应用程序关闭后，我试图在imagebutton中重新加载从图库或相机中获取的图像
我尝试将其保存到文件中并从该文件加载，但是我无法使其正常工作。
public class HomeFragment extends Fragment {
ImageButton profilePic;
Drawable myDrawable;
Bitmap bitmap ;
String photoPath = Environment.getExternalStorageDirectory().toString();
public View onCreateView(@NonNull LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_home,container,false);
profilePic = (ImageButton) root.findViewById(R.id.imageButton);
myDrawable = profilePic.getBackground();
bitmap = drawableToBitmap(myDrawable);
// set up listener on ImageButton to load method changeProfilePicture() when user clicks profilePic
profilePic.setOnClicklistener(new View.OnClicklistener() {
public void onClick(View v) {
changeProfilePicture();
}
});
int Permission_All = 1;
String[] Permissions = {Manifest.permission.READ_EXTERNAL_STORAGE,Manifest.permission.WRITE_EXTERNAL_STORAGE};
if(!hasPermissions(getactivity(),Permissions)){
activityCompat.requestPermissions(getactivity(),Permissions,Permission_All);
}
loadImageFromStorage(photoPath);
return root;
}
public void onResume() {
super.onResume();
loadImageFromStorage(photoPath);
}
public void onStart() {
super.onStart();
}
public void onPause() {
super.onPause();
}
public void onStop() {
super.onStop();
saveBitmap(bitmap);
}
public void onDestroy() {
super.onDestroy();
}
static final int REQUEST_IMAGE_CAPTURE = 1;
static final int REQUEST_GALLERY = 0;
//create changeProfilePicture method and call it when the ImageButton is pressed
public void changeProfilePicture() {
// add alert dialog to ask user how they would like to change their profile icon
}
// override onactivityResult to allow the imageButton to be changed to picture taken from camera or gallery
public void onactivityResult(int requestCode,int resultCode,Intent data) {
super.onactivityResult(requestCode,resultCode,data);
if(resultCode == RESULT_OK) {
//create a switch based on requestCode
switch (requestCode) {
// if user clicks change profilePic through gallery use picture user picked from gallery
case REQUEST_GALLERY:
Uri galleryImage = data.getData();
try {
Bitmap galleryBitmap = MediaStore.Images.Media.getBitmap(getactivity().getcontentResolver(),galleryImage);
galleryBitmap = Bitmap.createScaledBitmap(galleryBitmap,200,false);
profilePic.setImageBitmap(galleryBitmap);
saveBitmap(galleryBitmap);
} catch (IOException e) {
Log.i("TAG","Exception " + e);
}
break;
// if user clicks change profilePic through camera use picture user took from camera app
case REQUEST_IMAGE_CAPTURE:
Bundle extras = data.getExtras();
Bitmap imageBitmap = (Bitmap) extras.get("data");
imageBitmap = Bitmap.createScaledBitmap(imageBitmap,false);
profilePic.setImageBitmap(imageBitmap);
saveBitmap(imageBitmap);
break;
}
}
}
private void saveBitmap(Bitmap bm){
File file = Environment.getExternalStorageDirectory();
File newFile = new File(file,"myImage.jpg");
try {
FileOutputStream fileOutputStream = new FileOutputStream(newFile);
bm.compress(Bitmap.CompressFormat.JPEG,100,fileOutputStream);
fileOutputStream.flush();
fileOutputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Log.i( "getExternalStorageDirectory",file.getPath()) ;
}
private void loadImageFromStorage(String path)
{
try {
File f=new File(path,"myImage.jpg");
Bitmap b = BitmapFactory.decodeStream(new FileInputStream(f));
profilePic.setImageBitmap(b);
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
}
public static Bitmap drawableToBitmap (Drawable drawable) {
Bitmap bitmap = null;
if (drawable instanceof BitmapDrawable) {
BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
if(bitmapDrawable.getBitmap() != null) {
return bitmapDrawable.getBitmap();
}
}
if(drawable.getIntrinsicWidth() <= 0 || drawable.getIntrinsicHeight() <= 0) {
bitmap = Bitmap.createBitmap(1,1,Bitmap.Config.ARGB_8888);
} else {
bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),drawable.getIntrinsicHeight(),Bitmap.Config.ARGB_8888);
}
Canvas canvas = new Canvas(bitmap);
drawable.setbounds(0,canvas.getWidth(),canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}
public static boolean hasPermissions(Context context,String... permissions)
{
if(Build.VERSION.SDK_INT>= Build.VERSION_CODES.M && context!=null && permissions!=null){
for(String permission: permissions){
if(activityCompat.checkSelfPermission(context,permission)!= PackageManager.PERMISSION_GRANTED){
return false;
}
}
}
return true;
}
}
// what I have for my ImageButton in xml
<ImageButton
android:id="@+id/imageButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:contentDescription="@string/profilePic"
android:onClick="changeProfilePicture"
android:paddingLeft="0dp"
android:paddingTop="0dp"
android:paddingRight="0dp"
android:paddingBottom="0dp"
android:layout_marginTop="2dp"
android:layout_marginBottom="5dp"
android:background="#0000"
app:srcCompat="@mipmap/ic_launcher_round" />
I have the following permissions inside the manifest.xml
<uses-feature
android:name="android.hardware.camera"
android:required="true" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
我正在尝试从结果中保存新的ImageButton并在重新启动应用程序时加载它。可以使用ImageButton完成吗？可以将其保存到文件并从中加载吗？