图像适配器未显示在网格视图中

Question

我正在尝试以网格视图的形式设置图像，但我看不到任何图像。我希望它们在活动的缩略图视图中。如何在两列的网格视图中显示图像：

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/activity_fit_employess"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin">

    <GridView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:numColumns="2"
        android:id="@+id/admin_homepage_grid"
        />
</LinearLayout>

这是我的图像适配器类

public class ImageAdapter extends BaseAdapter {

int[] icons={ R.mipmap.new_admissions,R.mipmap.inbox,R.mipmap.courses,R.mipmap.parent,R.mipmap.teacher
};
    private Context context;
    public ImageAdapter(Context c)
    {
        context = c;
    }
    @Override
    public int getCount() {
        return 0;
    }
    @Override
    public Object getItem(int position) {
        return null;
    }
    @Override
    public long getItemId(int position) {
        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(600,600));
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            imageView.setPadding(5,5,5,5);
        }
        else{
            imageView=(ImageView)convertView;
        }
        imageView.setImageResource(icons[position]);
        return imageView;
    }

}

这是我的活动课

 public class LibAdminHomepage extends AppCompatActivity {
GridView gv;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_lib_admin_homepage);
    gv=(GridView)findViewById(R.id.admin_homepage_grid);
    gv.setAdapter(new ImageAdapter(this));
    gv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            switch (position){
                case 0:
                    Toast.makeText(LibAdminHomepage.this,""+position,Toast.LENGTH_SHORT).show();
                    break;
                case 1:
                    Toast.makeText(LibAdminHomepage.this,""+position,Toast.LENGTH_SHORT).show();
                    break;
                case 2:
                    Toast.makeText(LibAdminHomepage.this,""+position,Toast.LENGTH_SHORT).show();
                    break;
                case 3:
                    Toast.makeText(LibAdminHomepage.this,""+position,Toast.LENGTH_SHORT).show();
                    break;
                case 4:
                    Toast.makeText(LibAdminHomepage.this,""+position,Toast.LENGTH_SHORT).show();
                    break;
            }
        }
    });

}

}

Answer 1

只需用这个替换你的适配器getCount()方法，你就会得到图像

@Override
public int getCount() {
    return icons.length;
}

Answer 2

您在适配器getCount上返回 0

试试这段代码：

 public class ImageAdapter extends BaseAdapter {

int[] icons={ R.mipmap.new_admissions,R.mipmap.inbox,R.mipmap.courses,R.mipmap.parent,R.mipmap.teacher
}; 
    private Context context;
    public ImageAdapter(Context c)
    { 
        context = c;
    } 
    @Override 
    public int getCount() { 
        return icons.length; 
    } 
    @Override 
    public Object getItem(int position) {
        return icons[position]; 
    } 
    @Override 
    public long getItemId(int position) {
        return position; 
    } 
    @Override 
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if(convertView==null)
        { 
            imageView=new ImageView(context);
            imageView.setLayoutParams(new GridView.LayoutParams(600,600));
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            imageView.setPadding(5,5,5,5);
        } 
        else{ 
            imageView=(ImageView)convertView;
        } 
        imageView.setImageResource(icons[position]);
        return imageView;
    }