问题
The GridView is already being populated by the contents of a specific folder called "MyDir". My layout gallery_fragment is split in half by two linearlayouts. The one on the left has the GridView which is already populated with the images from "MyDir". The layout on the right has an ImageView.
The idea is that I can select an image from the GridView on the left and then it will appear on the ImageView on the right. I cannot use the res/drawables folder in this instance.
I have been told I will need to use a HashMap hMap; Does anybody have any suggestions?
public class GalleryFragment4 extends Fragment {
private ImageView imageView;
private ImageGridViewAdapter imageAdapter;
private GridView gridView;
private static final String GRIDVIEW_TAG = "Android Logo";
@SuppressLint("UseSparseArrays")
public HashMap<Integer, String> hMap = new HashMap<Integer, String>();
// private LinearLayout linear;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_gallery, container,
false);
// assigns gridView to an object
gridView = (GridView) rootView.findViewById(R.id.gridview);
gridArchitecture(rootView);
extractFiles();
/**
* GridView is waiting for an image to be selected
*/
gridView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// image number
int num = (position + 1);
// When image is selected show image number
Toast.makeText(getActivity().getApplicationContext(),
"image : " + num, Toast.LENGTH_SHORT).show();
((Context) getCameraImages(getActivity())).getApplicationContext();
try{
imageView.setImageResource(position);
}catch(NullPointerException ex){
}
}
});
return rootView;
}
/*
* Save image to external SD card and create new file if said file is not
* already created
*/
public static final String DIRECTORY_PATH = Environment
.getExternalStorageDirectory().toString() + "/MyDir/";
// public static final String CAMER_IMAGE_BUCKET_ID = getBucketId(DIRECTORY_PATH);
/**
* Matches code in MediaProvider.computeBucketValues. Should be a common
* function.
*/
// public static String getBucketId(String path) {
// return String.valueOf(path.toLowerCase().hashCode());
// }
/**
* Retrieve all camera images
*
* @param context
* @return
*/
public static List<String> getCameraImages(Context context) {
final String[] projection = { MediaStore.Images.Media.DATA };
final String selection = MediaStore.Images.Media.BUCKET_ID + " = ?";
final String[] selectionArgs = { DIRECTORY_PATH };
final Cursor cursor = context.getContentResolver().query(
Images.Media.EXTERNAL_CONTENT_URI, projection, selection,
selectionArgs, null);
ArrayList<String> result = new ArrayList<String>(cursor.getCount());
if (cursor.moveToFirst()) {
final int dataColumn = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
do {
final String data = cursor.getString(dataColumn);
result.add(data);
} while (cursor.moveToNext());
}
cursor.close();
return result;
}
private void extractFiles() {
// Name of the folder
final String targetPath = DIRECTORY_PATH;
// Toast showing name of directory which images are saved to.
Toast.makeText(getActivity().getApplicationContext(), targetPath,
Toast.LENGTH_LONG).show();
File targetDirector = new File(targetPath);
final File[] files = targetDirector.listFiles();
for (File file : files) {
imageAdapter.add(file.getAbsolutePath());
}
}
private void gridArchitecture(View rootView) {
// Sets the Tag
gridView.setTag(GRIDVIEW_TAG);
/*
* Adapt the image for the GridView format
*/
imageAdapter = new ImageGridViewAdapter(getActivity()
.getApplicationContext());
gridView.setAdapter(imageAdapter);
// Set the orientation to landscape
getActivity().setRequestedOrientation(
ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
}
}
If of any use here is the ImageGridviewAdapter.java
public class ImageGridViewAdapter extends BaseAdapter {
private Context context;
ArrayList<String> imageList = new ArrayList<String>();
public ImageGridViewAdapter(Context c) {
context = c;
}
void add(String path){
imageList.add(path);
}
@Override
public int getCount() {
return imageList.size();
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
imageView = new ImageView(context);
imageView.setLayoutParams(new GridView.LayoutParams(220, 220));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
//8,8,8,8
imageView.setPadding(20, 20, 20, 20);
} else {
imageView = (ImageView) convertView;
}
// 200, 200
Bitmap bm = decodeSampledBitmapFromUri(imageList.get(position), 100, 100);
imageView.setImageBitmap(bm);
return imageView;
}
public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {
Bitmap bm = null;
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(path, options);
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
options.inJustDecodeBounds = false;
bm = BitmapFactory.decodeFile(path, options);
return bm;
}
public int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
if (width > height) {
inSampleSize = Math.round((float)height / (float)reqHeight);
} else {
inSampleSize = Math.round((float)width / (float)reqWidth);
}
}
return inSampleSize;
}
}
Here is the xml fragment_gallery.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/top"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/darkblue"
android:orientation="horizontal" >
<LinearLayout
android:id="@+id/center_point"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_centerInParent="true"
android:orientation="horizontal" />
<LinearLayout
android:id="@+id/right_linear"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_toRightOf="@+id/center_point"
android:background="@drawable/normal_shape" >
<ImageView
android:id="@+id/imageView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_marginBottom="320dp"
android:contentDescription="@drawable/android_icon"
android:src="@drawable/android_icon" />
</LinearLayout>
<LinearLayout
android:id="@+id/left_linear"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignRight="@+id/center_point" >
<GridView
android:id="@+id/gridview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:columnWidth="50dp"
android:gravity="center"
android:horizontalSpacing="10dip"
android:numColumns="2"
android:stretchMode="columnWidth"
android:verticalSpacing="10dip" >
</GridView>
</LinearLayout>
</RelativeLayout>
回答1:
Assuming that your target ImageView is declared as:
private ImageView targetImageView;
All you need to do is register the listener like below to your gridView:
gridView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// You know that the convertView returned from your adapter's
// getView method is ImageView so you can cast it here accordingly.
targetImageView.setImageDrawable(((ImageView) view).getDrawable());
}
});
回答2:
Just Check i have changed your file look and Compare and make change accordingly 1).GalleryFragment4.java
public class GalleryFragment4 extends Fragment {
private ImageView imageView;
private ImageGridViewAdapter imageAdapter;
private GridView gridView;
private static final String GRIDVIEW_TAG = "Android Logo";
// Change is here
ArrayList<String> imageList = new ArrayList<String>();
@SuppressLint("UseSparseArrays")
public HashMap<Integer, String> hMap = new HashMap<Integer, String>();
// private LinearLayout linear;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_gallery, container,
false);
// assigns gridView to an object
gridView = (GridView) rootView.findViewById(R.id.gridview);
imageview = (ImageView) rootview.findviewById(//Place_id);
gridArchitecture(rootView);
extractFiles();
/**
* GridView is waiting for an image to be selected
*/
gridView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// image number
//int num = (position + 1);
// When image is selected show image number
//Toast.makeText(getActivity().getApplicationContext(),
// "image : " + num, Toast.LENGTH_SHORT).show();
Bitmap bm = decodeSampledBitmapFromUri(imageList.get(position), 100, 100);
imageView.setImageBitmap(bm);
});
return rootView;
}
public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {
Bitmap bm = null;
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(path, options);
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
options.inJustDecodeBounds = false;
bm = BitmapFactory.decodeFile(path, options);
return bm;
}
public int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
if (width > height) {
inSampleSize = Math.round((float)height / (float)reqHeight);
} else {
inSampleSize = Math.round((float)width / (float)reqWidth);
}
}
return inSampleSize;
}
/*
* Save image to external SD card and create new file if said file is not
* already created
*/
public static final String DIRECTORY_PATH = Environment
.getExternalStorageDirectory().toString() + "/MyDir/";
// public static final String CAMER_IMAGE_BUCKET_ID = getBucketId(DIRECTORY_PATH);
/**
* Matches code in MediaProvider.computeBucketValues. Should be a common
* function.
*/
// public static String getBucketId(String path) {
// return String.valueOf(path.toLowerCase().hashCode());
// }
/**
* Retrieve all camera images
*
* @param context
* @return
*/
public static List<String> getCameraImages(Context context) {
final String[] projection = { MediaStore.Images.Media.DATA };
final String selection = MediaStore.Images.Media.BUCKET_ID + " = ?";
final String[] selectionArgs = { DIRECTORY_PATH };
final Cursor cursor = context.getContentResolver().query(
Images.Media.EXTERNAL_CONTENT_URI, projection, selection,
selectionArgs, null);
ArrayList<String> result = new ArrayList<String>(cursor.getCount());
if (cursor.moveToFirst()) {
final int dataColumn = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
do {
final String data = cursor.getString(dataColumn);
result.add(data);
} while (cursor.moveToNext());
}
cursor.close();
return result;
}
private void extractFiles() {
// Name of the folder
final String targetPath = DIRECTORY_PATH;
// Toast showing name of directory which images are saved to.
Toast.makeText(getActivity().getApplicationContext(), targetPath,
Toast.LENGTH_LONG).show();
File targetDirector = new File(targetPath);
final File[] files = targetDirector.listFiles();
for (File file : files) {
//change is here
imageList.add(file.getAbsolutePath());
}
}
private void gridArchitecture(View rootView) {
// Sets the Tag
gridView.setTag(GRIDVIEW_TAG);
/*
* Adapt the image for the GridView format
*/
// change is here.
imageAdapter = new ImageGridViewAdapter(getActivity()
.getApplicationContext(),imageList);
gridView.setAdapter(imageAdapter);
// Set the orientation to landscape
getActivity().setRequestedOrientation(
ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
}
}
2.ImageGridviewAdapter.java
public class ImageGridViewAdapter extends BaseAdapter {
private Context context;
ArrayList<String> imageList = new ArrayList<String>();
public ImageGridViewAdapter(Context c,ArrayList<String> imageLists) {
context = c;
imageList = imageLists;
}
//Change is here
// void add(String path){
// imageList.add(path);
// }
@Override
public int getCount() {
return imageList.size();
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
imageView = new ImageView(context);
imageView.setLayoutParams(new GridView.LayoutParams(220, 220));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
//8,8,8,8
imageView.setPadding(20, 20, 20, 20);
} else {
imageView = (ImageView) convertView;
}
// 200, 200
Bitmap bm = decodeSampledBitmapFromUri(imageList.get(position), 100, 100);
imageView.setImageBitmap(bm);
return imageView;
}
public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {
Bitmap bm = null;
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(path, options);
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
options.inJustDecodeBounds = false;
bm = BitmapFactory.decodeFile(path, options);
return bm;
}
public int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
if (width > height) {
inSampleSize = Math.round((float)height / (float)reqHeight);
} else {
inSampleSize = Math.round((float)width / (float)reqWidth);
}
}
return inSampleSize;
}
}
i have write where i have made changes if still found any error then comment bellow
来源：https://stackoverflow.com/questions/25360036/onclickitem-in-gridview-how-do-i-show-the-same-image-in-a-separate-imageview