Android: ToggleButton changes state when ListView is scrolled

I created a program that has custom ListView with ToggleButton on each view then encountered onCheckedChanged() to be called whenever I scroll even I didn't click it and returns the opposite value of its current state.

In my listAdapter, I have below getView() function. Notice that I've added logger.

@Override
public View getView(int position, View convertView, ViewGroup parent) {
 final ListModel model = list.get(position);
 System.out.print("getView: "+ model.getPackageName());
 Holder holder = (Holder)view.getTag();
 // some other source here that I removed
 holder.toggleBtn.setChecked(model.getStatus());
 holder.toggleBtn.setOnCheckedChangeListener(new OnCheckedChangeListener() {
  public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
   System.out.print("onCheckedChanged: "+ model.getPackageName()+"="+isChecked);
  }
 });
 holder.index = model.getIndex();
 return view;
}

When the app runs (see Image 1), you'll see list of different applications from browser to email (after clock). Notice that the browser's ToogleButton is ON. Base on the logs below, all list item that is currently seen on the screen called getView() and NOT all list items.

Image 1: Screen is loaded from Browser to Email, though only a part of Email is seen.

getView: com.android.browser
getView: com.android.calculator2
getView: com.android.calendar
getView: com.android.chrome
getView: com.android.contacts
getView: com.android.deskclock
getView: com.android.email

When you scroll the ListView, it will call getView() again for the new list items that are seen on the screen. See Image 2, I scrolled down the screen to see Gallery and Camera. In the logs, it called the getView() for the two (2) newly seen list items; called onCheckChanged() of the Browser  even though I'm not clicking it and returns false (opposite of the earlier state).

Image 2: Scrolled down up to Camera

**SCROLLS DOWN
getView: com.android.gallery3d
getView: com.android.hwcamera
onCheckedChanged: com.android.browser=false

When I scrolled up again, you'll notice that it called again the getView() for the Browser; and called the onCheckChanged() of the Camera which returns true (opposite of earlier state).

**SCROLLS UP
getView: com.android.browser
onCheckedChanged: com.android.hwcamera=true

I noticed that whenever I scroll, the first item that was removed from screen (in the Image 1, it's the Browser; while in Image 2, it's the Camera and ignored Gallery) calls onCheckedChanged() returning the opposite value of ToggleButton's current state.

Solution:

Use onClick() instead of onCheckedChanged(). To get the current state, cast the view to ToggleButton and call isChecked(). See below:

holder.toggleBtn.setOnClickListener(new OnClickListener() {
 @Override
 public void onClick(View view) {
  Boolean isChecked = ((ToggleButton)view).isChecked();
  model.setStatus(isChecked);
 }
});

Now, even when you scroll it, you'll only get the right state of ToggleButton when it is clicked.

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Android : Install and Debug applications over WiFi

Connect your mobile phone to your laptop. Make sure that debugging mode is enabled and your phone is listed in Eclipse's Devices.

My phone is connected in my Eclipse via USB only.

Open command prompt and change directory to your android SDK\platform-tools.

cd <android-sdk path>\platform-tools

Run the following commands :

1. adb devices

   Take note of your phone's serial number

2. adb -s <phone's serial number> tcpip 5555

3. adb connect <phone's WiFi IP>

   
   You may get your phone's WiFi's IP address by going to Settings > Wi-Fi > press the Wi-Fi you're connected to > a pop-up will display with the IP at the bottom. 

If successful, cmd should print "connected to <phone's Wi-Fi IP>:5555" and see your phone connected in Eclipse's Devices.

My phone is now connected in my Eclipse via USB and Wi-Fi

You can now disconnect your phone in your PC and start running/debugging your applications via Wi-Fi

In the image below, you will see my actual sample using my phone.

Running all the commands

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