Java文件

Question

嘿伙计们！

公平警告：我对编程总体上非常新，更不用说java和android了，所以说实话，我可能甚至不知道如何以正确的方式提出正确的问题。因此，我感谢任何愿意花时间看过去的人，如果可以的话，给予帮助！此外，如果你能找到一种方法来愚弄你所拥有的任何解决方案，并像我三岁那样解释它，我也非常感激。我已经查看了developer.android.com，所有技术术语都让我的困惑变得更糟。

所以我到目前为止所做的是

我有一个以下代码（包括java和xml），一旦打开它就会显示三个类别＆＃39;我的应用程序（即activities.java文件）在activity_main.xml文件中。由于现在这三个都是相同的，我已经在下面发布了MidlandsActivity.java的代码。

OnClick会打开您点击的任何活动类别，并在list_items.xml文件中显示arraylist （如MidlandsActivity.java文件中所示）。

所以现在......我希望能做的是：

我希望您能够点击列表中的任何项目（您目前可以使用但目前无法执行任何操作）然后显示您在新活动中点击的任何列表项目（我猜对了吗？ ListDetails.java是为了进行对话，但我还没有制作，因为我迷失了。或者它应该被编码到MidlandsActivity.java和每个额外的类别活动中，例如？）。然后将该活动显示到list_details.xml文件，以便完全查看所选类别arraylist中的数据。

目前我确实为此设置了xml文件（list_details.xml），但我不知道接下来需要做什么或者放在哪里。

任何帮助或建议？

Java文件

MidlandsActivity.java

package com.example.android.hauntedsc;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;

import java.util.ArrayList;

public class MidlandsActivity extends AppCompatActivity {

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

    //Create an array of words
    final ArrayList<Word> words = new ArrayList<Word>();
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));
    words.add(new Word(
            "title",
            "address\n" +
            "citystatezip\n\n",
            "The Facts:\n\n" +
            "factstext\n\n" +
            "The Legend:\n\n" +
            "legendtext",
            R.drawable.haunted));


    // Create an {@link ArrayAdapter}, whose data source is a list of Strings. The
    // adapter knows how to create layouts for each item in the list, using the
    // simple_list_item_1.xml layout resource defined in the Android framework.
    // This list item layout contains a single {@link TextView}, which the adapter will set to
    // display a single word.
    WordAdapter adapter =
            new WordAdapter(this, words, R.color.category_midlands);

    // Find the {@link ListView} object in the view hierarchy of the {@link Activity}.
    // There should be a {@link ListView} with the view ID called list, which is declared in the
    // word_list.xml file.
    ListView listView = (ListView) findViewById(R.id.list);

    // Make the {@link ListView} use the {@link ArrayAdapter} we created above, so that the
    // {@link ListView} will display list items for each word in the list of words.
    // Do this by calling the setAdapter method on the {@link ListView} object and pass in
    // 1 argument, which is the {@link ArrayAdapter} with the variable name itemsAdapter.
    listView.setAdapter(adapter);

    // Set a click listener to play the audio when the list item is clicked on
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
            // Get the {@link Word} object at the given position the user clicked on
            Word word = words.get(position);
        }
    });
  }
}

MainActivity.java

package com.example.android.hauntedsc;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Set the content of the activity to use the activity_main.xml layout file
    setContentView(R.layout.activity_main);

    //Find the View that shows the lowcountry catagory
    TextView lowcountry = (TextView)findViewById(R.id.lowcountry);
    //set a clicklistener on that View
    lowcountry.setOnClickListener(new View.OnClickListener() {
        // The code in this method will be executed when the numbers category is clicked on.
        @Override
        public void onClick(View view) {
            //Create a new intent to open the (@Link LowcountryActivity)
            Intent lowcountryIntent = new Intent(MainActivity.this,LowcountryActivity.class);
            //Start New Activity
            startActivity(lowcountryIntent);
        }
    });

    //Find the View that shows the upstate catagory
    TextView upstate = (TextView)findViewById(R.id.upstate);
    //set a clicklistener on that View
    upstate.setOnClickListener(new View.OnClickListener() {
        // The code in this method will be executed when the numbers category is clicked on.
        @Override
        public void onClick(View view) {
            //Create a new intent to open the (@Link UpstateActivity)
            Intent upstateIntent = new Intent(MainActivity.this,UpstateActivity.class);
            //Start New Activity
            startActivity(upstateIntent);
        }
    });

    //Find the View that shows the midlands catagory
    TextView midlands = (TextView)findViewById(R.id.midlands);
    //set a clicklistener on that View
    midlands.setOnClickListener(new View.OnClickListener() {
        // The code in this method will be executed when the numbers category is clicked on.
        @Override
        public void onClick(View view) {
            //Create a new intent to open the (@Link midlandsActivity)
            Intent midlandsIntent = new Intent(MainActivity.this,MidlandsActivity.class);
            //Start New Activity
            startActivity(midlandsIntent);
        }
    });

  }
}

Word.java

package com.example.android.hauntedsc;

public class Word {

//
private String mDescription;

//
private String mAddress;

//
private String mTitle;

/** Image resource ID for the word */
private int mImageResourceId = NO_IMAGE_PROVIDED;

/** Constant value that represents no image was provided for this word */
private static final int NO_IMAGE_PROVIDED = -1;

public Word(String description, String address, String title) {
    mDescription = description;
    mAddress = address;
    mTitle = title;
}

public Word(String description, String address, String title,  int imageResourceId) {
    mDescription = description;
    mAddress = address;
    mTitle = title;
    mImageResourceId = imageResourceId;
}

//Get the description of the list item.
public String getdescription() { return mDescription;}
//Get the address of the list item.
public String getaddress() { return mAddress; }
//Get the title of the list item.
public String gettitle() { return mTitle; }
//Return the image resource ID of the list item.
public int getImageResourceId() { return mImageResourceId; }
//Returns whether or not there is an image for this list item.
public boolean hasImage() { return mImageResourceId != NO_IMAGE_PROVIDED; }
}

WordAdapter.java

package com.example.android.hauntedsc;

import android.content.Context;
import android.support.v4.content.ContextCompat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.ArrayList;

public class WordAdapter extends ArrayAdapter<Word> {

//Resource ID for background color of this list of words
private int mColorResourceId;

// Here, we initialize the ArrayAdapter's internal storage for the context and the list.
// the second argument is used when the ArrayAdapter is populating a single TextView.
// Because this is a custom adapter for two TextViews and an ImageView, the adapter is not
// going to use this second argument, so it can be any value. Here, we used 0.
public WordAdapter(Context context, ArrayList<Word> words, int colorResourceId) {
    super(context, 0, words);
    mColorResourceId = colorResourceId;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // Check if the existing view is being reused, otherwise inflate the view
    View listItemView = convertView;
    if(listItemView == null) {
        listItemView = LayoutInflater.from(getContext()).inflate(
                R.layout.list_item, parent, false);
    }

    // Get the {@link AndroidFlavor} object located at this position in the list
    Word currentWord = getItem(position);

    // Find the TextView in the list_item.xml layout with the ID version_name
    TextView titleTextView = (TextView) listItemView.findViewById(R.id.description_text_view);
    // Get the version name from the current AndroidFlavor object and
    // set this text on the name TextView
    titleTextView.setText(currentWord.gettitle());

    // Find the TextView in the list_item.xml layout with the ID version_number
    TextView addressTextView = (TextView) listItemView.findViewById(R.id.address_text_view);
    // Get the version number from the current AndroidFlavor object and
    // set this text on the number TextView
    addressTextView.setText(currentWord.getaddress());

    // Find the TextView in the list_item.xml layout with the ID version_number
    TextView descriptionTextView = (TextView) listItemView.findViewById(R.id.title_text_view);
    // Get the version number from the current AndroidFlavor object and
    // set this text on the number TextView
    descriptionTextView.setText(currentWord.getdescription());

    // Find the ImageView in the list_item.xml layout with the ID image.
    ImageView imageView = (ImageView) listItemView.findViewById(R.id.image_view);
    // Check if an image is provided for this word or not
    if (currentWord.hasImage()) {
        // If an image is available, display the provided image based on the resource ID
        imageView.setImageResource(currentWord.getImageResourceId());
        // Make sure the view is visible
        imageView.setVisibility(View.VISIBLE);
    } else {
        // Otherwise hide the ImageView (set visibility to GONE)
        imageView.setVisibility(View.GONE);
    }

    //Set the theme color for the list item
    View textContainer = listItemView.findViewById(R.id.text_container);
    //find the color that the resource ID maps too
    int color = ContextCompat.getColor(getContext(), mColorResourceId);
    //Set the background color of the text container View
    textContainer.setBackgroundColor(color);

    //Set the theme color for the list item
    View imageContainer = listItemView.findViewById(R.id.list_item_layout);
    //find the color that the resource ID maps too
    int icolor = ContextCompat.getColor(getContext(), mColorResourceId);
    //Set the background color of the text container View
    imageContainer.setBackgroundColor(icolor);


    // Return the whole list item layout (containing 2 TextViews and an ImageView)
    // so that it can be shown in the ListView
    return listItemView;
}
}

XML文件

activity_main.xml中

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:background="@color/background"
android:orientation="vertical"
tools:context="com.example.android.hauntedsc.MainActivity">

<!-- Lowcountry category ((formerly numbers))-->
<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/category_lowcountry">
    <TextView
        android:id="@+id/lowcountry"
        style="@style/CategoryStyle"
        android:background="?android:attr/selectableItemBackground"
        android:text="@string/category_lowcountry" />
</FrameLayout>

<!-- Midlands category ((formerly family))-->
<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/category_midlands">
    <TextView
        android:id="@+id/midlands"
        style="@style/CategoryStyle"
        android:background="?android:attr/selectableItemBackground"
        android:text="@string/category_midlands" />
</FrameLayout>

<!-- Upstate category ((formerly colors))-->
<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/category_upstate">
    <TextView
        android:id="@+id/upstate"
        style="@style/CategoryStyle"
        android:background="?android:attr/selectableItemBackground"
        android:text="@string/category_upstate" />
</FrameLayout>
</LinearLayout>

list_items.xml

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/list_item_layout"
android:layout_width="match_parent"
android:layout_height="@dimen/list_item_height"
android:background="@color/background"
android:orientation="horizontal">

<ImageView
    android:id="@+id/image_view"
    android:layout_width="@dimen/list_item_height"
    android:layout_height="@dimen/list_item_height"/>

<LinearLayout
    android:id="@+id/text_container"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true"
    android:layout_toRightOf="@id/image_view"
    android:orientation="vertical"
    android:paddingLeft="16dp">

    <TextView
        android:id="@+id/title_text_view"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:gravity="center_vertical"
        android:layout_weight="1"
        android:textAppearance="?android:textAppearanceMedium"
        android:textColor="@android:color/white"
        android:textStyle="bold"
        android:paddingTop="4dp"
        android:paddingRight="8dp"
        android:paddingBottom="4dp"
        tools:text=""/>

    <TextView
        android:id="@+id/address_text_view"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="2"
        android:gravity="center_vertical"
        android:textAppearance="?android:textAppearanceMedium"
        android:textColor="@android:color/white"
        android:paddingTop="4dp"
        android:paddingRight="8dp"
        android:paddingBottom="4dp"
        tools:text="" />

    <TextView
        android:id="@+id/description_text_view"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="0"
        android:gravity="top"
        android:textAppearance="?android:textAppearanceMedium"
        android:textColor="@android:color/white"
        android:paddingTop="4dp"
        android:paddingRight="8dp"
        android:paddingBottom="4dp"
        tools:text="" />
</LinearLayout>
</RelativeLayout>

list_details.xml

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

    <TextView
        android:id="@+id/detail_title_text_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:textAppearanceMedium"
        android:textColor="@android:color/white"
        android:textStyle="bold"
        android:paddingTop="4dp"
        android:paddingRight="8dp"
        android:paddingBottom="4dp"/>

    <TextView
        android:id="@+id/detail_address_text_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:textAppearanceMedium"
        android:textColor="@android:color/white"
        android:paddingTop="4dp"
        android:paddingRight="8dp"
        android:paddingBottom="4dp"/>

    <TextView
        android:id="@+id/detail_description_text_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:textAppearanceMedium"
        android:textColor="@android:color/white"
        android:paddingTop="4dp"
        android:paddingRight="8dp"
        android:paddingBottom="4dp"/>

    </LinearLayout>

</RelativeLayout>

</ScrollView>

Answer 1

创建一个新活动并将其命名为ListDetails.java，然后将以下内容添加到现有的Midlands.java

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

     @Override public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) { 

    // Get the {@link Word} object at the given position the user clicked on 

    //Word word = words.get(position);

Intent intent = new Intent(Midlands.this, ListDetails.class);
startActivity(intent);

 }

Answer 2

所以，您只是希望自己的ListView项目带您进入新的Activity？

在您设置MidlandsActivity ListView的{{1}}中执行此操作：

onClick

这样做是启动一个新的listView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) { Word word = words.get(position); Intent intent = new Intent(MidlandsActivity.this, ListDetails.class); intent.putExtra("myWord", word); startActivity(intent); } });并传递Activity对象的值。但是，您的Word类将实现Word接口，以便通过意图传递。你可以找到一个很好的答案here。

准备就绪之后，您的对象将被传递到您的Parcelable活动，您可以使用

在ListDetails中检索它

onCreate(..)

Answer 3

除了@Suhayl SH编写的内容之外 - 您已经说过，您希望所点击的项目在您开始的活动中可见。在给定的代码中，此活动将是ListDetails。为此，请使用Suhayl提供的代码并添加以下内容：

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

     @Override public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) { 

    // Get the {@link Word} object at the given position the user clicked on 

    //Word word = words.get(position);

   Intent intent = new Intent(Midlands.this, ListDetails.class);
   Word word = word.get(position);
   intent.putExtra("wordToBeDisplayed",word);
   startActivity(intent);

 }

然后在ListDetails活动中，您可以使用以下方式显示单词：

Bundle b = getIntent().getExtras();
Word word = (Word) b.get("wordToBeDisplayed");
// The rest depends on your preferences about what to display

Android，Java，Onclick，＆amp;需要Arraylist帮助（我想？）

Java文件

MidlandsActivity.java

MainActivity.java

Word.java

WordAdapter.java

XML文件

activity_main.xml中

list_items.xml

list_details.xml

3 个答案: