gridview.setOnItemClickListener(newOnItemClickListener(){publicvoidonItemClick(AdapterViewparent,Viewv,intposition,longid){Toast.makeText(HelloGridView.this,""+position,Toast.LENGTH_SHORT).show();}}); 最佳答案 表示泛型。阅读更多关于他们的信息here.这里是documentation说的是参数:onItemClick(AdapterV

我有一个像这样的cart_layout:以及Cart.java中的java代码:protectedvoidonCreate(@NullableBundlesavedInstanceState){super.onCreate(savedInstanceState);setContentView(R.layout.cart_layout);getSupportActionBar().setDisplayShowTitleEnabled(false);getSupportActionBar().setDisplayHomeAsUpEnabled(true);dbhandler=newData