我需要遍历Firebase架构，以获取每个workouts＆amp;的数据。在RecyclerView中显示它。
现在，我无法使用监听器和＆amp ;;遍历Firebase中的Schema。通过名为Program的POJO类获取它。
来自Firebase的JSON
{
"subscriptions" : {
"han@gmail,com" : {
"-KDnhRwHjssOejrqyenP" : {
"category" : "Strength",
"goal" : "This workout can be done while on the phone!",
"length" : 1,
"title" : "Hello Workouts",
"weeks" : {
"week1" : [ "High Knees", "Jumping Jacks", "Wall sit", "Pushups", "Sit-ups", "Step ups", "Squats", "Tricep dips on chair", "Plank", "High Knees running in place", "Lunges", "Pushup and rotation", "Side plank (alternate per round)", "Alternating Push-Up Plank", "Chest Expander", "Diamond Push-ups", "Dive Bomber Push-ups", "Butt Kickers", "Lying Triceps Lifts", "One Arm Side Push-up", "Overhead Arm Clap", "Overhead Press", "Power Circles", "Push-up and Rotation", "T Push-ups", "Reverse Plank", "Spiderman Push-up", "T Raise", "Tricep Dips", "Wall Push-ups", "Wide Arm Push-ups", "Burpees" ]
}
},
"-KDni3TN4NMyGXePyp92" : {
"category" : "Strength",
"goal" : "This workout can be done by a BABUJI",
"length" : 1,
"title" : "Indian Workouts",
"weeks" : {
"week1" : [ "Diamond Pushups", "Jackknives", "Plyo Lunges", "Plyo Squats", "Single leg plank (alternate per round)", "Plyo Lunges", "Pushup and rotation", "Weighted side plank (alternate per round)", "Alternating Push-Up Plank", "Chest Expander", "Diamond Push-ups", "Dive Bomber Push-ups", "One Arm Side Push-up", "Overhead Press", "Push-up and Rotation", "T Push-ups", "Spiderman Push-up", "Wide Arm Push-ups", "Burpee Pushups" ]
}
}
},
"obama@gmsil,com" : {
"-KDnfjROKeFAL9wccsxY" : {
"category" : "Mobility",
"goal" : "afternoon body weight workout",
"length" : 1,
"title" : "Afternoon HiiT",
"weeks" : {
"week1" : [ "High Knees", "Squats", "Lunges", "Diamond Push-ups", "Lying Triceps Lifts" ]
}
},
"-KDps90Dn6XtJc6Co00b" : {
"category" : "Strength",
"goal" : "goal",
"length" : 1,
"title" : "title",
"weeks" : {
"week1" : [ "Diamond Pushups", "Jackknives", "Plyo Lunges", "Plyo Squats", "Single leg plank (alternate per round)", "Plyo Lunges", "Pushup and rotation", "Weighted side plank (alternate per round)", "Alternating Push-Up Plank", "Chest Expander", "Diamond Push-ups", "Dive Bomber Push-ups", "One Arm Side Push-up", "Overhead Press", "Push-up and Rotation", "T Push-ups", "Spiderman Push-up", "Wide Arm Push-ups", "Burpee Pushups" ]
}
}
}
}
}
听众代码
public void FB(){
ref.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot snapshot) {
for (DataSnapshot postSnapshot: snapshot.getChildren()) {
System.out.println(postSnapshot.getValue());
//Program post = proSnapshot.getValue(Program.class);
}
}
@Override
public void onCancelled(FirebaseError firebaseError) {
System.out.println("The read failed: " + firebaseError.getMessage());
}
});
}
logcat的
03-28 08:52:53.966 23584-23584 / com.android.sam I / System.out:[-KDni3TN4NMyGXePyp92 = {weeks = {week1 = [Diamond Pushups，Jackknives，Plyo Lunges，Plyo Squats，Single leg木板（每轮交替），Plyo Lunges，俯卧撑和旋转，加权侧板（每轮交替），交替俯卧撑，胸部扩张器，钻石俯卧撑，潜水轰炸机俯卧撑，单臂侧俯卧撑，架空按压，俯卧撑和旋转，T型俯卧撑，蜘蛛侠俯卧撑，宽臂俯卧撑，Burpee俯卧撑]}，title =印度锻炼，类别=力量，长度= 1，目标=此锻炼可以完成by a BABUJI}，-KDnhRwHjssOejrqyenP = {weeks = {week1 = [High Knees，Jumping Jacks，Wall sit，Pushups，Sit-up，Step up，Squats，Tricep dips on chair，Plank，High Knees running in Lounges，俯卧撑和旋转，侧板（每轮交替），交替俯卧撑，胸部扩张器，钻石俯卧撑，潜水轰炸机俯卧撑，对接踢球器，躺式三头肌升降机，单臂侧俯卧撑，架空臂拍，架空压力机，动力圈，俯卧撑和旋转，T俯卧撑，反向木板，蜘蛛侠俯卧撑，T提升，三头肌下垂，俯卧撑，宽臂俯卧撑，Burpees]}，title = Hello锻炼，类别=力量，长度= 1，goal =这项训练可以在手机上完成！}}
03-28 08：52：53.967 23584-23584 / com.android.sam I / System.out: {-KDnfjROKeFAL9wccsxY = {weeks = {week1 = [High Knees，Squats，Lunges，Diamond Push-up，Lying] Triceps Lifts]}，title = Afternoon HiiT，category = Mobility，length = 1，goal = afternoon body weight workout}， - KDps90Dn6XtJc6Co00b = {weeks = {week1 = [Diamond Pushups，Jackknives，Plyo Lunges，Plyo Squats，Single leg plank （每轮交替），Plyo Lunges，俯卧撑和旋转，加权侧板（每轮交替），交替俯卧撑，胸部扩张器，钻石俯卧撑，潜水轰炸机俯卧撑，单臂侧俯卧撑，架空按下，俯卧撑和旋转，T俯卧撑，蜘蛛侠俯卧撑，宽臂俯卧撑，Burpee俯卧撑]}，标题=标题，类别=力量，长度= 1，目标=目标}}
Program.java
public class Program {
private String title;
private String goal;
private String category;
private int length;
HashMap<String, ArrayList<String>> weeks;
/**
* Required public constructor
*/
public Program() {
}
public Program(String title, String goal, String category, int length, HashMap<String, ArrayList<String>> weeks) {
this.title = title;
this.goal = goal;
this.category = category;
this.length = length;
this.weeks = weeks;
}
public String getTitle() {
return title;
}
public String getGoal() {
return goal;
}
public String getCategory() {
return category;
}
public int getLength() {
return length;
}
public HashMap<String, ArrayList<String>> getweeks() {
return weeks;
}
}
答案 0 :(得分：3)
你快到了。您只需要添加1侦听器以及迭代浏览与引用节点关联的数据。这是一个如何完成它的例子。
在您的情况下，我们只需声明一个名为addListenerForSingleValueEvent
ProgramList现在获取对电子邮件地址节点的引用并为其添加一个侦听器。
public class ProgramList {
public List<Program> mProgramList;
}
您可以再次检查firebase documentation以检索android中的数据。 This is an example与您在此处拥有相同的数据库结构。
答案 1 :(得分：3)
正如@ReazMurshed所说，你几乎就在那里。但是你没有在树中迭代一个级别。似乎ref指向JSON中的subscriptions节点。在那之下你有用户，然后你有推动ID。所以你需要做一个双循环：
ref.addListenerForSingleValueEvent(new ValueEventListener) {
public void onDataChange(DataSnapshot snapshot) {
if (dataSnapshot.exists()) {
for (DataSnapshot userSnapshot : snapshot.getChildren()) {
for (DataSnapshot programSnapshot : userSnapshot.getChildren()) {
Program program = programSnapshot.getValue(Program.class);
}
}
}
public void onCancelled(FirebaseError firebaseError) {
}
});