android - 删除图像后自动刷新在 gridview 中不起作用

Question

我正在研究 GridView ，我是 android 的新手。我以前在 gridview 中遇到问题，我自己解决了我发布链接是因为代码是相同的，除了上下文任务中添加的新功能 i dont know how to get the position of the img that i click so i can pass it to next acitvity剩下的代码如下

@Override  
public boolean onContextItemSelected(MenuItem item) {  
    if(item.getTitle()=="View"){function1(item.getItemId());}  
    else if(item.getTitle()=="Details"){function2(item.getItemId());}  
    else if(item.getTitle()=="Delete"){function3(item.getItemId());}  
    else {return false;}  
    return true;  
}  

public void function1(int id){ 


    //String prompt;
    // Sending image id to FullScreenActivity

    /*Toast.makeText(getApplicationContext(), 
                path, 
                Toast.LENGTH_LONG).show();*/
    Intent i = new Intent(getApplicationContext(), FullImageActivity.class);
    i.putExtra("id", path );
    startActivity(i);
}  
public void function2(int id){  
    Toast.makeText(this, "Details func called", Toast.LENGTH_SHORT).show();  
} 
public void function3(int id){  
    File file = new File(path);
    if(file.exists())
    {
        boolean deleted = file.delete();
    }
    myImageAdapter.notifyDataSetChanged();

    //adapter.notifyDataSetChanged();

    //gv.invalidateViews();


    Toast.makeText(this, "function delete called", Toast.LENGTH_SHORT).show();  
} 

我不允许发布图像，因为我的声誉较低，但是当调用删除函数时图像被删除但 GridView 中有一个空白空间我希望在调用删除函数后自动填充空白空间.

Answer 1

您需要从适配器中的图像列表中删除该文件。否则，文件路径仍在列表中，因此将尝试加载图像并失败，从而导致空白。

public class ImageAdapter extends BaseAdapter {
    private Context mContext;
    ArrayList<String> itemList = new ArrayList<String>();

    public ImageAdapter(Context c) {
        mContext = c;   
    }

    void add(String path){
        itemList.add(path); 
    }

    void remove(String path){
        itemList.remove(path);
    }
}

public void function3(int id){  
    File file = new File(path);
    if(file.exists())
    {
        boolean deleted = file.delete();
    }
    myImageAdapter.remove(path);
    myImageAdapter.notifyDataSetChanged();

    Toast.makeText(this, "function delete called", Toast.LENGTH_SHORT).show();  
}