CODEWITHSUNDEEP
javaandroidandroid-studio
Mayank Panchal
Mayank Panchal

Reputation: 37

Caused by: java.lang.ClassCastException: com.example.mayank.sunshine.SettingsActivity cannot be cast to android.app.Activity

package com.example.mayank.sunshine;

import android.os.Bundle;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.PreferenceFragment;
import android.preference.PreferenceManager;

/**
 * A {@link PreferenceActivity} that presents a set of application settings.
 * <p>
 * See <a href="http://developer.android.com/design/patterns/settings.html">
 * Android Design: Settings</a> for design guidelines and the <a
 * href="http://developer.android.com/guide/topics/ui/settings.html">Settings
 * API Guide</a> for more information on developing a Settings UI.
 */
public class SettingsActivity extends PreferenceFragment
        implements Preference.OnPreferenceChangeListener {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Add 'general' preferences, defined in the XML file
        addPreferencesFromResource(R.xml.pref_general);

        // For all preferences, attach an OnPreferenceChangeListener so the UI summary can be
        // updated when the preference changes.
        bindPreferenceSummaryToValue(findPreference(getString(R.string.pref_location_key)));
    }

    /**
     * Attaches a listener so the summary is always updated with the preference value.
     * Also fires the listener once, to initialize the summary (so it shows up before the value
     * is changed.)
     */
    private void bindPreferenceSummaryToValue(Preference preference) {
        // Set the listener to watch for value changes.
        preference.setOnPreferenceChangeListener(this);

        // Trigger the listener immediately with the preference's
        // current value.
        onPreferenceChange(preference,
                PreferenceManager
                        .getDefaultSharedPreferences(preference.getContext())
                        .getString(preference.getKey(), ""));
    }

    @Override
    public boolean onPreferenceChange(Preference preference, Object value) {
        String stringValue = value.toString();

        if (preference instanceof ListPreference) {
            // For list preferences, look up the correct display value in
            // the preference's 'entries' list (since they have separate labels/values).
            ListPreference listPreference = (ListPreference) preference;
            int prefIndex = listPreference.findIndexOfValue(stringValue);
            if (prefIndex >= 0) {
                preference.setSummary(listPreference.getEntries()[prefIndex]);
            }
        } else {
            // For other preferences, set the summary to the value's simple string representation.
            preference.setSummary(stringValue);
        }
        return true;
    }

}

The above code shows the following error: Caused by: java.lang.ClassCastException: com.example.mayank.sunshine.SettingsActivity cannot be cast to android.app.Activity

The code previously had "SettingsActivity extends PreferenceActivity", but some of the functions are shown as deprecated, and I was guided to use the PreferenceFragment class instead, so on changing the parent class, the error started popping up. Also, the following part of manifest file shows error in android:name=".SettingsActivity"

<activity
    android:name=".SettingsActivity"
    android:label="@string/title_activity_settings"
    android:parentActivityName=".MainActivity"
    android:theme="@style/AppTheme.NoActionBar" >
    <meta-data
        android:name="android.support.PARENT_ACTIVITY"
        android:value="com.example.mayank.sunshine.MainActivity" />
</activity>

Upvotes: 0

Views: 833

Answers (1)

CommonsWare
CommonsWare

Reputation: 1006634

The above code shows the following error: Caused by: java.lang.ClassCastException: com.example.mayank.sunshine.SettingsActivity cannot be cast to android.app.Activity

That is because your SettingsActivity does not have Activity in its inheritance chain. SettingsActivity inherits from Fragment, which inherits from Object.

The code previously had "SettingsActivity extends PreferenceActivity", but this class is deprecated in newer APIs

PreferenceActivity is not deprecated in any version of Android, through API Level 23.

Upvotes: 1

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