Question

我是这个Android开发的新手。我想要做的是将ID从MainActivity传递给Details。因此，我需要从MainActivity获取ID，以便在Details课程中显示某个人的详细信息。我已经可以传递id并显示它，但是我无法显示来自数据库值的特定id的详细信息。如何使用数据库函数Details在getDetails(id);类中显示该特定id的内容？我需要在Details活动类的文本视图中显示它。请帮忙

数据库功能

public Cursor getDetails(String id) {
            return database.query(TABLENAME, null, id + "=" + id, null, null,
                    null, null);
        }

MainActivity.java

this.listView.setOnItemClickListener(new OnItemClickListener() {
                    @Override
                    public void onItemClick(AdapterView<?> arg0, View view, int position, long arg3){

                        TextView txtID = (TextView) view.findViewById(R.id.id);

                        String id = txtID.getText().toString();

                        Intent intent = new Intent(MainActivity.this, Details.class);
                        intent.putExtra("id", id);

                        startActivity(intent);
                    }
                });

在Details.java中，我想在此处显示数据库中ID的内容。我如何调用该函数并使用传递的意图中的ID进行显示？

Details.java

Intent i = getIntent();
String id = i.getStringExtra("id");

txtId = (TextView) findViewById(R.id.id);
txtName= (TextView) findViewById(R.id.name);
txtAbout = (TextView) findViewById(R.id.about);

txtId.setText(id);
txtName.setText(name);
txtAbout .setText(about);

Answer 1

public HashMap<String,String> getDetails(String id) {
    HashMap<String, String> hm = new HashMap<>();
    SQLiteDatabase db = getWritableDatabase();
    Cursor c = db.query(TABLENAME, null, "id=?", new String[]{id}, null, null, null);
    if(c.getCount()>0){
      c.moveToFirst();
      hm.put(KEY, c.getString(c.getColumnIndex(COLUMN_NAME)));
    // do this for all columns that you want.
    }
    c.close();
    db.close();
    return hm;
 }

并在Details.java中

String id = getIntent().getExtras.getString("id");
HashMap<String, String> hm = (Your database class Object).getDetails(id);
if(hm.size()>0){
  String value1 = hm.get(KEY);
// get all data and show according to you.
}

Android从意图值

1 个答案: