder.mkdir();
}
String strF = mFolder.getAbsolutePath();
File mSubFolder = new File(strF + "/MyApp-SubFolder");
if (!mSubFolder.exists()) {
mSubFolder.mkdir();
}
String s = "myfile.png";
f = new File(mSubFolder.getAbsolutePath(),s);
更新
String strMyImagePath = f.getAbsolutePath();
FileOutputStream fos = null;
try {
fos = new FileOutputStream(f);
bitmap.compress(Bitmap.CompressFormat.PNG,70, fos);
fos.flush();
fos.close();
// MediaStore.Images.Media.insertImage(getContentResolver(), b, "Screen", "screen");
}catch (FileNotFoundException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
答案 1 :(得分:7)
你只需要一个位图
你必须传递一个存储图像的路径
Bitmap b = pagesView.getDrawingCache();
b.compress(CompressFormat.JPEG, 100, new FileOutputStream(Environment.getExternalStorageDirectory() + "/NameOfFile.jpg"));
并且您必须在Manifest文件中添加权限..
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
答案 2 :(得分:6)
使用复杂的代码不要让它变得非常简单,请尝试下面的代码。
在你的SD卡中创建第一个目录:
public static String strpath = android.os.Environment.getExternalStorageDirectory().toString();
public static String dirName = "DIR_NAME";
File makeDirectory = new File(strpath+"/"+dirName);
makeDirectory.mkdir();
然后你应该制作两个String Var,如下所示:
String filename = "yourImageName".jpg";
String dirpath =strpath + "/"+dirName + "/";
制作文件变量:
File storagePath = new File(dirpath);
File myImage = new File(storagePath, filename);
outStream = new FileOutputStream(myImage);
outStream.write(data);
outStream.close();
希望这对您有所帮助。