问题
this is my code I and I want to save this bitmap on my internal storage. The public boolean saveImageToInternalStorage is a code from google but I don't know how to use it. when I touch button2 follow the button1 action.
public class MainActivity extends Activity implements OnClickListener {
Button btn, btn1;
SurfaceView sv;
Bitmap bitmap;
Canvas canvas;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn=(Button)findViewById(R.id.button1);
btn1=(Button)findViewById(R.id.button2);
sv=(SurfaceView)findViewById(R.id.surfaceView1);
btn.setOnClickListener(this);
btn1.setOnClickListener(this);
bitmap=BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
}
@Override
public void onClick(View v) {
canvas=sv.getHolder().lockCanvas();
if(canvas==null) return;
canvas.drawBitmap(bitmap, 100, 100, null);
sv.getHolder().unlockCanvasAndPost(canvas);
}
public boolean saveImageToInternalStorage(Bitmap image) {
try {
// Use the compress method on the Bitmap object to write image to
// the OutputStream
FileOutputStream fos = openFileOutput("desiredFilename.png", Context.MODE_PRIVATE);
// Writing the bitmap to the output stream
image.compress(Bitmap.CompressFormat.PNG, 100, fos);
fos.close();
return true;
} catch (Exception e) {
Log.e("saveToInternalStorage()", e.getMessage());
return false;
}
}
}
回答1:
To Save your bitmap in sdcard use the following code
Store Image
private void storeImage(Bitmap image) {
File pictureFile = getOutputMediaFile();
if (pictureFile == null) {
Log.d(TAG,
"Error creating media file, check storage permissions: ");// e.getMessage());
return;
}
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
image.compress(Bitmap.CompressFormat.PNG, 90, fos);
fos.close();
} catch (FileNotFoundException e) {
Log.d(TAG, "File not found: " + e.getMessage());
} catch (IOException e) {
Log.d(TAG, "Error accessing file: " + e.getMessage());
}
}
To Get the Path for Image Storage
/** Create a File for saving an image or video */
private File getOutputMediaFile(){
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
File mediaStorageDir = new File(Environment.getExternalStorageDirectory()
+ "/Android/data/"
+ getApplicationContext().getPackageName()
+ "/Files");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("ddMMyyyy_HHmm").format(new Date());
File mediaFile;
String mImageName="MI_"+ timeStamp +".jpg";
mediaFile = new File(mediaStorageDir.getPath() + File.separator + mImageName);
return mediaFile;
}
EDIT From Your comments i have edited the onclick view in this the button1 and button2 functions will be executed separately.
public onClick(View v){
switch(v.getId()){
case R.id.button1:
//Your button 1 function
break;
case R.id. button2:
//Your button 2 function
break;
}
}
回答2:
private static void SaveImage(Bitmap finalBitmap) {
String root = Environment.getExternalStorageDirectory().getAbsolutePath();
File myDir = new File(root + "/saved_images");
myDir.mkdirs();
String fname = "Image-"+ o +".jpg";
File file = new File (myDir, fname);
if (file.exists ()) file.delete ();
try {
FileOutputStream out = new FileOutputStream(file);
finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
回答3:
Modify onClick() as follows:
@Override
public void onClick(View v) {
if(v == btn) {
canvas=sv.getHolder().lockCanvas();
if(canvas!=null) {
canvas.drawBitmap(bitmap, 100, 100, null);
sv.getHolder().unlockCanvasAndPost(canvas);
}
} else if(v == btn1) {
saveBitmapToInternalStorage(bitmap);
}
}
There are several ways to enforce that btn must be pressed before btn1 so that the bitmap is painted before you attempt to save it.
I suggest that you initially disable btn1, and that you enable it when btn is clicked, like this:
if(v == btn) {
...
btn1.setEnabled(true);
}
回答4:
To save file into directory
public static Uri saveImageToInternalStorage(Context mContext, Bitmap bitmap){
String mTimeStamp = new SimpleDateFormat("ddMMyyyy_HHmm").format(new Date());
String mImageName = "snap_"+mTimeStamp+".jpg";
ContextWrapper wrapper = new ContextWrapper(mContext);
File file = wrapper.getDir("Images",MODE_PRIVATE);
file = new File(file, "snap_"+ mImageName+".jpg");
try{
OutputStream stream = null;
stream = new FileOutputStream(file);
bitmap.compress(Bitmap.CompressFormat.JPEG,100,stream);
stream.flush();
stream.close();
}catch (IOException e)
{
e.printStackTrace();
}
Uri mImageUri = Uri.parse(file.getAbsolutePath());
return mImageUri;
}
required permission
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
回答5:
You might be able to use the following for decoding, compressing and saving an image:
@Override
public void onClick(View view) {
onItemSelected1();
InputStream image_stream = null;
try {
image_stream = getContentResolver().openInputStream(myUri);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
Bitmap image= BitmapFactory.decodeStream(image_stream );
// path to sd card
File path=Environment.getExternalStorageDirectory();
//create a file
File dir=new File(path+"/ComDec/");
dir.mkdirs();
Date date=new Date();
File file=new File(dir,date+".jpg");
OutputStream out=null;
try{
out=new FileOutputStream(file);
image.compress(format,size,out);
out.flush();
out.close();
MediaStore.Images.Media.insertImage(getContentResolver(), image," yourTitle "," yourDescription");
image=null;
}
catch (IOException e)
{
e.printStackTrace();
}
Toast.makeText(SecondActivity.this,"Image Save Successfully",Toast.LENGTH_LONG).show();
}
});
来源：https://stackoverflow.com/questions/15662258/how-to-save-a-bitmap-on-internal-storage