无法解析 Codepath `Todo App` 教程中的符号 `FileUtils`(Android) [英] Cannot resolve symbol `FileUtils` in Codepath `Todo App` tutorial (Android)
问题描述
我正在尝试遵循 Codepath (https://guides.txt) 中的 Todo
应用教程.codepath.com).
I'm trying to follow a Todo
app tutorial from Codepath (https://guides.codepath.com).
来源:https://guides.codepath.com/android/Basic-Todo-App-教程
据我所知,我已经按照教程进行操作,但遇到了以下问题.
As far as I can tell I've followed the tutorial, but am getting the below issue.
Cannot resolve symbol `FileUtils`
MainActivity.Java
package com.codepath.simpletodo;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
private ArrayList<String> items;
private ArrayAdapter<String> itemsAdapter;
private ListView lvItems;
private void readItems() {
File filesDir = getFilesDir();
File todoFile = new File(filesDir, "todo.txt");
try {
items = new ArrayList<String>(FileUtils.readLines(todoFile));
} catch (IOException e) {
items = new ArrayList<String>();
}
}
private void writeItems() {
File filesDir = getFilesDir();
File todoFile = new File(filesDir, "todo.txt");
try {
FileUtils.writeLines(todoFile, items);
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lvItems = (ListView) findViewById(R.id.lvItems);
items = new ArrayList<String>();
itemsAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, items);
lvItems.setAdapter(itemsAdapter);
items.add("Default item");
items.add("Another default item");
items.add("The third default item");
// setup remove listener method call
setupListViewListener();
}
// Attaches a long click listener to the listview
private void setupListViewListener() {
lvItems.setOnItemLongClickListener(
new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> adapter,
View item, int pos, long id) {
// Remove item within array at position
items.remove(pos);
// Refresh the adapter
itemsAdapter.notifyDataSetChanged();
// Return true consumes the long click event (marks it handled)
return true;
}
});
}
public void onAddItem(View v) {
EditText etNewItem = (EditText) findViewById(R.id.etNewItem);
String itemText = etNewItem.getText().toString();
itemsAdapter.add(itemText);
etNewItem.setText("");
}
}
activity_mail.xml
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/lvItems"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_above="@+id/btnAddItem" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/etNewItem"
android:layout_alignTop="@+id/btnAddItem"
android:hint="Enter a new item"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_toLeftOf="@+id/btnAddItem"
android:layout_toStartOf="@+id/btnAddItem"
android:layout_alignParentBottom="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add Item"
android:id="@+id/btnAddItem"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:onClick="onAddItem"
/>
我对 Android 非常陌生,并且很高兴能够开始工作,因为我还没有足够的背景知识,无法对调试抱有任何希望.
I'm extremely new to Android and would be so happy just to get things to work, as I don't have enough background yet to have any hope at debugging.
任何指导将不胜感激.
app/build.gradle
原始格式
android {
compileSdkVersion 24
buildToolsVersion "24.0.0"
defaultConfig {
applicationId "com.codepath.simpletodo"
minSdkVersion 14
targetSdkVersion 24
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:24.0.0'
}
我尝试了包括 'org.apache.commons:commons-io:1.3.2'
的各种组合.
I've tried various combinations of including 'org.apache.commons:commons-io:1.3.2'
.
- 将
'com.android.support:appcompat-v7:24.0.0'
替换为'org.apache.commons:commons-io:1.3.2'
- 将两者放在同一行:
compile 'com.android.support:appcompat-v7:24.0.0', 'org.apache.commons:commons-io:1.3.2'
. - 将两者放在不同的行:
compile 'com.android.support:appcompat-v7:24.0.0' compile 'org.apache.commons:commons-io:1.3.2'
.
- Replacing
'com.android.support:appcompat-v7:24.0.0'
with'org.apache.commons:commons-io:1.3.2'
- Putting both on same line:
compile 'com.android.support:appcompat-v7:24.0.0', 'org.apache.commons:commons-io:1.3.2'
. - Putting both on separate lines:
compile 'com.android.support:appcompat-v7:24.0.0' compile 'org.apache.commons:commons-io:1.3.2'
.
但是在尝试 Gradle 项目同步
时,出现以下消息失败.
But when attempting the Gradle project sync
, there is a failure with below message.
Error:(24, 13) Failed to resolve: compile org.apache.commons:commons-io:1.3.2
更新 2
最终的工作版本需要看起来像这样.
UPDATE 2
The final working version needed to look like this.
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:24.0.0'
compile group: 'org.apache.commons', name: 'commons-io', version: '1.3.2'
}
推荐答案
implementation 'org.apache.commons:commons-io:1.3.2'
包含 FileUtils 类.您应该将其添加到您的依赖项中.
implementation 'org.apache.commons:commons-io:1.3.2'
contains FileUtils class. You should add this to your dependencies.
这篇关于无法解析 Codepath `Todo App` 教程中的符号 `FileUtils`(Android)的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!