使用 linearlayout.addView() 添加到线性布局的视图在运行时不会保持其顺序

Question

在Android中，使用linearlayout.addView((添加到线性布局的视图在运行时不会保持顺序，在不同的运行和点击中顺序不断变化，并且没有特定的顺序。每当我尝试刷新时，顺序都会发生变化，这非常令人恼火，我找不到任何解决方案。请帮忙。 在 Android 中，使用 linearlayout.addView(( 添加到 linearlayout 的视图在运行时不会保持顺序。，顺序在不同的运行和点击中不断变化，并且没有特定的顺序。每当我尝试刷新时，顺序都会发生变化，这非常令人恼火，我找不到任何解决方案。请帮忙。 在 Android 中，使用 linearlayout.addView(( 添加到 linearlayout 的视图在运行时不会保持顺序。，顺序在不同的运行和点击中不断变化，并且没有特定的顺序。每当我尝试刷新时，顺序都会发生变化，这非常令人恼火，我找不到任何解决方案。请帮忙

Package com.example.instagramclone;

import android.app.ProgressDialog;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.Log;
import android.view.Gravity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import com.parse.FindCallback;
import com.parse.GetCallback;
import com.parse.GetDataCallback;
import com.parse.ParseException;
import com.parse.ParseFile;
import com.parse.ParseObject;
import com.parse.ParseQuery;
import com.parse.ParseUser;
import com.shashank.sony.fancytoastlib.FancyToast;
import java.text.SimpleDateFormat;
import java.util.List;
public class usersPost extends AppCompatActivity {
private LinearLayout linearLayout;
private String receivedUserName;
LinearLayout rootlayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_users_post);
linearLayout = (LinearLayout) findViewById(R.id.linearLayout);
//        rootlayout = (LinearLayout) findViewById(R.id.rootlayout);
Intent receivedIntentObject = getIntent();
receivedUserName = receivedIntentObject.getStringExtra("username");
FancyToast.makeText(this, receivedUserName, FancyToast.LENGTH_SHORT,
FancyToast.INFO, true).show();
setTitle(receivedUserName + "'s posts");
final ProgressDialog dialog = new ProgressDialog(this);
dialog.setMessage("Loading...");
dialog.show();
//        if (linearLayout.getChildCount() > 0)
//            linearLayout.removeAllViews();
displayprofilepic();
diaplayprofilename();
displayposts();
dialog.dismiss();
}
public void displayprofilepic()
{
//for displaying profile picture first
try {
final ParseQuery<ParseUser> parseUser = ParseUser.getQuery();
parseUser.whereEqualTo("username", receivedUserName);
parseUser.findInBackground(new FindCallback<ParseUser>() {
@Override
public void done(List<ParseUser> objects, ParseException e) {
if (objects.size()>0 && e == null) {
ParseFile parseFile = objects.get(0).getParseFile("profilepicture");
if (parseFile != null) {
TextView textView = new TextView(usersPost.this);
textView.setText("Profile Picture:");
linearLayout.addView(textView);
parseFile.getDataInBackground(new GetDataCallback() {
@Override
public void done(byte[] data, ParseException e) {
if (data != null && e == null) {
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
ImageView postImageView = new ImageView(usersPost.this);
LinearLayout.LayoutParams imageview_params = new LinearLayout.LayoutParams(1000, 1000);
imageview_params.setMargins(5, 5, 5, 5);
postImageView.setLayoutParams(imageview_params);
postImageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
postImageView.setImageBitmap(bitmap);
linearLayout.addView(postImageView);

}
}
});
} else {
TextView textView = new TextView(usersPost.this);
textView.setText("Profile Picture:");
linearLayout.addView(textView);
ImageView postImageView = new ImageView(usersPost.this);
LinearLayout.LayoutParams imageview_params = new LinearLayout.LayoutParams(500, 500);
imageview_params.setMargins(5, 5, 5, 5);
postImageView.setLayoutParams(imageview_params);
postImageView.setScaleType(ImageView.ScaleType.FIT_START);
postImageView.setImageResource(R.drawable.empty_profile_pic);
linearLayout.addView(postImageView);

}
}
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
public void diaplayprofilename()
{
/////////profile name
ParseQuery<ParseUser> parseUser = ParseUser.getQuery();
parseUser.whereEqualTo("username", receivedUserName);
parseUser.getFirstInBackground(new GetCallback<ParseUser>() {
@Override
public void done(ParseUser object, ParseException e) {
if (object != null && e == null) {
TextView name = new TextView(usersPost.this);
name.setText(object.get("profileName") + "");
LinearLayout.LayoutParams txt_params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
txt_params.setMargins(5, 5, 5, 50);
name.setLayoutParams(txt_params);
name.setGravity(Gravity.CENTER);
name.setBackgroundResource(R.drawable.txtview_bg);
name.setTextColor(Color.BLACK);
name.setTextSize(20f);
linearLayout.addView(name);
}
}
});
}
public void displayposts()
{
/////////////////
try {
final ParseQuery<ParseObject> parseQuery = new ParseQuery<ParseObject>("photo");
parseQuery.whereEqualTo("username", receivedUserName);
parseQuery.orderByDescending("createdAt");

parseQuery.findInBackground(new FindCallback<ParseObject>() {
@Override
public void done(List<ParseObject> objects, ParseException e) {
if (objects.size() > 0 && e == null) {
for (ParseObject post : objects) {
final String s = (post.get("caption") != null) ? post.get("caption") + "" : "";
SimpleDateFormat formatter = new SimpleDateFormat("dd MMMM yyyy");
// formatter.setTimeZone(TimeZone.getTimeZone("IST"));
final String dt = formatter.format(post.getCreatedAt());
Log.i("data", dt);
ParseFile postpicture = (ParseFile) post.get("picture");
postpicture.getDataInBackground(new GetDataCallback() {
@Override
public void done(byte[] data, ParseException e) {
if (data != null && e == null) {
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
ImageView postImageView = new ImageView(usersPost.this);
LinearLayout.LayoutParams imageview_params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
imageview_params.setMargins(0, 5, 145, 5);
postImageView.setLayoutParams(imageview_params);
postImageView.setPadding(15, 0, 15, 0);
postImageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
postImageView.setBackgroundResource(R.drawable.imgview_bg);
Drawable d = new BitmapDrawable(getResources(), bitmap);
//postImageView.setImageBitmap(bitmap);
postImageView.setImageDrawable(d);
linearLayout.addView(postImageView);
TextView date = new TextView(usersPost.this);
date.setText(dt);
LinearLayout.LayoutParams dt_params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
dt_params.setMargins(5, 5, 5, 50);
date.setLayoutParams(dt_params);
date.setGravity(Gravity.START);
date.setBackgroundResource(R.drawable.txtview_bg);
date.setTextColor(Color.BLACK);
date.setTextSize(15f);
linearLayout.addView(date);
TextView caption = new TextView(usersPost.this);
caption.setText(s);
LinearLayout.LayoutParams des_params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
des_params.setMargins(5, 5, 5, 50);
caption.setLayoutParams(des_params);
caption.setGravity(Gravity.CENTER);
caption.setBackgroundResource(R.drawable.txtview_bg);
caption.setTextColor(Color.BLUE);
caption.setTextSize(20f);
linearLayout.addView(caption);
}
}
});
}
} else {
FancyToast.makeText(usersPost.this, "No Posts!!",
FancyToast.LENGTH_SHORT, FancyToast.INFO, true).show();
//finish();
//                            LinearLayout linearLayout1 =
//                                    (LinearLayout) findViewById(R.id.rootlayout);
TextView textView = new TextView(usersPost.this);
textView.setGravity(Gravity.CENTER);
textView.setTextSize(25);
//textView.setScaleX(0.5f);
textView.setText(receivedUserName + " has no posts");
linearLayout.addView(textView);

}
}
});
}catch (Exception e){
e.printStackTrace();
}
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menuchat,menu);
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item) {
if(item.getItemId()==R.id.chatItem)
{
Intent intent = new Intent(usersPost.this,ChatActivity.class);
intent.putExtra("username",receivedUserName);
startActivity(intent);
}
return super.onOptionsItemSelected(item);
}
}

我的 XML 代码如下：

<?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:id="@+id/rootlayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".usersPost"
android:orientation="vertical">
<ScrollView
android:layout_width="409dp"
android:layout_height="0dp"
android:layout_weight="2.7"
tools:layout_editor_absoluteX="1dp"
tools:layout_editor_absoluteY="1dp"
>
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" />
</ScrollView>
</LinearLayout>

Answer 1

你不会将位置传递给 addView((。作为第二个参数，您可以传递添加的视图的位置，例如addView(按钮，2(。

Answer 2

你调用displayprofilepic()、diaplayprofilename()和displayposts()3 方法调用asynchronous这也意味着done回调asynchronous。 当您添加视图时，它不会保持顺序。您应该先呼叫displayprofilepic，完成后调用diaplayprofilename依此类推displayposts