如何使用Android中的按钮删除GridView中的多个图像? [英] How to delete multiple images in GridView using a button in Android?

问题描述

您好stackoverflow我正在尝试开发一个显示来自SD卡的图像并允许用户使用复选框删除图像的应用程序.我可以使用CheckBox从SD卡显示图像，但是无法删除用户动态勾选的特定图像.这是我的MainActivity.java

Hello stackoverflow I'm trying to develop an application that display images from SD card and allow user to delete the images using a check box. I'm able to display images from SD card with CheckBox but I'm unable to delete the specific image which has been ticked by the user dynamically. Here is my MainActivity.java

public class MainActivity extends Activity {
private int count;
private Bitmap[] thumbnails;
private boolean[] thumbnailsselection;
private String[] arrPath;
private ImageAdapter imageAdapter;
ArrayList<String> f = new ArrayList<String>();// list of file paths
File[] listFile;
Button btnDelete;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    getFromSdcard();
    GridView imagegrid = (GridView) findViewById(R.id.PhoneImageGrid);
    imageAdapter = new ImageAdapter();
    imagegrid.setAdapter(imageAdapter);

    imageAdapter.notifyDataSetChanged();

    btnDelete = (Button) findViewById(R.id.btnDeleteImg);

    btnDelete.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // to delete selected images

        }
    });
}

public void getFromSdcard() {
    File file = new File("/mnt/sdcard/Images");

    if (file.isDirectory()) {
        listFile = file.listFiles();

        for (int i = 0; i < listFile.length; i++) {

            f.add(listFile[i].getAbsolutePath());

        }
    }
}

public class ImageAdapter extends BaseAdapter {
    private LayoutInflater mInflater;

    public ImageAdapter() {
        mInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    public int getCount() {
        return f.size();
    }

    public Object getItem(int position) {
        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            convertView = mInflater.inflate(R.layout.galleryitem, null);
            holder.imageview = (ImageView) convertView
                    .findViewById(R.id.thumbImage);

            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        Bitmap myBitmap = BitmapFactory.decodeFile(f.get(position));
        holder.imageview.setImageBitmap(myBitmap);
        return convertView;
    }
}

class ViewHolder {
    ImageView imageview;
}

}

我的activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FFFFFF"
android:orientation="vertical" >

<GridView
    android:id="@+id/PhoneImageGrid"
    android:layout_width="fill_parent"
    android:layout_height="0dip"
    android:layout_weight="0.97"
    android:columnWidth="90sp"
    android:gravity="center"
    android:horizontalSpacing="10sp"
    android:numColumns="auto_fit"
    android:stretchMode="columnWidth"
    android:verticalSpacing="10sp" />

<RelativeLayout
    android:id="@+id/rlBookmark"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="#ffffff"
    android:layout_gravity="bottom" >

    <Button
        android:id="@+id/btnBookmark"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:text="Clear"
        android:textColor="#FF0011"
        android:textSize="15sp"
        android:textStyle="normal" />
</RelativeLayout>

</LinearLayout>

最后是我的galleryitem.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >

<ImageView
    android:id="@+id/thumbImage"
    android:layout_width="100sp"
    android:layout_height="100sp" />

<CheckBox
    android:id="@+id/itemCheckBox"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true" />

</RelativeLayout>

在此先感谢stackoverflow，请帮助我解决这个难题.

Please help me to solve this riddle, thanks in advance stackoverflow.

推荐答案

stackoverflow最后，我弄清楚了如何在GridView

Hi stackoverflow finally i figured out how to delete multiple images using CheckBox in a GridView

public class MainActivity extends Activity {
private int count;
private Bitmap[] thumbnails;
private boolean[] thumbnailsselection;
private String[] arrPath;
private ImageAdapter imageAdapter;
ArrayList<String> f = new ArrayList<String>();// list of file paths
File[] listFile;

Button btnDelete;

private ProgressDialog pd;

HashSet<String> selectedFile = new HashSet<String>();// list of file paths boolean checked

GridView imagegrid;

AlertDialog alertDialog = null;


@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getFromSdcard();
imagegrid = (GridView) findViewById(R.id.PhoneImageGrid);
imageAdapter = new ImageAdapter();
imagegrid.setAdapter(imageAdapter);

imageAdapter.notifyDataSetChanged();

btnDelete = (Button) findViewById(R.id.btnDeleteImg);

btnDelete.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
        // to delete selected images

    }
});
}

public void getFromSdcard() {
File file = new File("/mnt/sdcard/Images");

if (file.isDirectory()) {
    listFile = file.listFiles();

    for (int i = 0; i < listFile.length; i++) {

        f.add(listFile[i].getAbsolutePath());

    }
}
}

public class ImageAdapter extends BaseAdapter {
    private LayoutInflater mInflater;

    public ImageAdapter() {
        mInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    public int getCount() {
        return f.size();
    }

    public Object getItem(int position) {
        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            convertView = mInflater.inflate(R.layout.galleryitem, null);
            holder.imageview = (ImageView) convertView.findViewById(R.id.thumbImage);
            holder.checkbox = (CheckBox) convertView.findViewById(R.id.itemCheckBox);

            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        Bitmap myBitmap = BitmapFactory.decodeFile(f.get(position));
        holder.imageview.setImageBitmap(myBitmap);

        final int pos = position;

        holder.checkbox.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                if(!selectedFile.contains((String)f.get(pos)))
                {
                    selectedFile.add((String)f.get(pos));
                }
                else
                {
                    selectedFile.remove((String)f.get(pos));
                }
            }
        });
        return convertView;
    }
}

class ViewHolder {
    ImageView imageview;
    CheckBox checkbox;
    int id;
}
}

这种方法对我有用，如果你们需要更多信息，请发表评论，谢谢stackoverflow

This approach is working for me, if you guys need more information please comment, Thanks stackoverflow

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