Question

我正在尝试从第二个活动到我的主要活动显示一个单词，该单词告知带有textview项目的回收者视图。

我已经创建了适配器，我认为它可以正常工作，唯一的问题是一旦启动浮动按钮访问显示字活动，它就不会显示在主要活动上，我在做什么错，我是新手Android。

我的适配器：

public class MainActivity extends AppCompatActivity {


    private  RoomAdapter roomAdapter;
    public static final int NEW_WORD_ACTIVITY_REQUEST_CODE = 1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        RecyclerView recyclerView = findViewById(R.id.rv_word);

        recyclerView.setAdapter(roomAdapter);
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(linearLayoutManager);

        FloatingActionButton floatingActionButton = findViewById(R.id.fab);
        floatingActionButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(getApplicationContext(), DisplayWord.class);
                String word = getIntent().getStringExtra(DisplayWord.EXTRA_KEY);
                startActivityForResult(intent,NEW_WORD_ACTIVITY_REQUEST_CODE);
            }
        });
    }



}

这是我的主要活动：

public class DisplayWord extends AppCompatActivity {

    public static final String EXTRA_KEY = "key";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_display_word);

        final EditText editText = findViewById(R.id.word_edit_text);
        Button button = findViewById(R.id.word_button);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent replyIntent = new Intent();
                if(TextUtils.isEmpty(editText.getText())){
                    setResult(RESULT_CANCELED, replyIntent);
                }else {
                String word = editText.getText().toString();
                replyIntent.putExtra(EXTRA_KEY,word);


                }

                finish();
            }
        });


    }
}

这是我的显示字，它带有一个按钮和一个只应包含一个字符串的编辑文本。

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rv_word"
        android:layout_width="368dp"
        android:layout_height="433dp"
        android:layout_marginLeft="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_marginLeft="328dp"
        android:layout_marginStart="328dp"
        android:layout_marginTop="12dp"
        android:src="@drawable/ic_add_black_24dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/rv_word" />
</android.support.constraint.ConstraintLayout>

Main.xml

url <- "https://fasttrack.grv.org.au/Dog/Form?id=2003010003" 
tab <- url %>% read_html %>%  
  html_node("dogruns_wrapper") %>%  
  html_text()    
View(tab)

Answer 1

您的代码应如下所示：

       button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent replyIntent = new Intent();
            if(TextUtils.isEmpty(editText.getText())){
                setResult(RESULT_CANCELED, replyIntent);
            }else {
            String word = editText.getText().toString();
            replyIntent.putExtra(EXTRA_KEY,word);
            setResult(RESULT_OK, replyIntent); //missing
            }

            finish();
        }
    });

然后在MainActivity.java中处理它

    @Override
      protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    try {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == REQUEST_CODE  && resultCode  == RESULT_OK) {

            String requiredValue = data.getStringExtra(DisplayWord.EXTRA_KEY);
        }
    } catch (Exception ex) {
        Toast.makeText(Activity.this, ex.toString(),
                Toast.LENGTH_SHORT).show();
    }

}

在第二个活动的recyclerview中显示单词

1 个答案: