I'm trying to add ActionBar-PushToRefresh to my project. I've followed the instructions from Chris Banes Github there: Github ActionBar-PullToRefresh
Here is my view from which I want to enable the PullToRefresh feature:
<uk.co.senab.actionbarpulltorefresh.library.PullToRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/ptr_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Your content, here we're using a ScrollView -->
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="PULLTOREFRESH THE VIEW"
android:id="#+id/textView1" />
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
</ScrollView>
</uk.co.senab.actionbarpulltorefresh.library.PullToRefreshLayout>
And here is my Activity to display the view:
package com.Test.pulltorefresh;
import android.app.Activity;
import android.os.Bundle;
import uk.co.senab.actionbarpulltorefresh.library.ActionBarPullToRefresh;
import uk.co.senab.actionbarpulltorefresh.library.Options;
import uk.co.senab.actionbarpulltorefresh.library.PullToRefreshLayout;
public class MainActivity extends Activity {
private PullToRefreshLayout mPullToRefreshLayout;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Now find the PullToRefreshLayout to setup
mPullToRefreshLayout = (PullToRefreshLayout) findViewById(R.id.ptr_layout);
// Now setup the PullToRefreshLayout
ActionBarPullToRefresh.from(this)
// Mark All Children as pullable
.allChildrenArePullable()
// Set the OnRefreshListener
//.listener(this)
// Finally commit the setup to our PullToRefreshLayout
.setup(mPullToRefreshLayout);
}
}
When I launch my app, I got the blank view but nothing happens when I'm trying to PushToRefresh my view. Can someone show me how to fix it, I know that I've missed something. Thanks.
I may be a bit partial but...
you could consider using this
Maybe you have already achieved the functionality, but in the code above, you have commented out the line which defines the action on pulling the view.
//.listener(this)
You should uncomment this line and define the listener method, which should be called when the view is pulled.
Related
I create an app using binding and I get an error that I couldn't solve.
The error is
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.newtest/com.example.mylibrary.MainActivity1}: java.lang.NullPointerException: Missing required view with ID: com.example.newtest:id/myRecyclerview
Thanks!
public class MainActivity1 extends AppCompatActivity {
RecyclerView.LayoutManager layoutManager;
ArrayList<POJOimage>pojoImageArrayList;
ActivityMainBinding binding;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = ActivityMainBinding.inflate(getLayoutInflater());
setContentView(binding.getRoot());
layoutManager = new LinearLayoutManager(this);
binding.myRecyclerview.setLayoutManager(layoutManager);
init();
}
XML:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity1"
android:background="#000"
android:padding="10dp">
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/myRecyclerview"/>
</androidx.constraintlayout.widget.ConstraintLayout>
I strongly suspect some Android Studio bug.
I had the same bug, and everything I've had done was adding some TextView.
As it was easy to find this difference, I've just started fiddling with this TextView in xml. At some point bug disappeared.
And here comes the best. Before starting to deal with the problem I've saved problematic change with git. So at the end I've reapplied this change and ... everything worked. No more bug !
P.S. As this bug reappears, I've found that the easiest solution for getting rid of it is to use "Clean Project" from "Build" menu.
I am doing a java to c# transition, and need help.
in Visual Studio 2019 Pro, Android 9.0 (Pie), I am doing this example:
https://learn.microsoft.com/en-us/xamarin/android/platform/binding-java-library/binding-a-jar
The goal is later to convert my java libs to c# for my big project.
I follow the instructions to the letter, and when I come to the part where I need to create an ImageView, there is the problem. Once I create the ImageView, it has an android:src field, something like this (auto generated):
android:src="#drawable/icon"
The problem here, is when I remove that field, in the VS designer, the ImageView disappears and it does not matter if I have the c# code or not, even when I set the srec to:""
Bellow is literally all the code in MainActivity:
using Android.App;
using Android.OS;
using Android.Support.V7.App;
using Android.Runtime;
using Android.Widget;
using Com.Squareup.Picasso;
namespace App3
{
[Activity(Label = "#string/app_name", Theme = "#style/AppTheme", MainLauncher = true)]
public class MainActivity : AppCompatActivity
{
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
Xamarin.Essentials.Platform.Init(this, savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.activity_main);
/***********************************************************************/
/**Picasso Code**/
ImageView imageView = FindViewById<ImageView>(Resource.Id.imageView1);
// Use the Picasso jar library to load and display this image:
Picasso.With(this)
.Load("http://i.imgur.com/DvpvklR.jpg")
.Into(imageView);
/**End Ff Picasso Code**/
/***********************************************************************/
}
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);
base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
}
XML Code:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:minWidth="25px"
android:minHeight="25px">
<ImageView
android:src="#drawable/icon" <!-- this line -->
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/imageView1" />
</LinearLayout>
The app does nothing, and in the emulator, the ImageView is empty.
And there is no error, or anything.
If you need anything more, please let me know.
I hope you can help me, if not, thank you for your time.
Edit 1:
It seems, the problem lies in the C# code.
If I add the android:src field, it still does not show up on the emulator, but when I remove the code (the Picasso code) than the image(drawable/icon) shows. Still no error!!
try this
<ImageView
android:src="#drawable/icon" <!-- this line -->
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minWidth="50px"
android:minHeight="50px"
android:id="#+id/imageView1" />
The following classes could not be instantiated:
- com.amazon.device.ads.AdLayout (Open Class, Show Error Log)
See the Error Log (Window > Show View) for more details.
Tip: Use View.isInEditMode() in your custom views to skip code when shown in Eclipse
java.lang.NoClassDefFoundError: Could not initialize class android.os.Environment
at com.amazon.device.ads.DebugProperties.readDebugProperties(DebugProperties.java:75)
at com.amazon.device.ads.InternalAdRegistration.<init>(InternalAdRegistration.java:52)
at com.amazon.device.ads.InternalAdRegistration.getInstance(InternalAdRegistration.java:64)
at com.amazon.device.ads.AdLayout.initialize(AdLayout.java:185)
at com.amazon.device.ads.AdLayout.initialize(AdLayout.java:176)
at com.amazon.device.ads.AdLayout.<init>(AdLayout.java:120)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0( at sun.reflect.NativeConstructorAccessorImpl.newInstance( at sun.reflect.DelegatingConstructorAccessorImpl.newInstance( at java.lang.reflect.Constructor.newInstance( at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.instantiateClass(ProjectCallback.java:422)
at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.loadView(ProjectCallback.java:179)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:207)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:135)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:755)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:727)
at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
at android.view.LayoutInflater.inflate(LayoutInflater.java:373)
My main.xml looks like this
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:Amazon="http://schemas.android.com/apk/lib/com.amazon.device.ads"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="top|center_horizontal" >
<com.amazon.device.ads.AdLayout
android:id="#+id/myAdView"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
My MainActivity.java is this
import com.amazon.device.ads.AdLayout;
import com.amazon.device.ads.AdRegistration;
import com.amazon.device.ads.AdTargetingOptions;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
preferences = PreferenceManager.getDefaultSharedPreferences(this);
int defaultValue = R.drawable.blue;
int themedefault = ThemeChanger.THEME_BLUE;
appliedtheme = preferences.getInt("mytheme", themedefault);
ThemeChanger.onActivityCreateSetTheme(this, appliedtheme);
setContentView(R.layout.main);
AdRegistration.setAppKey("Application_Key");
this.adView = (AdLayout) findViewById(R.id.myAdView);
this.adView.loadAd(new AdTargetingOptions());
button1 = preferences.getInt("DigitButtonStyle", defaultValue);
buttonmadd = preferences.getInt("MemoryButtonStyle", defaultValue);
buttoncos = preferences.getInt("FunctionButtonStyle", defaultValue);
I had the same issue and followed Amazon developer guide. To solve this issue, just copy amazon library and paste it in your libs folder and than run.
It's a known issue in Eclipse ADT plugin, even if you use View.isInEditMode(), in some cases, it crashes in recent API versions (higher than 18). It's fixed in Android Studio.
If you want to see Layout Preview, you can try with different API version lower than 19.
Check the screenshot. It's using API 18. (Red box is Amazon AdLayout)
This code and minor variations thereof exist in many forums on the net. When I launch it on my Samsung Galaxy Tab 2 (Android 4.1.1), the bar appears, the thumb can be moved, the position is reported, etc. All good, EXCEPT, the thumb never disappears. Mine manifests as a little blue circle, which I can slide along a bar, but it leaves a trail of "thumbs" behind it: one at each of the possible integer locations in the range of the seekbar.
Is the code incomplete? Is there something we have to add to manually redraw the component?
import android.app.Activity;
import android.os.Bundle;
import android.widget.SeekBar;
import android.widget.TextView;
public class FullscreenActivity
extends Activity
implements SeekBar.OnSeekBarChangeListener {
SeekBar seekBar;
TextView textView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fullscreen);
seekBar=(SeekBar)findViewById(R.id.seekbar);
textView=(TextView)findViewById(R.id.textview);
seekBar.setOnSeekBarChangeListener(this);
}
#Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// Notify that the progress level has changed.
textView.setText(textView.getText()+"\n"+"SeekBar now at the value of:"+progress);
}
#Override
public void onStartTrackingTouch(SeekBar seekBar) {
// placeholder
}
#Override
public void onStopTrackingTouch(SeekBar seekBar) {
// placeholder
}
}
Here's the layout:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/FrameLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<SeekBar
android:id="#+id/seekbar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="75dp"
android:max="31"
android:progress="15" />
<TextView
android:id="#+id/textview"
android:layout_width="fill_parent"
android:layout_height="270dp"
android:layout_marginTop="150dp"
android:scrollbarStyle="insideOverlay"
android:scrollbars="vertical" />
</FrameLayout>
Screenshot of the effect:
Update The effect is the same on a ZTE-BLADE running Android 2.2. Of course teh default graphic is different (the gray / orange seekbar with a more square "thumb") but the thumbs remain behind at all the points I've scrolled through.
The residual garbage clears if I change the screen orientation, which makes me think it just needs a redraw. Can anyone help?
So, I copied and pasted my example code line-at-a-time into a new project, running it as I went, hoping to find the line which failed.
Got the whole thing pasted in and it worked perfectly. No problems in the seekbar.
On comparing the projects, the only difference was that the AndroidManifest.XML file contained the line
android:theme="#style/FullscreenTheme"
in the activity section. So, I went back to my original (faulty) project and took this line out. Now the project works fine.
I have my answer: the code is complete and there's nothing we need to add to make it redraw.
I still don't understand why this line had that effect and now I have a horrible white background when I wanted black.
package com.example.one;
import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity {
Button button;
TextView txt1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addListenerOnButton();
}
public void addListenerOnButton(){
button=(Button)findViewById(R.id.button1);//error line of code
txt1=(TextView)findViewById(R.id.txt);//error line of code
button.setOnClickListener(
new View.OnClickListener()
{
public void onClick(View view)
{
txt1.setText("hello");
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
I have marked the error code of lines but unable to resolve
the .xml is
<EditText
android:id="#+id/txt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="26dp"
android:layout_marginTop="26dp"
android:ems="10"
android:inputType="text" >
<requestFocus />
</EditText>
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/txt"
android:layout_below="#+id/txt"
android:layout_marginLeft="18dp"
android:layout_marginTop="110dp"
android:text="Button -MYBUT" />
I just want to add a button and a textview in my app beacuse I'm a beginner Android Developer so unable to resolve my issue thanks in advance
Try to use findViewById after you inflate your menu. You are trying to find an element in a view that has not yet be attached to the activity.
This is just fine, check your imports. In android are 2 types of R present.
- R Generated, by your project builder
- R brought by android sdk
I guess that you imported R from android SDK, not generated by your project. That's why eclipse yells with errors at you.
The other situation is, that, the findViewById() method called OnCreateOptionsMenu() callback is trying to reach view that has not been created yet, and returns null.
EDIT. Problems with R might be also associated with weird, not visible and hard to find mistakes in your xml files. When you make huge mistake in some of your xml files, builder returns error and R will not be generated. But in some cases, builder cant find any of your mistakes, but is not generating new R class - this causes your R to be out of date.
I just want to know that about the explanation of this line
but = (Button) findViewById(R.id.but);
findViewById(Id) returns a View and you have to cast that View to whatever UI element you are using.
In order for findViewById(Id) to return a View, you have to assign an Id to each UI element (if you want to use it in java):
<Button
android:id="#+id/myButtonId"
[...]
/>
Now you can do this:
but = (Button) findViewById(R.id.myButtonId);
You should also use the onCreate() method to initialize your UI elements, and not onCreateOptionsMenu().
Eclipse is a Curse try to not use it guys I Prefer NetBeans I love NetBeans so much Hats off for NetBeans!
The Answer of my own Question:
it was a real time fault of my eclipse (a curse) not my fault. The Solution is to restart the IDE or to press the Save All from File Menu of IDE
Visit: https://stackoverflow.com/a/7453201/2277645