Programmatically Hiding the Android Soft Keyboard

Introduction

When developing an Android application, handling user input through EditText fields often requires managing the virtual keyboard. There are scenarios where you might want to programmatically hide or suppress the soft keyboard based on certain events, such as clicking a button or switching between tabs. This tutorial will guide you through different techniques for hiding the Android soft keyboard using Java and Kotlin.

Understanding InputMethodManager

The primary class used to interact with the software input methods in Android is InputMethodManager. It provides several methods to control the visibility of the soft keyboard, including:

• hideSoftInputFromWindow(): Hides the keyboard associated with a specific window token.
• toggleSoftInput(): Toggles the soft keyboard state between visible and hidden.

Method 1: Using hideSoftInputFromWindow()

This method is commonly used to hide the keyboard when a specific View loses focus. It requires obtaining a windowToken, which represents a reference to the window in which you want to hide the keyboard.

Java Example

To hide the soft keyboard, follow these steps:

1. Obtain the currently focused view.
2. Retrieve an instance of InputMethodManager.
3. Call hideSoftInputFromWindow() with the appropriate parameters.

// Check if no view has focus:
View view = this.getCurrentFocus();
if (view != null) {
    InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
    imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
}

Kotlin Example

In Kotlin, you can achieve the same functionality with slightly different syntax:

// Only runs if there is a view that is currently focused
this.currentFocus?.let { view ->
    val imm = getSystemService(Context.INPUT_METHOD_SERVICE) as? InputMethodManager
    imm?.hideSoftInputFromWindow(view.windowToken, 0)
}

Considerations

• Ensure you have access to a valid Context or use an Activity instance.
• If no view is focused, you may need to create a dummy view to obtain a window token.

Method 2: Using toggleSoftInput()

An alternative approach is using the toggleSoftInput() method. This can be particularly useful when you want to ensure that the keyboard is hidden implicitly without affecting explicit user requests for displaying it.

Java Example

InputMethodManager imm = (InputMethodManager) getSystemService(Activity.INPUT_METHOD_SERVICE);
imm.toggleSoftInput(InputMethodManager.HIDE_IMPLICIT_ONLY, 0);

Method 3: Configuring windowSoftInputMode

The windowSoftInputMode attribute in your AndroidManifest.xml can help manage keyboard behavior by default. Setting it to stateAlwaysHidden instructs the system not to show the soft keyboard automatically on focus events:

<activity
    android:name=".MyActivity"
    android:windowSoftInputMode="stateAlwaysHidden"/>

Note: This setting only affects initial focus and does not prevent keyboard display upon touch interactions.

Additional Tips

• Clear Focus: To avoid the keyboard reappearing when an app is brought from the background, clear focus on the view using view.clearFocus().

• Obtaining Window Tokens in Fragments: If no focused view is available (e.g., after switching fragments), obtain a window token using alternative methods:

  • For a fragment:

    View rootView = getView().getRootView();
    rootView.getWindowToken(); // Use this token with hideSoftInputFromWindow()
    

• Handling Multiple Views: When dealing with multiple views, such as TabHost, ensure you obtain the correct window token representing the current context or container.

Conclusion

Managing the soft keyboard programmatically in Android requires understanding how to interact with InputMethodManager and appropriately obtaining window tokens. Whether hiding the keyboard on specific events or configuring default behavior through manifest settings, these techniques provide a robust approach for handling user input experiences in your app. Always consider the context and ensure you have access to necessary resources like Context or Activity.