Develop Reference

Unable to access view to change background color

I am building a simple list view that is taking in a series of detected items and adding them to a list. I want to be able to change the color of these views when I click on them. However, I am struggling with creating a way to access the individual view so that I can change its color. This code is based off Android Studio Sample BluetoothLeGatt. I have tried looking at places like here to no avail.
Class adding detected device to the list
private class LeDeviceListAdapter extends BaseAdapter {
private ArrayList<BluetoothDevice> mLeDevices;
private LayoutInflater mInflator;
public LeDeviceListAdapter() {
super();
mLeDevices = new ArrayList<BluetoothDevice>();
mInflator = DeviceScanActivity.this.getLayoutInflater();
}
public void addDevice(BluetoothDevice device) {
if (!mLeDevices.contains(device)) {
mLeDevices.add(device);
}
}
public BluetoothDevice getDevice(int position) {
return mLeDevices.get(position);
}
public void clear() {
mLeDevices.clear();
}
#Override
public int getCount() {
return mLeDevices.size();
}
#Override
public Object getItem(int i) {
return mLeDevices.get(i);
}
#Override
public long getItemId(int i) {
return i;
}
#Override
public View getView(int i, View view, ViewGroup viewGroup) {
ViewHolder viewHolder;
// General ListView optimization code.
if (view == null) {
view = mInflator.inflate(R.layout.listitem_device, null);
viewHolder = new ViewHolder();
viewHolder.deviceAddress = (TextView) view.findViewById(R.id.device_address);
viewHolder.deviceName = (TextView) view.findViewById(R.id.device_name);
view.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) view.getTag();
}
BluetoothDevice device = mLeDevices.get(i);
final String deviceName = device.getName();
if (deviceName != null && deviceName.length() > 0) {
viewHolder.deviceName.setText(deviceName);
} else {
viewHolder.deviceName.setText(R.string.unknown_device);
}
viewHolder.deviceAddress.setText(device.getAddress());
return view;
}
}
OnListClick Code
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
final BluetoothDevice device = mLeDeviceListAdapter.getDevice(position);
if (device == null) return;
getListView().getItemAtPosition(position);
//change background color here.
}
Here I supposedly able to access the individual elements with getListView().getItemAtPosition(position); but I don't know how to use this to change the background color since it doesn't provide me access to the view itself.
XML for ViewList
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView android:id="#+id/device_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="24sp"/>
<TextView android:id="#+id/device_address"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="12sp"/>
</LinearLayout>
If anyone could suggest a way to alter Android Studio's implementation I would greatly appreciate it. I am trying to use this code due to my unfimiliarity with Android Development.

OnListClick Code you have (view v)
Using this v you can access properties related to clicked view.

You are getting View parameter at second in this method
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
v.setBackgroundColor(Color.parseColor("#ffffff"));
}
If you want change onTouch color the use this
Make a bg.xml in your drawable folder.
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_focused="true" android:state_pressed="true"
android:drawable="#drawable/bgalt" />
<item android:state_focused="false" android:state_pressed="true"
android:drawable="#drawable/bgalt" />
<item android:drawable="#drawable/bgnorm" />
</selector>
Set this drawable to parent layout element
<LinearLayout
background="#drawable/bg"
clickable="true"
...>
</LinearLayout>

How to display the actual image onclick from gridview

I'm trying to get the image in the chat box when I click on any of the images from the gridview however, whenever I try to do so it comes up with a text, so please advise what can be done to get the image itself instead of the text that is appearing, please help me out I've been stuck for too long
smiles_items_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView android:id="#+id/smile_image_view"
android:layout_width="45dp"
android:layout_height="45dp"
android:layout_gravity="center"/>
</LinearLayout>
BottomSheetDialog_Smiles.java
public class ImageAdapter2 extends BaseAdapter {
private Context mContext;
private final int[] mThumbIds;
String[] mThumbIdsString = null;
public ImageAdapter2(Context c, int[] mThumbIds , String[] mThumbIdsString)
{
mContext = c;
this.mThumbIds = mThumbIds;
this.mThumbIdsString = mThumbIdsString;
}
#Override
public int getCount() {
return mThumbIds.length & mThumbIdsString.length;
}
#Override
public Object getItem(int position) {
return position;
}
#Override
public long getItemId(int position) {
return position;
}
public class Holder {
ImageView img;
}
#Override
public View getView(final int position, final View convertView,
ViewGroup parent) {
final Holder holder = new Holder();
LayoutInflater inflater = (LayoutInflater)
getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
grid = inflater.inflate(R.layout.smiles_items_layout, null);
null);
holder.img = (ImageView) grid.findViewById(R.id.smile_image_view);
holder.img.setImageResource(mThumbIds[position]);
gridView2.setOnItemClickListener(new
AdapterView.OnItemClickListener() {
Drawable drawable;
#Override
public void onItemClick(AdapterView<?> adapterView, View view,
int i, long l) {
JSONDictionary imageChat = new JSONDictionary();
LinearLayout layout= (LinearLayout)view;
ImageView imageView = (ImageView) layout.getChildAt(0);
imageView.getDrawable();
imageChat.put("message", imageView);
Communicator.getInstance().emit("new chat message",
imageChat);
}
});
return grid;
}
}
This is the result which appears when clicking on the image

Do you need an ImageView inside an image?
I used this code to get an image.
Send your view this method get as image.
protected Bitmap ConvertToBitmap(ImageView image_view) {
Bitmap map;
image_view.setDrawingCacheEnabled(true);
image_view.buildDrawingCache();
return map=image_view.getDrawingCache();
}
In ur adapter code
holder.img.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Bitmap b = ConvertToBitmap(holder.img);;
//now get bitmap used to assign
imageChat.put("message", b);
Communicator.getInstance().emit("new chat message",
imageChat);
}
});

Android: Slider image viewPager is not showing anything

I have seen all the question related to this topic but didn't find solution, in my case viewpager is not showing anything, its simple image slider, moreover toast are appearing as i'm swaping but didn't see image and text, and when im adding these lines(as other solutions said)
((ViewPager) container).addView(iv, 0);
((ViewPager) container).addView(tv, 0);
it gives me error
android.support.v4.view.ViewPager$LayoutParams cannot be cast to android.view.ViewGroup$MarginLayoutParams
this is my main.xml file (inside relative layout):
<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/view_pager"/>
this is viewPager adapter
public class ClsCustomPagerViewAdapter extends PagerAdapter {
int[] layouts;
String[] titles;
LayoutInflater layoutInflater;
Context context;
public ClsCustomPagerViewAdapter(Context context, int[] layouts,
String[] titles) {
this.layouts = layouts;
this.titles = titles;
this.context = context;
layoutInflater = LayoutInflater.from(context);
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((ViewGroup) object);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
View imageLayout = layoutInflater.inflate(R.layout.image_placeholder
, container);
TextView tv = (TextView) imageLayout.findViewById(R.id.tv);
ImageView iv = (ImageView) imageLayout.findViewById(R.id.iv);
Toast.makeText(context,
"Viewpagers " + titles[position] ,
Toast.LENGTH_SHORT).show();
tv.setText(titles[position]);
iv.setImageResource(layouts[position]);
((ViewPager) container).addView(iv, 0);
((ViewPager) container).addView(tv, 0);
return imageLayout;
}
#Override
public int getCount() {
return layouts.length;
}
#Override
public boolean isViewFromObject(View view, Object object) {
return view.equals(object);
}
and this is layout for images and textviews for viewpager adapter(inside framelayout)
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/tv"
android:text="Hello world"
android:gravity="center_horizontal"
android:layout_marginTop="20dp"
android:layout_alignTop="#+id/iv"
android:layout_alignBottom="#+id/iv"
android:layout_alignLeft="#+id/iv"
android:layout_alignRight="#+id/iv"/>
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/iv"
/>

Replace these two lines of code
((ViewPager) container).addView(iv, 0);
((ViewPager) container).addView(tv, 0);
with
container.addView(imageLayout);
EDITED:
Also
View imageLayout = layoutInflater.inflate(R.layout.image_placeholder
, container);
with
View imageLayout = layoutInflater.inflate(R.layout.image_placeholder
, container, false);

How to get the run time image id to set wallpaper

I am using view paper for image gallery, able to see all the images on swipe.
Here I want to set the image as wallpaper by clicking the "Set as wallpaper" button.
Below are the difficulties I am facing:
I am able to set the image as wallpaper successfully, but with constant image
Ex: R.drawable.picture3.But at run time when the images are loaded at each
turn different image will be displayed so cannot give this constant value
R.drawable.picture3.
How do I get the run time image id which is displayed?
Trying to achieve on click "Set as wallpaper" should set the current image
as wallpaper.
Note : v.getId()=R.drawable.picture1 not worked here both gave different value
Below is my code:
Context context;
Integer[] imageIDs = {
R.drawable.picture1,
R.drawable.picture2,
R.drawable.picture3,
R.drawable.picture4,
R.drawable.picture5,
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gallery);
ViewPager viewPager = (ViewPager) findViewById(R.id.pager);
ImageAdapter adapter = new ImageAdapter(this);
viewPager.setAdapter(adapter);
Button button=(Button) findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
WallpaperManager wallpaperManager = WallpaperManager.getInstance(getApplicationContext());
try {
wallpaperManager.setResource(R.drawable.picture3);
} catch (IOException e) {
e.printStackTrace();
}
Toast.makeText(getApplicationContext(),
"Image is clicked-"+v.getBackground(), Toast.LENGTH_SHORT).show();
}
});
}
public class ImageAdapter extends PagerAdapter{
Context context;
int currentPosition;
private int[] GalImages = new int[] {
R.drawable.picture1,
R.drawable.picture2,
R.drawable.picture3,
R.drawable.picture4,
R.drawable.picture5,
};
ImageAdapter(Context context){
this.context=context;
}
#Override
public int getCount() {
return GalImages.length;
}
#Override
public boolean isViewFromObject(View view, Object object) {
return view == ((ImageView) object);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
ImageView imageView = new ImageView(context);
int padding = context.getResources().getDimensionPixelSize(R.dimen.abc_action_bar_content_inset_material);
imageView.setPadding(padding, padding, padding, padding);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setImageResource(GalImages[position]);
((ViewPager) container).addView(imageView, 0);
return imageView;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
((ViewPager) container).removeView((ImageView) object);
}
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
android:orientation="vertical"
>
<android.support.v4.view.ViewPager
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true">
</android.support.v4.view.ViewPager>
<Button
android:id="#+id/button1"
android:layout_width="match_parent"
android:layout_height="30dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:background="#cccccc"
android:text="#string/set_as_wallpaper" />
</RelativeLayout>
I don't want to achieve this in instantiateItem method in image adapter.

It's simple.If I got it correct then you want to set the image as wallpaper after clicking the button.Then here is the logic
viewPager.setOnPageChangeListener(new OnPageChangeListener() {
#Override
public void onPageSelected(int arg0) {
// TODO Auto-generated method stub
curruntPosition=arg0; //Here you can the position
}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
#Override
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
});
And then
button.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
WallpaperManager wallpaperManager = WallpaperManager.getInstance(getApplicationContext());
try {
wallpaperManager.setResource(imageIDs[curruntPosition]);
} catch (IOException e) {
e.printStackTrace();
}
Toast.makeText(getApplicationContext(),
"Image is clicked-"+v.getBackground(), Toast.LENGTH_SHORT).show();
}
});
Edit:
If you want to get the current viewable image from the viewpager
Maintain a list of images that are added dynamically say imageList then
int currentItem =viewPager.getCurrentItem();
Drawable drawable = getResource.getDrawable(imageList[currentItem]);
Bitmap bm =((BitmapDrawable) drawable).getBitmap();

How to display fancy frame on the image in android viewpager/imageview?

I have developed an app that is suppose to display images located in the drawable folder. I used imageview/viewpager for it. However, I would like to display frame shown below.On the top of the image so that image appears more fancy.. Also, the frame should swipe along with the image...so that it looks more beautiful... I was thinking of creating it permanently on the image...through photoshop... But I didn't like that idea ..So I thought may be android have something for it....I am android beginner...So any code help along with explanation will be appreciated..Following are my codes..
Mainactivity.java
import android.app.Activity;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
public class MainActivity extends Activity {
MediaPlayer oursong;
ViewPager viewPager;
ImageAdapter adapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
oursong = MediaPlayer.create(MainActivity.this, R.raw.a);
oursong.seekTo(0);
oursong.start();
viewPager = (ViewPager) findViewById(R.id.view_pager);
adapter = new ImageAdapter(this);
viewPager.setAdapter(adapter);
viewPager.setOnPageChangeListener(MyViewPagerListener);
}
private int pos = 0;
#Override
protected void onPause() {
super.onPause();
if(oursong != null){
pos = oursong.getCurrentPosition();
oursong.release();
oursong = null;
}
}
#Override
protected void onResume(){
super.onResume();
oursong = MediaPlayer.create(MainActivity.this, R.raw.a);
oursong.seekTo(pos); // You will probably want to save an int to restore here
oursong.start();
}
private final OnPageChangeListener MyViewPagerListener = new OnPageChangeListener() {
#Override
public void onPageSelected(int pos) {
if (pos == adapter.getCount() - 1){
// adding null checks for safety
if(oursong != null){
oursong.pause();
}
} else if (!oursong.isPlaying()){
// adding null check for safety
if(oursong != null){
oursong.start();
}
}
}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
#Override
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
};
}
Imageadapter.java
import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
public class ImageAdapter extends PagerAdapter {
Context context;
private int[] GalImages = new int[] {
R.drawable.one,
R.drawable.two,
R.drawable.three,
R.drawable.four,
R.drawable.five
};
ImageAdapter(Context context){
this.context=context;
}
#Override
public int getCount() {
return GalImages.length;
}
#Override
public boolean isViewFromObject(View view, Object object) {
return view == ((ImageView) object);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
ImageView imageView = new ImageView(context);
int padding = context.getResources().getDimensionPixelSize(R.dimen.padding_small);
imageView.setPadding(padding, padding, padding, padding);
imageView.setScaleType(ImageView.ScaleType.FIT_XY);
imageView.setImageResource(GalImages[position]);
((ViewPager) container).addView(imageView, 0);
return imageView;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
((ViewPager) container).removeView((ImageView) object);
}
}
activity_main.xml
<RelativeLayout 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=".MainActivity"
android:icon="#drawable/icon" >
<android.support.v4.view.ViewPager
android:id="#+id/view_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:icon="#drawable/icon" />
<ImageView
android:id="#+id/swipe_left"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:src="#drawable/swipe_left" />
<ImageView
android:id="#+id/swipe_right"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:src="#drawable/swipe_right" />
</RelativeLayout>
Edited
Hidden portion of the image under frame

You can do it using a LayerDrawable
A Drawable that manages an array of other Drawables. These are drawn
in array order, so the element with the largest index will be drawn on
top.
You have two choices to use LayerDrawable.You can either define it in a separate drawable xml and then simply set the image in your ImageView, or you can configure a LayerDrawable dynamically in your code.
Programmatically using code
Resources r = getResources();
Drawable[] layers = new Drawable[2];
layers[0] = r.getDrawable(R.drawable.yourImage);;
layers[1] = r.getDrawable(R.drawable.yourFrame);
LayerDrawable layerDrawable = new LayerDrawable(layers);
imageView.setImageDrawable(layerDrawable);
Now you have your ImageView having two images(1.your image and 2.Frame) set on it.
Edit :
In your ImageAdapter, you need to modify instantiateItem(ViewGroup container, int position) something like
#Override
public Object instantiateItem(ViewGroup container, int position) {
ImageView imageView = new ImageView(context);
int padding = context.getResources().getDimensionPixelSize(R.dimen.padding_small);
imageView.setPadding(padding, padding, padding, padding);
imageView.setScaleType(ImageView.ScaleType.FIT_XY);
Resources r = context.getResources();
Drawable[] layers = new Drawable[2];
layers[0] = r.getDrawable(GalImages[position]);
layers[1] = r.getDrawable(R.drawable.yourFrame);
LayerDrawable layerDrawable = new LayerDrawable(layers);
imageView.setImageDrawable(layerDrawable);
((ViewPager) container).addView(imageView, 0);
return imageView;
}
Edit 2
As some portions of your image gets hidden under the frame, you need to set the width and height of your image before using it in the ImageView.Have some calculations of what could be the best width and height combination for your image, such that it will fit exactly with your frame.For setting height and width of your image
#Override
public Object instantiateItem(ViewGroup container, int position) {
ImageView imageView = new ImageView(context);
int padding = context.getResources().getDimensionPixelSize(R.dimen.padding_small);
imageView.setPadding(padding, padding, padding, padding);
imageView.setScaleType(ImageView.ScaleType.FIT_XY);
Resources r = context.getResources();
Bitmap bmp = BitmapFactory.decodeResource(r, GalImages[position]);
int width=200;//set your width
int height=200;//set your height
Bitmap resizedbitmap = Bitmap.createScaledBitmap(bmp, width, height, true);
Drawable d = new BitmapDrawable(r,resizedbitmap);
Drawable[] layers = new Drawable[2];
layers[0] = d;
layers[1] = r.getDrawable(R.drawable.yourFrame);
LayerDrawable layerDrawable = new LayerDrawable(layers);
imageView.setImageDrawable(layerDrawable);
((ViewPager) container).addView(imageView, 0);
return imageView;
}
Using XML
Create a new Drawable XML file, let's call it mylayer.xml:
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/yourimage" />
<item android:drawable="#drawable/yourframe" />
</layer-list>
Now in your Activity set the image using that Drawable:
imageView.setImageDrawable(getResources().getDrawable(R.layout.mylayer));
I hope this gives you the basic idea for achieving what you want.