Question

我正在创建一个应用程序，其中有一个活动从另一个活动发送到另一个活动。我正在使用其他ArrayAdapters。我已经创建了一个包含我需要的参数的容器，但是当我在Activity中编写它时，它不起作用，因为它期望别的东西比我写的东西。我从一个活动发送到另一个活动的数据是来自用户的输入。我正在使用输入来过滤我制作的ListView。所以我的问题是，如何修复构造函数，以便它可以使用我需要的参数？我知道我上传了很多代码，但我认为这是相关的。

这是我的容器：

public class Container{
public final String søgeord;
public final String itemname;
public final Integer imgid;
Container(String søgeord, String itemname, Integer imgid){
    this.søgeord=søgeord;
    this.itemname = itemname;
    this.imgid = imgid;
 }
}

这是CustomListAdapter：

public class CustomListAdapter extends ArrayAdapter<Container>{

private final Activity context;
LayoutInflater inflater;

    public CustomListAdapter(Activity context, Container[] containers) {
        super(context, R.layout.mylist, containers);
        this.context=context;
    }
public View getView(int position,View view,ViewGroup parent) {
    inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    view = inflater.inflate(R.layout.mylist, null);

    TextView txtTitle = (TextView) view.findViewById(R.id.item);
    ImageView imageView = (ImageView) view.findViewById(R.id.icon);
    TextView extratxt = (TextView) view.findViewById(R.id.textView1);

    Container currentItem = getItem(position);

    txtTitle.setText(currentItem.itemname);
    imageView.setImageResource(currentItem.imgid);
    extratxt.setText(currentItem.itemname);
    return view;

 };
}

这是我发送数据的活动，并在构造函数旁边注释：

public class Forside extends AppCompatActivity implements View.OnClickListener, Liste{

CustomListAdapter listAdapter;
EditText filterText;

ImageButton sog;
EditText sogefelt;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_forside);

    filterText = (EditText)findViewById(R.id.sogefelt);
    ListView itemList = (ListView)findViewById(R.id.listView);

    listAdapter = new CustomListAdapter (this, annoncer, imageId, null); //this is the constructor
    sog = (ImageButton) findViewById(R.id.sog);
    sog.setOnClickListener(this);
    sogefelt = (EditText) findViewById(R.id.sogefelt);

    itemList.setAdapter(listAdapter);
    itemList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            if (position==0){
                Intent intent = new Intent(Forside.this, Sogeresultater.class);
                startActivity(intent);
            }
        }
    });

}

public void onClick (View v){
    if (v == sog){
        String søgeord = sogefelt.getText().toString();
        ArrayList<String> resultater = new ArrayList<String>();
        for(String i: annoncer) {
            if (i.toUpperCase().contains(søgeord.toUpperCase()))
                resultater.add(i);
        }
        Intent intent = new Intent(this, Sogeresultater.class);
        intent.putExtra("søg", resultater.toArray(new String[resultater.size()]));
        startActivity(intent);
    }

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {

    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}


@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();
    if (id == R.id.Forside) {
        Intent intent = new Intent(this, Forside.class);
        startActivity(intent);
    }
    else if (id == R.id.Logind){
        Intent intent = new Intent(this, Log_Ind.class);
        startActivity(intent);
    }
    else if (id==R.id.Opretbruger) {
        Intent intent = new Intent(this, Opret_bruger.class);
        startActivity(intent);
    }
    return true;
 }
}

最后但并非最不重要的，这是我将数据发送到的活动：

public class Sogeresultater extends AppCompatActivity implements Liste{

CustomListAdapter listAdapter;
EditText filterText;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_list);


    final String[] søgestreng = getIntent().getExtras().getStringArray("søg");


    filterText = (EditText)findViewById(R.id.sogefelt);
    ListView itemList = (ListView)findViewById(R.id.listView);
    listAdapter = new CustomListAdapter (this, annoncer, imageId, søgestreng); //this also the constructor, here I want "søgestreng", as it's the input from the user

    itemList.setAdapter(listAdapter);
    itemList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Toast.makeText(getApplicationContext(), "Position " + position, Toast.LENGTH_LONG).show();
        }
    });

    filterText.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            Sogeresultater.this.listAdapter.getFilter().filter(s);
        }

        @Override
        public void afterTextChanged(Editable s) {

        }
    });
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {

    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}


@Override
public boolean onOptionsItemSelected(MenuItem item) {

    int id = item.getItemId();


    if (id == R.id.Forside) {
        return true;
    }

    return super.onOptionsItemSelected(item);
 }
}

Answer 1

CustomListAdapter只能处理Container个数组。每个容器似乎都有您尝试提供给适配器构造函数的属性。

要使其正常工作，您需要将所拥有的数据转换为所需的格式:(即将String[]数组转换为Container[]数组）

List<Container> containers = new ArrayList<Container>();
for (String sogething : søgestreng) {
    String itemname = "I don't know"; // ?
    Integer imgid = 1234; // ?
    Container container = new Container(sogething, itemname, imgid);
    containers.add(container);
}
Container[] array = containers.toArray(new Container[containers.size()]);
listAdapter = new CustomListAdapter(this, array);

或者您需要更改现有/添加另一个对String[]数组而不是完整Container数组感到满意的构造函数。但是，由于您的适配器需要Container中定义的内容，因此您必须想出一种方法来替换/加载属于该字符串的数据。

如何修复构造函数以使其与我想要的参数一起使用？

1 个答案: