我可以知道为什么我的自定义 ListView 适配器看起来像这样吗？

图片:

代码:

MainActivity.java

public class MainActivity extends AppCompatActivity {

CurrencyRatesDetails crd = new CurrencyRatesDetails();

TextView inputCurrTV, convertedAmtTV;
ListView currencyLV;
EditText inputAmtET;
ArrayAdapter<String> adapter;
String[] currNameArr = crd.getNames();
String[] currCodeArr = crd.getCodes();
String[] currRateArr = crd.getRates();

Context context;

int index = 0;

//String[] rateCurrArr = {"AUD", "BGN", "BRL", "CAD", "CHF", "CNY"};
//double[] rateArr = {0.944, 1.2824, 2.2842, 0.96158, 0.70946, 4.8624}
Menu myMenu = null;

double rate, amtInput, finalConversion;

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

    context = this;

    inputAmtET = (EditText) findViewById(R.id.inputAmtET);
    convertedAmtTV = (TextView) findViewById(R.id.convertedAmtTV);
    inputCurrTV = (TextView) findViewById(R.id.inputCurrTV);
    currencyLV = (ListView) findViewById(R.id.currencyLV);

    //Resources myRes = this.getResources();
    //currArr =  myRes.getStringArray(R.array.currencyList);
    //adapter = ArrayAdapter.createFromResource(this, R.array.currencyList, android.R.layout.simple_selectable_list_item);
    //adapter = new ArrayAdapter<String>(this, android.R.layout.simple_selectable_list_item, currNameArr);
    //currencyLV.setAdapter(adapter);

    currencyLV.setAdapter(new CustomAdapterLV(this, currNameArr, currCodeArr, currRateArr));

    currencyLV.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

            inputCurrTV.setText(currCodeArr[i]);

            index = i;

            //Getting rate based on selected currency code
            //rate = rateArr[i];

        }
    });
}

public boolean onCreateOptionsMenu(Menu menu) {
    super.onCreateOptionsMenu(menu);
    this.myMenu = menu;
    addMenuItems(menu);

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

private void addMenuItems(Menu menu) {
    int index = 200;
    menu.add(index, index, index, "Settings");
    menu.add(index, index + 1, index + 1, "Add Custom Rate");
    menu.add(index, index + 2, index + 2, "Load Default Rates");
}

public boolean onOptionsItemSelected(MenuItem item) {

    //getOrder() to get Menu Item at this specific orderId
    if (item.getOrder() == 123) {

        amtInput = Double.parseDouble(inputAmtET.getText().toString());

        //finalConversion = amtInput / rate;

        finalConversion = crd.conversion(amtInput, index);

        //Formatting converted value to 2d.p
        String finalValue = String.format("%.2f", finalConversion);

        convertedAmtTV.setText(finalValue);

    } else if (item.getItemId() == 201) {

        Intent myIntent = new Intent(MainActivity.this, CustomXchangeRate.class);
        startActivity(myIntent);

    }

    return true;
}

Custom LV Adapter Layout.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_custom_lvadapter"
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"
android:weightSum="1"
android:orientation="vertical">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="0.0dp"
    android:weightSum="1"
    android:layout_weight="0.13"
    android:orientation="horizontal" >

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="0.7"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/currencyNameTV"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="15dp"
            android:text="text"/>

        <TextView
            android:id="@+id/currencyCodeTV"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="15px"
            android:textSize="18dp"
            android:text="text"/>

    </LinearLayout>

    <LinearLayout
        android:layout_width="0.0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.3"
        android:orientation="vertical"
        android:layout_gravity="center_horizontal" >

        <TextView
            android:id="@+id/currencyRateTV"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="text"
            android:textSize="30dp"
            android:layout_marginLeft="15px"
            android:layout_marginTop="15px"
            android:gravity="center_horizontal" />

    </LinearLayout>

</LinearLayout>

自定义 LV 适配器 Class.java

public class CustomAdapterLV extends BaseAdapter{

String[] resultNames;
String[] resultCodes;
String[] resultRates;

Context context;

private static LayoutInflater inflater = null;

public CustomAdapterLV(MainActivity mainActivity, String[] names,          String[]codes, String[] rates) {
    resultNames = names;
    resultCodes = codes;
    resultRates = rates;

    context = mainActivity;

    inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

}

@Override
public int getCount() {
    return resultNames.length;
}

@Override
public Object getItem(int position) {
    return position;
}

@Override
public long getItemId(int position) {
    return position;
}

public class ViewHolder{
    TextView tvName;
    TextView tvCode;
    TextView tvRate;
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    ViewHolder vh = new ViewHolder();
    View rowView;

    rowView = inflater.inflate(R.layout.activity_custom_lvadapter, null);

    vh.tvName = (TextView) rowView.findViewById(R.id.currencyNameTV);
    vh.tvCode = (TextView) rowView.findViewById(R.id.currencyCodeTV);
    vh.tvRate = (TextView) rowView.findViewById(R.id.currencyRateTV);

    vh.tvName.setText(resultNames[position]);
    vh.tvCode.setText(resultCodes[position]);
    vh.tvRate.setText(resultRates[position]);

    return rowView;

}

currNameArr、currCodeArr、currRateArr 硬编码在另一个类中，似乎无法添加。

谢谢各位..

最佳答案

我试了一下，我没有编辑器，所以请给我反馈。

尝试使用这种布局:您的 TextView 可能小于文本的高度

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_custom_lvadapter"
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"

android:orientation="vertical">
<!-- I removed the weightsum because this linearlayout is containing only a single item. If you have more items tell me and I will edit it -->

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="0dp"
    android:weightSum="1"
    android:orientation="horizontal" >

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.7"
        android:orientation="vertical" >
      <!-- replaced width with 0dp also here -->

        <TextView
            android:id="@+id/currencyNameTV"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="15dp"
            android:text="text"/>

        <TextView
            android:id="@+id/currencyCodeTV"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="15px"
            android:textSize="18dp"
            android:text="text"/>

    </LinearLayout>

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.3"
        android:orientation="vertical"
        android:layout_gravity="center_horizontal" >

        <TextView
            android:id="@+id/currencyRateTV"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="text"
            android:textSize="30dp"
            android:layout_marginLeft="15px"
            android:layout_marginTop="15px"
            android:gravity="center_horizontal" />

    </LinearLayout>

</LinearLayout>

关于android - 自定义 ListView 适配器 Android，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41145911/