Java 列表视图不填充
我正试图按照Udacity的教程,在listview示例中显示虚拟列表 MainActivity.java:Java 列表视图不填充,java,android,Java,Android,我正试图按照Udacity的教程,在listview示例中显示虚拟列表 MainActivity.java: package com.example.android.sunshine.app; import android.app.Fragment; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.LayoutInflater; import andro
package com.example.android.sunshine.app;
import android.app.Fragment;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Create some dummy data for the ListView. Here's a sample weekly forecast
String[] data = {
"Mon 6/23 - Sunny - 31/17",
"Tue 6/24 - Foggy - 21/8",
"Wed 6/25 - Cloudy - 22/17",
"Thurs 6/26 - Rainy - 18/11",
"Fri 6/27 - Foggy - 21/10",
"Sat 6/28 - TRAPPED IN WEATHERSTATION - 23/18",
"Sun 6/29 - Sunny - 20/7"
};
List<String> weekForecast = new ArrayList<String>(Arrays.asList(data));
// Now that we have some dummy forecast data, create an ArrayAdapter.
// The ArrayAdapter will take data from a source (like our dummy forecast) and
// use it to populate the ListView it's attached to.
ArrayAdapter<String> forecastAdapter =
new ArrayAdapter<String>(
getActivity(), // The current context (this activity)
R.layout.list_item_forecast, // The name of the layout ID.
R.id.list_item_forecast_textview, // The ID of the textview to populate.
weekForecast);
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
}
package com.example.android.sunshine.app;
导入android.app.Fragment;
导入android.os.Bundle;
导入android.support.v7.app.AppActivity;
导入android.view.LayoutInflater;
导入android.view.Menu;
导入android.view.MenuItem;
导入android.view.view;
导入android.view.ViewGroup;
导入android.widget.ArrayAdapter;
导入java.util.ArrayList;
导入java.util.array;
导入java.util.List;
公共类MainActivity扩展了AppCompatActivity{
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@凌驾
公共布尔onCreateOptions菜单(菜单){
//为菜单充气;这会将项目添加到操作栏(如果存在)。
getMenuInflater().充气(右菜单菜单菜单主菜单);
返回true;
}
@凌驾
公共布尔值onOptionsItemSelected(菜单项项){
//处理操作栏项目单击此处。操作栏将
//自动处理Home/Up按钮上的点击,只要
//在AndroidManifest.xml中指定父活动时。
int id=item.getItemId();
//noinspection SimplifiableIf语句
if(id==R.id.action\u设置){
返回true;
}
返回super.onOptionsItemSelected(项目);
}
公共静态类占位符片段扩展了片段{
公共占位符片段(){
}
@凌驾
创建视图上的公共视图(布局、充气机、视图组容器、,
Bundle savedInstanceState){
//为ListView创建一些虚拟数据
字符串[]数据={
“周一6/23 - 阳光明媚-2017年11月31日“,
“6月24日星期二-大雾-21月8日”,
“6月25日星期三-多云-17月22日”,
“6月26日星期四-雨季-11月18日”,
“6月27日星期五-大雾-10月21日”,
“Sat 6/28-被困在气象站-23/18”,
“太阳6/29-晴朗-20/7”
};
List-weekForecast=newarraylist(Arrays.asList(data));
//现在我们有了一些虚拟预测数据,创建一个ArrayAdapter。
//ArrayAdapter将从源(如我们的虚拟预测)获取数据,然后
//使用它填充它附加到的ListView。
阵列适配器前向适配器=
新阵列适配器(
getActivity(),//当前上下文(此活动)
R.layout.list\u item\u forecast,//布局ID的名称。
R.id.list\u item\u forecast\u textview,//要填充的textview的id。
周预测);
视图根视图=充气机。充气(R.layout.fragment_main,容器,错误);
返回rootView;
}
}
}
Fragment_main.xml:
<FrameLayout 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=".MainActivityFragment">
<ListView
android:id="@+id/listview_forecast"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</FrameLayout>
list_item_forecast.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/list_item_forecast_textview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:minHeight="?android:attr/listPreferredItemHeight" />
这几天我一直在努力回顾教程。
请告诉我哪里出错了
谢谢。我在您的代码中没有看到调用
ArrayAdapter<String> forecastAdapter =
new ArrayAdapter<String>(
getActivity(), // The current context (this activity)
R.layout.list_item_forecast, // The name of the layout ID.
R.id.list_item_forecast_textview, // The ID of the textview to populate.
weekForecast);
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
((ListView) rootView.findViewById(R.id.listview_forecast)).setAdapter(forecastAdapter);
ArrayAdapter ForecasAdapter=
新阵列适配器(
getActivity(),//当前上下文(此活动)
R.layout.list\u item\u forecast,//布局ID的名称。
R.id.list\u item\u forecast\u textview,//要填充的textview的id。
周预测);
视图根视图=充气机。充气(R.layout.fragment_main,容器,错误);
((ListView)rootView.findViewById(R.id.ListView_forecast)).setAdapter(ForecasAdapter);
我在您的代码中没有看到调用
ArrayAdapter<String> forecastAdapter =
new ArrayAdapter<String>(
getActivity(), // The current context (this activity)
R.layout.list_item_forecast, // The name of the layout ID.
R.id.list_item_forecast_textview, // The ID of the textview to populate.
weekForecast);
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
((ListView) rootView.findViewById(R.id.listview_forecast)).setAdapter(forecastAdapter);
ArrayAdapter ForecasAdapter=
新阵列适配器(
getActivity(),//当前上下文(此活动)
R.layout.list\u item\u forecast,//布局ID的名称。
R.id.list\u item\u forecast\u textview,//要填充的textview的id。
周预测);
视图根视图=充气机。充气(R.layout.fragment_main,容器,错误);
((ListView)rootView.findViewById(R.id.ListView_forecast)).setAdapter(ForecasAdapter);
我在您的代码中没有看到调用
ArrayAdapter<String> forecastAdapter =
new ArrayAdapter<String>(
getActivity(), // The current context (this activity)
R.layout.list_item_forecast, // The name of the layout ID.
R.id.list_item_forecast_textview, // The ID of the textview to populate.
weekForecast);
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
((ListView) rootView.findViewById(R.id.listview_forecast)).setAdapter(forecastAdapter);
ArrayAdapter ForecasAdapter=
新阵列适配器(
getActivity(),//当前上下文(此活动)
R.layout.list\u item\u forecast,//布局ID的名称。
R.id.list\u item\u forecast\u textview,//要填充的textview的id。
周预测);
视图根视图=充气机。充气(R.layout.fragment_main,容器,错误);
((ListView)rootView.findViewById(R.id.ListView_forecast)).setAdapter(ForecasAdapter);
我在您的代码中没有看到调用
ArrayAdapter<String> forecastAdapter =
new ArrayAdapter<String>(
getActivity(), // The current context (this activity)
R.layout.list_item_forecast, // The name of the layout ID.
R.id.list_item_forecast_textview, // The ID of the textview to populate.
weekForecast);
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
((ListView) rootView.findViewById(R.id.listview_forecast)).setAdapter(forecastAdapter);
ArrayAdapter ForecasAdapter=
新阵列适配器(
getActivity(),//当前上下文(此活动)
R.layout.list\u item\u forecast,//布局ID的名称。
R.id.list\u item\u forecast\u textview,//要填充的textview的id。
周预测);
视图根视图=充气机。充气(R.layout.fragment_main,容器,错误);
((ListView)rootView.findViewById(R.id.ListView_forecast)).setAdapter(ForecasAdapter);
在return语句之前添加这两行代码
ListView forecastlist=(ListView)findViewById(R.id.listview_forecast);
forecastlist.setAdapter(forecastAdapter);
在return语句之前添加这两行代码
ListView forecastlist=(ListView)findViewById(R.id.listview_forecast);
forecastlist.setAdapter(forecastAdapter);
在返回之前添加这两行代码