1
私はAndroidアプリケーションの開発を始めました。私はXAMPPを使ってデータベース（MYSQL）とphpを生成し、抽出したデータをJSONに変換しました。ただし、Android Recyclerviewに次のJSON出力を表示できず、このアプリケーションの作成中にエラーが発生していません。私はこのウェブサイトからいくつかの他の例/ソリューションを紹介しましたが、私はまだこの問題を解決できませんでした。私が使用したコードは以下の通りです。どの部分が訂正されたり欠落したりするのか分かりますか？ herblist.phpMySQLデータがAndroid RecyclerViewに表示されていません（Logcatエラー：memtrackモジュールを読み込めませんでした）
[{"h_name":"Basil","h_image":"http:\/\/localhost\/Herb\/Herb_image\/basil.jpg"},{"h_name":"Cilantro","h_image":"http:\/\/localhost\/Herb\/Herb_image\/cilantro.jpg"},{"h_name":"Kaffir lime leaf","h_image":"http:\/\/localhost\/Herb\/Herb_image\/kaffir_lime.jpg"},{"h_name":"Lemongrass","h_image":"http:\/\/localhost\/Herb\/Herb_image\/lemongrass.jpg"},{"h_name":"Mint","h_image":"http:\/\/localhost\/Herb\/Herb_image\/mint.jpg"},{"h_name":"Oregano","h_image":"http:\/\/localhost\/Herb\/Herb_image\/oregano.jpg"},{"h_name":"Pandan leaf","h_image":"http:\/\/localhost\/Herb\/Herb_image\/pandan.jpg"},{"h_name":"Parsley","h_image":"http:\/\/localhost\/Herb\/Herb_image\/parsley.jpg"},{"h_name":"Rosemary","h_image":"http:\/\/localhost\/Herb\/Herb_image\/rosemary.jpg"},{"h_name":"Thyme","h_image":"http:\/\/localhost\/Herb\/Herb_image\/thyme.jpg"}]
searchActivity.java（主活性）
によって生成（JSONにMYSQLデータを変換する）herblist.php
<?php
include 'dbConnect.php';
// Create connection
$conn = new mysqli($HostName, $HostUser, $HostPass, $DatabaseName);
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
mysqli_set_charset($conn, 'utf8');
$sql = "SELECT * FROM herb";
$result = $conn->query($sql);
if ($result->num_rows >0) {
while($row[] = $result->fetch_assoc()) {
$tem = $row;
$json = json_encode($tem);
}
} else {
echo "No Results Found.";
}
echo $json;
$conn->close();
?>
JSON
public class searchActivity extends AppCompatActivity { List<DataAdapter> ListDataAdapter; RecyclerView recyclerView; String HTTP_JSON_URL = "http://localhost/Herb/herblist.php"; String Image_Name_JSON = "h_name"; String Image_URL_JSON = "h_image"; JsonArrayRequest RequestOfJSonArray ; RequestQueue requestQueue ; View view ; int RecyclerViewItemPosition ; RecyclerView.LayoutManager RecyclerViewLayoutManager; RecyclerView.Adapter recyclerViewadapter; ArrayList<String> ImageTitleNameArrayListForClick; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_search); ImageTitleNameArrayListForClick = new ArrayList<>(); ListDataAdapter = new ArrayList<>(); recyclerView = (RecyclerView) findViewById(R.id.recyclerview1); recyclerView.setHasFixedSize(true); RecyclerViewLayoutManager = new LinearLayoutManager(this); recyclerView.setAdapter(recyclerViewadapter); recyclerView.setLayoutManager(RecyclerViewLayoutManager); JSON_HTTP_CALL(); // Implementing Click Listener on RecyclerView. recyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() { GestureDetector gestureDetector = new GestureDetector(searchActivity.this, new GestureDetector.SimpleOnGestureListener() { @Override public boolean onSingleTapUp(MotionEvent motionEvent) { return true; } }); @Override public boolean onInterceptTouchEvent(RecyclerView Recyclerview, MotionEvent motionEvent) { view = Recyclerview.findChildViewUnder(motionEvent.getX(), motionEvent.getY()); if(view != null && gestureDetector.onTouchEvent(motionEvent)) { //Getting RecyclerView Clicked Item value. RecyclerViewItemPosition = Recyclerview.getChildAdapterPosition(view); // Showing RecyclerView Clicked Item value using Toast. Toast.makeText(searchActivity.this, ImageTitleNameArrayListForClick.get(RecyclerViewItemPosition), Toast.LENGTH_LONG).show(); } return false; } @Override public void onTouchEvent(RecyclerView Recyclerview, MotionEvent motionEvent) { } @Override public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { } }); } public void JSON_HTTP_CALL(){ RequestOfJSonArray = new JsonArrayRequest(HTTP_JSON_URL, new Response.Listener<JSONArray>() { @Override public void onResponse(JSONArray response) { ParseJSonResponse(response); } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { } }); requestQueue = Volley.newRequestQueue(searchActivity.this); requestQueue.add(RequestOfJSonArray); } public void ParseJSonResponse(JSONArray array){ for(int i = 0; i<array.length(); i++) { DataAdapter GetDataAdapter2 = new DataAdapter(); JSONObject json = null; try { json = array.getJSONObject(i); GetDataAdapter2.setImageTitle(json.getString(Image_Name_JSON)); // Adding image title name in array to display on RecyclerView click event. ImageTitleNameArrayListForClick.add(json.getString(Image_Name_JSON)); GetDataAdapter2.setImageUrl(json.getString(Image_URL_JSON)); } catch (JSONException e) { e.printStackTrace(); } ListDataAdapter.add(GetDataAdapter2); } recyclerViewadapter = new RecyclerViewAdapter(ListDataAdapter, this); recyclerView.setAdapter(recyclerViewadapter); } } DataAdapter.java（cardviewにおけるテキストのアダプタ部）
public class DataAdapter{
public String ImageURL;
public String ImageTitle;
public String getImageUrl() {return ImageURL;}
public void setImageUrl(String ImageServerUrl) {this.ImageURL = ImageServerUrl;}
public String getImageTitle() {return ImageTitle;}
public void setImageTitle(String ImageTitleName) {this.ImageTitle = ImageTitleName;}
}
ImageAdapter.java（cardviewにおける画像のアダプタ部）
public class ImageAdapter {
public static ImageAdapter imageAdapter;
public Network networkOBJ ;
public RequestQueue requestQueue1;
public ImageLoader Imageloader1;
public Cache cache1 ;
public static Context context1;
LruCache<String, Bitmap> LRUCACHE = new LruCache<String, Bitmap>(30);
private ImageAdapter(Context context) {
this.context1 = context;
this.requestQueue1 = RequestQueueFunction();
Imageloader1 = new ImageLoader(requestQueue1, new ImageLoader.ImageCache() {
@Override
public Bitmap getBitmap(String URL) {
return LRUCACHE.get(URL);
}
@Override
public void putBitmap(String url, Bitmap bitmap) {
LRUCACHE.put(url, bitmap);
}
});
}
public ImageLoader getImageLoader() {
return Imageloader1;
}
public static ImageAdapter getInstance(Context SynchronizedContext) {
if (imageAdapter == null) {
imageAdapter = new ImageAdapter(SynchronizedContext);
}
return imageAdapter;
}
public RequestQueue RequestQueueFunction() {
if (requestQueue1 == null) {
cache1 = new DiskBasedCache(context1.getCacheDir());
networkOBJ = new BasicNetwork(new HurlStack());
requestQueue1 = new RequestQueue(cache1, networkOBJ);
requestQueue1.start();
}
return requestQueue1;
}
}
RecyclerViewAdapter.java
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder> {
Context context;
List<DataAdapter> dataAdapters;
ImageLoader imageLoader;
public RecyclerViewAdapter(List<DataAdapter> getDataAdapter, Context context){
super();
this.dataAdapters = getDataAdapter;
this.context = context;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview, parent, false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}
@Override
public void onBindViewHolder(ViewHolder Viewholder, int position) {
DataAdapter dataAdapterOBJ = dataAdapters.get(position);
imageLoader = ImageAdapter.getInstance(context).getImageLoader();
imageLoader.get(dataAdapterOBJ.getImageUrl(),
ImageLoader.getImageListener(
Viewholder.VollyImageView,//Server Image
R.mipmap.ic_launcher,//Before loading server image the default showing image.
android.R.drawable.ic_dialog_alert //Error image if requested image dose not found on server.
)
);
Viewholder.VollyImageView.setImageUrl(dataAdapterOBJ.getImageUrl(), imageLoader);
Viewholder.ImageTitleTextView.setText(dataAdapterOBJ.getImageTitle());
}
@Override
public int getItemCount() {
return dataAdapters.size();
}
class ViewHolder extends RecyclerView.ViewHolder{
public TextView ImageTitleTextView;
public NetworkImageView VollyImageView ;
public ViewHolder(View itemView) {
super(itemView);
ImageTitleTextView = (TextView) itemView.findViewById(R.id.ImageNameTextView) ;
VollyImageView = (NetworkImageView) itemView.findViewById(R.id.VolleyImageView) ;
}
}
}
activity_search.xml（主活動のXMLファイル）
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerview1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</RelativeLayout>
cardview.xml
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/cardview1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
card_view:cardElevation="5dp"
card_view:contentPadding="5dp"
card_view:cardCornerRadius="5dp"
card_view:cardMaxElevation="5dp"
>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#ECEFF1">
<com.android.volley.toolbox.NetworkImageView
android:id="@+id/VolleyImageView"
android:layout_width="150dp"
android:layout_height="100dp"
android:src="@mipmap/ic_launcher"
android:layout_marginTop="10dp"
android:layout_marginBottom="10dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toEndOf="@+id/VolleyImageView"
android:textSize="20sp"
android:textColor="#000"
android:text="JSon Image Name"
android:id="@+id/ImageNameTextView"
android:layout_centerVertical="true"/>
</RelativeLayout>
</android.support.v7.widget.CardView>
感謝を置きます。しかし、問題は依然として続き、私はまだrecyclerviewが表示されていない理由を知りません。私もlistviewでこれをやろうとしましたが、同じ問題が発生します – DreamCrusher
あなたは何かエラーが発生しましたか？ – Munir
あなたはlogcatというエラーを意味しますか？ – DreamCrusher