android - 如何从 Firebase 中检索数据并在 CardView 中很好地显示
问题描述
我创建了 CreateEvent.java 模块来将数据上传到 firebase。但是如何检索数据并显示在 Cardlist 中？例如在下面的 xml 文件中显示。而且如果firebase中有超过1个数据，如何显示我在xml文件中创建的多个卡片列表？
创建事件.java
package com.example.edward.eventmanagementsystem.ManageEvent;
import android.Manifest;
import android.app.DatePickerDialog;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import com.example.edward.eventmanagementsystem.R;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.storage.FirebaseStorage;
import com.google.firebase.storage.OnProgressListener;
import com.google.firebase.storage.StorageReference;
import com.google.firebase.storage.UploadTask;
import java.util.Calendar;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Pattern;
import static android.widget.Toast.LENGTH_SHORT;
public class CreateEvent extends Activity {
private static final String TAG = "activity_create_event";
private Uri filePath;
private TextView mDisplayDate;
private DatePickerDialog.OnDateSetListener mDateSetListener;
private DatabaseReference mDatabaseReference;
private Button mRegisterButton;
EditText mEventNameText, mContactNumText, mEventLocationText;
TextView mEventDate;
RadioGroup mEventType;
FirebaseStorage storage;
StorageReference storageRef,imageRef;
ProgressDialog progressDialog;
UploadTask uploadTask;
Uri uriImage = Uri.parse("com.example.edward.eventmanagementsystem.ManageEvent/"+ R.drawable.ic_launcher_background);
public static final int PICK_IMAGE = 1;
ImageView mimageToUpload;
@Override
protected void onCreate(Bundle savedInstanceState) {
FirebaseDatabase firebaseDatabase;
mDatabaseReference = FirebaseDatabase.getInstance().getReference().child("ListEventInformation").push();
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_create_event);
mRegisterButton = (Button)findViewById(R.id.btnRegisterEvent);
storage = FirebaseStorage.getInstance();
storageRef = storage.getReference();
mDisplayDate = (TextView) findViewById(R.id.RegisterEventStartDate);
mDisplayDate.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Calendar cal = Calendar.getInstance();
int year = cal.get(Calendar.YEAR);
int month = cal.get(Calendar.MONTH);
int day = cal.get(Calendar.DAY_OF_MONTH);
DatePickerDialog dialog = new DatePickerDialog(
CreateEvent.this,
android.R.style.Theme_Holo_Light_Dialog_MinWidth,
mDateSetListener,
year, month, day);
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
dialog.show();
}
});
mDateSetListener = new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet(DatePicker view, int year, int month, int day) {
month = month + 1;
Log.d(TAG, "onDateSet: date: mm/dd/yyyy: " + month + "/" + day + "/" + year);
String date = month + "/" + day + "/" + year;
mDisplayDate.setText(date);
}
};
//perform action upload image
mimageToUpload = (ImageView) findViewById(R.id.imageToUpload);
//insert data to database
mEventNameText = (EditText) findViewById(R.id.RegisterEventName);
mContactNumText = (EditText) findViewById(R.id.RegisterContactNumber);
mEventDate = (TextView) findViewById(R.id.RegisterEventStartDate);
mEventType = (RadioGroup) findViewById(R.id.RegisterEventRadiogroup);
mEventLocationText = (EditText) findViewById(R.id.RegisterEventLocation);
mimageToUpload = (ImageView) findViewById(R.id.imageToUpload);
mRegisterButton = (Button) findViewById(R.id.btnRegisterEvent);
mimageToUpload.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (ContextCompat.checkSelfPermission(CreateEvent.this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED){
selectPdf();
}
else {
ActivityCompat.requestPermissions(CreateEvent.this,new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},9);
}
}
});
mRegisterButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int selectedId = mEventType.getCheckedRadioButtonId();
RadioButton radioButton = (RadioButton)findViewById(selectedId);
final String name = mEventNameText.getText().toString().trim();
final String contact = mContactNumText.getText().toString().trim();
final String date = mEventDate.getText().toString().trim();
final String type = radioButton.getText().toString().trim();
final String location = mEventLocationText.getText().toString().trim();
if (TextUtils.isEmpty(name)) {
mEventNameText.setError("Enter First Name!");
return;
}
if (TextUtils.isEmpty(date)) {
mEventDate.setError("Enter Date!");
return;
}
if (TextUtils.isEmpty(type)) {
radioButton.setError("Enter Phone Number!");
return;
}
if(isValidPhone(contact)){
Toast.makeText(getApplicationContext(),"Phone number is valid",Toast.LENGTH_SHORT).show();
}else {
mContactNumText.setError("Phone number is not valid");
Toast.makeText(getApplicationContext(),"Phone number is not valid",Toast.LENGTH_SHORT).show();
return;
}
if (TextUtils.isEmpty(location)) {
mEventLocationText.setError("Enter Location!");
return;
}
Map userInfo = new HashMap();
userInfo.put("mEventNameText", name);
userInfo.put("mContactNumText", contact);
userInfo.put("mEventDate", date);
userInfo.put("radioButton", type);
userInfo.put("mEventLocationText", location);
mDatabaseReference.updateChildren(userInfo);
final String fileName = System.currentTimeMillis()+"";
if(uriImage != null) {
StorageReference storageReference = storage.getReference();
storageReference.child("profileImageUrl").child(fileName).putFile(uriImage)
.addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
@Override
public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
String url = taskSnapshot.getMetadata().getReference().getDownloadUrl().toString();
mDatabaseReference.child("profileImageUrl").setValue(url).addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()){ }
else{
Toast.makeText(getApplicationContext(),"File not Successfully Uploaded",LENGTH_SHORT).show(); }
}
});
}
}).addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Toast.makeText(getApplicationContext(),"File not Successfully Uploaded",LENGTH_SHORT).show();
}
}).addOnProgressListener(new OnProgressListener<UploadTask.TaskSnapshot>() {
@Override
public void onProgress(UploadTask.TaskSnapshot taskSnapshot) {
}
});
}else{
}
Toast.makeText(getApplicationContext(),"New event created successfully!",LENGTH_SHORT).show();
Intent ManageEventMenu = new Intent(CreateEvent.this, com.example.edward.eventmanagementsystem.ManageEvent.ManageEventMenu.class);
startActivity(ManageEventMenu);
}
});
}
public boolean isValidPhone(CharSequence phone) {
boolean check=false;
if(!Pattern.matches("[a-zA-Z]+", phone))
{
if(phone.length() < 10 || phone.length() > 11)
{
check = false;
}
else
{
check = true;
}
}
else
{
check=false;
}
return check;
}
private void selectPdf() {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_OPEN_DOCUMENT);
startActivityForResult(intent,86);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 86 && resultCode == RESULT_OK && data != null){
final Uri imageUri = data.getData();
uriImage = imageUri;
mimageToUpload.setImageURI(uriImage);
}
else {
Toast.makeText(getApplicationContext(),"Please select file", LENGTH_SHORT).show();
}
}
}
我想以这种方式显示数据。我想在从 CreateEvent.java 上传时显示从 Firebase 创建的数据的 xml 文件示例
activity_list_of_event.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="@drawable/gradientwallpaper">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Events"
android:layout_marginLeft="10dp"
android:textStyle="bold"
android:layout_marginTop="20dp"
android:textSize="24dp"
android:textColor="@color/white"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Total Created Event"
android:layout_marginLeft="10dp"
android:textSize="16dp"
android:textColor="@color/white"
android:layout_marginTop="10dp"/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_marginTop="10dp"
android:layout_marginBottom="5dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Upcoming"
android:layout_marginLeft="10dp"
android:textSize="16dp"
android:textColor="@color/white"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Pass"
android:gravity="right"
android:layout_marginRight="10dp"
android:textSize="16dp"
android:textColor="@color/white"/>
</LinearLayout>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="10dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/white"
android:padding="10dp"
android:weightSum="10">
<LinearLayout
android:layout_width="100dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_weight="4"
android:orientation="vertical">
<TextView
android:id="@+id/item_month"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Month" />/ android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
<TextView
android:id="@+id/item_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Date" />/ android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
</LinearLayout>
<LinearLayout
android:layout_width="200dp"
android:layout_height="wrap_content"
android:layout_weight="4"
android:orientation="vertical">
<TextView
android:id="@+id/item_eventName"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Event Name"
android:textStyle="bold" />/android:textScaleX="18sp"
<TextView
android:id="@+id/item_contactNumber"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Contact Number"
android:textStyle="bold" />
<TextView
android:id="@+id/item_type"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Type of event"
android:textStyle="bold" />
<TextView
android:id="@+id/itemLocation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Location"
android:textStyle="bold" />
</LinearLayout>
<ImageView
android:id="@+id/item_image"
android:layout_width="75dp"
android:layout_height="75dp"
android:background="@color/white"
android:scaleType="centerCrop"
android:src="@drawable/pic1" />
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
解决方案
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