你不能在任何 Adapter 类中拥有这个，这只是 Activity 内部的一个方法，extends Activity 的每个类都可以覆盖这个方法，但肯定不是 Adapter。
请在java中查看Overrides
对于onActivityResult，请参阅Activity#onActivityResult(int, int, Intent)
对于像RecyclerView.Adapter 这样的东西，您需要在适配器中定义一个接口并在您的 Activity 中实现该接口。
例如，这里是一个应用程序的代码，它将一个被点击的项目及其位置的字符串发送到一个显示它的新活动：
主活动：
public class MainActivity extends AppCompatActivity implements MyAdapter.CallbackInterface {
private static final int MY_REQUEST = 1001;
private static final String [] ITEMS = {"Item 1", "Item 2", "Item 3" ,"Item 4", "Item 5", "Item 6"};
private MyAdapter myAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ... Adapter setup, simple LinearLayoutManager and String [] used
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.rec_view);
myAdapter = new MyAdapter(this, ITEMS);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(myAdapter);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch(resultCode){
case RESULT_OK:
// ... Check for some data from the intent
if(requestCode == MY_REQUEST){
// .. lets toast again
int position = -1;
if(data != null){
position = data.getIntExtra("Position", 0);
}
if(position != -1) {
Toast.makeText(this, "Handled the result successfully at position " + position, Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(this, "Failed to get data from intent" , Toast.LENGTH_SHORT).show();
}
}
break;
case RESULT_CANCELED:
// ... Handle this situation
break;
}
}
/**
* Interface Method which communicates to the Acitivty here from the {@link MyAdapter}
* @param position - the position
* @param text - the text to pass back
*/
@Override
public void onHandleSelection(int position, String text) {
Toast.makeText(this, "Selected item in list "+ position + " with text "+ text, Toast.LENGTH_SHORT).show();
// ... Start a new Activity here and pass the values
Intent secondActivity = new Intent(MainActivity.this, DetailActivity.class);
secondActivity.putExtra("Text",text);
secondActivity.putExtra("Position", position);
startActivityForResult(secondActivity, MY_REQUEST);
}
}
MainActivity 的xml：
<?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:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.divshark.recyclerviewsimpledemo.MainActivity">
<android.support.v7.widget.RecyclerView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/rec_view" />
</RelativeLayout>
我的适配器：
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyHolder>{
private CallbackInterface mCallback;
private String [] mMyItems;
private Context mContext;
public interface CallbackInterface{
/**
* Callback invoked when clicked
* @param position - the position
* @param text - the text to pass back
*/
void onHandleSelection(int position, String text);
}
public MyAdapter(Context context, String [] myItems){
mContext = context;
mMyItems = myItems;
// .. Attach the interface
try{
mCallback = (CallbackInterface) context;
}catch(ClassCastException ex){
//.. should log the error or throw and exception
Log.e("MyAdapter","Must implement the CallbackInterface in the Activity", ex);
}
}
@Override
public int getItemCount() {
return mMyItems.length;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public void onBindViewHolder(MyHolder holder, final int position) {
// Set the text for the View
holder.mTextView.setText(mMyItems[position]);
// Use your listener to pass back the data
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(mCallback != null){
mCallback.onHandleSelection(position, mMyItems[position]);
}
}
});
}
@Override
public MyHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.list_item, parent, false);
return new MyHolder(view);
}
static class MyHolder extends RecyclerView.ViewHolder{
TextView mTextView;
public MyHolder(View itemView) {
super(itemView);
mTextView = (TextView) itemView.findViewById(R.id.tv_list_item);
}
}
}
适配器的布局：
<?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:orientation="vertical" android:layout_width="match_parent"
android:layout_height="?listPreferredItemHeight">
<TextView
android:id="@+id/tv_list_item"
android:textColor="@android:color/black"
tools:text="Some Text Holder"
android:layout_marginLeft="16dp"
android:textSize="18sp"
android:layout_centerVertical="true"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</RelativeLayout>
和 DetailActivity：
public class DetailActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.detail_activity);
TextView textView = (TextView) findViewById(R.id.tv_detail_text);
if(getIntent() != null && getIntent().getExtras() != null) {
Bundle extras = getIntent().getExtras();
String text = extras.getString("Text");
int position = extras.getInt("Position");
textView.setText(String.format("%s at position %d", text, position));
// .. For this purpose set result okay and use position as part of data when Activity finishes
// Which will in turn invoke the onActivityResult method in the calling activity
Intent resultIntent = new Intent();
resultIntent.putExtra("Position", position);
setResult(RESULT_OK, resultIntent);
}
}
}
详细活动的布局：
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<TextView
android:id="@+id/tv_detail_text"
android:layout_gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</FrameLayout>
祝你好运，编码愉快！