NullPointerException at ActionBarImplICS (using app compat) on long-press

Question

NullPointerException when long-press over field

compile 'com.android.support:appcompat-v7:19.1.+'

XML

<EditText
    android:id="@+id/field"
    style="@style/Field"
    android:textSize="20sp"
    android:hint="@string/hint"
    android:nextFocusDown="@+id/other"/>

Style

<style name="Field" parent="Theme.AppCompat.Light">
    <item name="android:layout_width">fill_parent</item>
    <item name="android:layout_height">wrap_content</item>
    <item name="android:textSize">14sp</item>
    <item name="android:textColor">@color/blue</item>
    <item name="android:singleLine">true</item>
    <item name="android:gravity">center_vertical</item>
    <item name="android:inputType">textCapCharacters|textNoSuggestions</item>
    <item name="android:imeOptions">actionNext</item>
    <item name="android:popupBackground">@color/white</item>
</style>

LogCat

java.lang.NullPointerException
     at android.support.v7.app.ActionBarImplICS.getThemedContext(ActionBarImplICS.java:302)
     at android.support.v7.app.ActionBarImplJB.getThemedContext(ActionBarImplJB.java:20)
     at android.support.v7.app.ActionBarActivityDelegate.getActionBarThemedContext(ActionBarActivityDelegate.java:208)
     at android.support.v7.app.ActionBarActivityDelegateICS.onActionModeStarted(ActionBarActivityDelegateICS.java:195)
     at android.support.v7.app.ActionBarActivityDelegateICS$WindowCallbackWrapper.onActionModeStarted(ActionBarActivityDelegateICS.java:359)
     at com.android.internal.policy.impl.PhoneWindow$DecorView.startActionMode(PhoneWindow.java:2437)
     at com.android.internal.policy.impl.PhoneWindow$DecorView.startActionModeForChild(PhoneWindow.java:2362)
     at android.view.ViewGroup.startActionModeForChild(ViewGroup.java:665)
     at android.view.ViewGroup.startActionModeForChild(ViewGroup.java:665)
     at android.view.ViewGroup.startActionModeForChild(ViewGroup.java:665)
     at android.view.ViewGroup.startActionModeForChild(ViewGroup.java:665)
     at android.view.View.startActionMode(View.java:4554)
     at android.widget.Editor.startSelectionActionMode(Editor.java:1551)
     at android.widget.Editor.performLongClick(Editor.java:859)
     at android.widget.TextView.performLongClick(TextView.java:8373)
     at android.view.View$CheckForLongPress.run(View.java:18441)
     at android.os.Handler.handleCallback(Handler.java:733)
     at android.os.Handler.dispatchMessage(Handler.java:95)
     at android.os.Looper.loop(Looper.java:136)
     at android.app.ActivityThread.main(ActivityThread.java:5102)
     at java.lang.reflect.Method.invokeNative(Native Method)
     at java.lang.reflect.Method.invoke(Method.java:515)
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
     at dalvik.system.NativeStart.main(Native Method)

Answer 1

The ActionBar is null. That's because you're using an activity without a title (and thus also without an actionbar):

requestWindowFeature(Window.FEATURE_NO_TITLE);

There are two ways to fix it.

Simple:
Make YourActivity NOT extends ActionBarActivity but normal Activity.

More difficult:
Make transparent ActionBar with no title, no icon, no home button etc. How to do this? First, define ActionBar style and new theme that extends YourAppTheme:

<!-- Your App Theme-->
<style name="YourAppTheme.Light" parent="@style/Theme.AppCompat.Light">
    <...>
</style>

<!-- Transparent ActionBar Style -->
<style name="YourAppTheme.Light.ActionBar.Transparent" parent="@style/Widget.AppCompat.Light.ActionBar">
    <item name="android:background">@android:color/transparent</item>
    <item name="background">@android:color/transparent</item>
</style>

<!-- Fullscreen Activity Theme -->
<style name="YourAppTheme.FullScreen.Light" parent="@style/YourAppTheme.Light">
    <item name="android:actionBarStyle">@style/YourAppTheme.Light.ActionBar.Transparent</item>
    <item name="actionBarStyle">@style/YourAppTheme.Light.ActionBar.Transparent</item>
    <item name="android:windowIsTranslucent">true</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:backgroundDimEnabled">false</item>
    <item name="android:windowActionBarOverlay">true</item>
    <item name="windowActionBarOverlay">true</item>
</style>

Next, set this theme to your fullscreen activity:

<activity
    android:name="your.package.name.YourFullscreenActivity"
    android:label="@string/app_name"
    android:theme="@style/YourAppTheme.FullScreen.Light" />

Finally, add following lines to YourFullscreenActivity#onCreate method:

getSupportActionBar().setDisplayHomeAsUpEnabled(false);
getSupportActionBar().setDisplayShowHomeEnabled(false);
getSupportActionBar().setDisplayShowTitleEnabled(false); 

I hope it will help.

Answer 2

I think I have a better solution to this issue.

Remove requestWindowFeature(Window.FEATURE_NO_TITLE); from activity and <item name="android:windowNoTitle">true</item> from activity theme.

To your activity code add:

To onCreate() method

View actionBar = getActionBarView();
if (actionBar != null) {
    actionBar.setVisibility(View.GONE);
}

To activity class:

public View getActionBarView() {
    Window window = getWindow();
    View v = window.getDecorView();
    int resId;

    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB) {
        resId = getResources().getIdentifier(
                "action_bar_container", "id", getPackageName());
    } else {
        resId = Resources.getSystem().getIdentifier(
                "action_bar_container", "id", "android");
    }
    if (resId != 0) {
        return v.findViewById(resId);
    } else {
        return null;
    }
}

@Override
public void onSupportActionModeStarted(ActionMode mode) {
    super.onSupportActionModeStarted(mode);
    View actionBar = getActionBarView();
    if (actionBar != null) {
        actionBar.setVisibility(View.VISIBLE);
    }
}

@Override
public void onSupportActionModeFinished(ActionMode mode) {
    super.onSupportActionModeFinished(mode);
    View actionBar = getActionBarView();
    if (actionBar != null) {
        actionBar.setVisibility(View.GONE);
    }
}

This is remove action bar and at the same time allows you to manipulate text in edit text with action mode buttons.

Cheers