Android 在 MainActivity 中调用自定义适配器方法

Question

以下代码存在于我的主要活动中。我想知道它们是否是我可以使用传递给 gridview.setAdapter() 函数的 GridAdapter 实例调用方法的一种方式。

GridAdapter 负责用图像填充网格视图。单击时，我想获取它被单击的位置以及来自 GridAdapter 的一些数据。

    // create a new GridView object
    GridView gridview = this.findViewById(R.id.gridView);
    gridview.setAdapter(new GridAdapter(this));
    gridview.setOnItemClickListener(new AdapterView.OnItemClickListener()
    {
        @Override
        public void onItemClick(AdapterView<?> parent, View v,
                                int position, long id)
        {
            thisGridAdapter.someMethod(position);  //what I want to do
            Log.d("gridView", String.valueOf(position));
            TextView tv = findViewById(R.id.textView);
            tv.setText(String.valueOf(position));
        }
    });

Answer 1

将其分配给变量？

final GridAdapter adapter = new GridAdapter(this);
GridView gridView = findViewById(R.id.gridView);
gridView.setAdapter(adapter);
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
        adapter.someMethod(position);
    }
});

或者，使用GridView#getAdapter() 方法并将其转换为您的适配器类：

final GridView gridView = findViewById(R.id.gridView);
gridView.setAdapter(new GridAdapter(this));
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
        ((GridAdapter) gridView.getAdapter).someMethod(position);
    }
});