Question

我已成功设置 GridView ，但我希望能够根据变量更改 GridView 中的图像。例如：

int a = 2
if (a == 2){
    Integer[] images = {
        R.drawable.image1
        R.drawable.image3
    }
} else {
    Integer[] images = (
        R.drawable.image2
        R.drawable.image4
    }
}

但是我找不到办法做到这一点。我目前正在处理的代码是：

    GridView cardList = (GridView) findViewById(R.id.cardList);
    cardList.setAdapter(new ImageAdapter(this));

    cardList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                                int position, long id) {
            Toast.makeText(Create.this, "" + position,
                    Toast.LENGTH_SHORT).show();
        }
    });
}

public class ImageAdapter extends BaseAdapter {
    private Context mContext;

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

    public int getCount() {
        return images.length;
    }

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

    public long getItemId(int position) {
        return 0;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {
            // if it's not recycled, initialize some attributes
            imageView = new ImageView(mContext);
            imageView.setLayoutParams(new GridView.LayoutParams(215, 215));
        } else {
            imageView = (ImageView) convertView;
        }

        imageView.setImageResource(images[position]);
        return imageView;
    }

    private Integer[] images = {
            R.drawable.iamge1, R.drawable.image2
    };
}

Answer 1

尝试这样的事情：

活动：

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    GridView gridView = (GridView) findViewById(R.id.gridView);
    int images[] = {R.drawable.ic_action_name};
    ImageAdapter imageAdapter = new ImageAdapter(getApplicationContext(),images);
    gridView.setAdapter(imageAdapter);

    }
}

您的适配器类：

public class ImageAdapter extends BaseAdapter {
private int images[];
Context context;

public ImageAdapter(Context context, int images[]){

    this.context = context;
    this.images = images;
}

private class Holder{
    ImageView imageView;
}

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

@Override public Object getItem(int position){
    return null;
}

@Override
public long getItemId(int position){
    return 0;
}

@Override
public View getView(final int position, View view, ViewGroup parent){
    //All of this Holder stuff is so that the View doesn't jump around wildly

    final Holder holder;
    LayoutInflater inflater;

    if (view == null){
        inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.singleimage,null);
        holder = new Holder();
        holder.imageView = (ImageView) view.findViewById(R.id.singleImage);
        view.setTag(holder);
    }
    else {
        holder = (Holder) view.getTag();}

    holder.imageView.setImageResource(images[position]);

    return view;

}
}

您还需要一个简单的xml文件，用于gridView中的单个图像。将此命名为＆＃34; singleimage.xml＆＃34;

<?xml version="1.0" encoding="utf-8"?>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/singleImage"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>

活动xml文件：

<?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/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.ri.emily.testapp.MainActivity">    

    <GridView
        android:layout_width="match_parent"
        android:id="@+id/gridView"
        android:layout_height="match_parent" />
</RelativeLayout>

Android Studio动态更改GridView中的图像

1 个答案: