I have an app with a recycler view as the first page you see, and based off which item you click, it should take you to a separate, more detailed page. The problem is that when it takes me to these separate pages, they are completely black, only showing the action bar title- even though there is content in the xml files. I'm very new to Kotlin and android development, so I would appreciate any type of help.
My Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.worthit">
<application
android:allowBackup="true"
android:dataExtractionRules="@xml/data_extraction_rules"
android:fullBackupContent="@xml/backup_rules"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.WorthIt"
tools:targetApi="31">
<activity
android:name=".DetailsAct"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".DetailsAct2"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".DetailsAct3"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".DetailsAct4"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".DetailsAct5"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".DetailsAct6"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".DetailsAct7"
android:exported="true"
android:parentActivityName=".MainActivity"/>
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
My RecyclerView.kt
package com.example.worthit
import android.app.Activity
import android.content.Context
import android.content.Intent
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import android.widget.ImageView
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.core.content.ContextCompat.startActivity
import androidx.recyclerview.widget.RecyclerView
class Recycler(var app:Context): RecyclerView.Adapter<Recycler.ViewHolder>() {
private var titles = arrayOf("Sunday", "Monday" ,"Tuesday" ,"Wednesday", "Thursday", "Friday", "Saturday")
private var details = arrayOf("SundayD", "MondayD","TuesdayD" ,"WednesdayD", "ThursdayD", "FridayD", "SaturdayD")
private var images = intArrayOf(R.drawable.everyday_photo, R.drawable.everyday_photo, R.drawable.everyday_photo, R.drawable.everyday_photo, R.drawable.everyday_photo, R.drawable.everyday_photo, R.drawable.everyday_photo)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): Recycler.ViewHolder {
val v = LayoutInflater.from(parent.context).inflate(R.layout.card_layout, parent, false)
return ViewHolder(v)
}
override fun getItemCount(): Int {
return titles.size
}
override fun onBindViewHolder(holder: Recycler.ViewHolder, position: Int) {
holder.itemTitle.text = titles[position]
holder.itemDetail.text = details[position]
holder.itemImage.setImageResource(images[position])
}
inner class ViewHolder(itemView: View): RecyclerView.ViewHolder(itemView){
var itemImage: ImageView
var itemTitle: TextView
var itemDetail : TextView
init {
itemImage = itemView.findViewById(R.id.item_image)
itemTitle = itemView.findViewById(R.id.item_title)
itemDetail = itemView.findViewById(R.id.item_detail)
itemView.setOnClickListener {
when(bindingAdapterPosition)
{
0 -> app.startActivity(Intent(app, DetailsAct::class.java))
1 -> app.startActivity(Intent(app, DetailsAct2::class.java))
2 -> app.startActivity(Intent(app, DetailsAct3::class.java))
3 -> app.startActivity(Intent(app, DetailsAct4::class.java))
4 -> app.startActivity(Intent(app, DetailsAct5::class.java))
5 -> app.startActivity(Intent(app, DetailsAct6::class.java))
6 -> app.startActivity(Intent(app, DetailsAct7::class.java))
}
}
}
}
}
My MainActivity.kt
package com.example.worthit
import android.content.Context
import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import android.widget.ImageView
import androidx.core.content.ContextCompat
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
class MainActivity : AppCompatActivity() {
private var layoutManager: RecyclerView.LayoutManager? = null
private var adapter: RecyclerView.Adapter<Recycler.ViewHolder>? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
layoutManager = LinearLayoutManager(this)
val recyclerView = findViewById<RecyclerView>(R.id.recyclerView)
recyclerView.layoutManager = layoutManager
adapter = Recycler(this)
recyclerView.adapter = adapter
}
}
One of my DetailsAct.kt(one of the more detailed pages, the second activity page)
package com.example.worthit
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.ImageView
import android.widget.TextView
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
class DetailsAct : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_details)
val actionBar = supportActionBar
if(actionBar != null)
{
actionBar.title = "SundayDetails"
actionBar.setDisplayHomeAsUpEnabled(true)
}
}
}
example content for details page
EDIT:
Details XML
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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="wrap_content"
android:layout_height="match_parent"
tools:context=".DetailsAct">
<TextView
android:id="@ id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="176dp"
android:layout_marginTop="351dp"
android:layout_marginEnd="177dp"
android:layout_marginBottom="361dp"
android:text="@string/sunday_text"
android:textColor="#F44336"
android:textSize="60sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.496"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0" />
<ImageView
android:id="@ id/details1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintBottom_toTopOf="@ id/text1"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.498"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.212"
tools:srcCompat="@tools:sample/avatars" />
<TextView
android:id="@ id/textd1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.498"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@ id/text1"
app:layout_constraintVertical_bias="0.313" />
</androidx.constraintlayout.widget.ConstraintLayout>
CodePudding user response：
If you can provide the xml code of the layout, it will be easier for everyone to help you.
If the screen is black, it may be because your mobile phone is in dark mode.
If the screen does not display the layout components you designed, please make sure the information you give to the components, such as the image source of the ImageView, the text of the TextView.
My guess
Your phone is in dark mode, your ImageView do not have any source, your TextView's text color is black, so you do not see anything.
Please try specifying the image source to ImageView(
android:src="@drawable/yourImage
)
and change the text color of the TextView to white(
android:textColor="@color/youColor"
)
CodePudding user response：
I'm not very clear your problem but you can consider a few things:
Make your constraint layout width match parent android:layout_width="match_parent".
Don't use wrap_content with Imageview, replace it by 0dp. Then you can set padding or margin horizontal to scale it.
Don't use tools:srcCompat, try android:src, example: android:src="@drawable/avatars". Don't forget to create an avatar resource in drawable folder.
Hope it will solve your problem.