设置活动如何使用顶部的箭头导航回来

Question

嗨我已经创建了一个设置活动，当我在设置菜单中并按下手机的后退按钮时，我将被定向到“主屏幕”，这是正确的，但是当我按下设置菜单的顶部箭头时没有发生的事情，它似乎只是一个按钮。 请参阅imgur以查看我的意思。 在设置活动中返回箭头，按此处。 我在java代码中环顾四周，似乎找到了按钮？ 所有帮助都是app reciated !!

这是设置菜单的整个java文件。

 public class SettingsActivity extends AppCompatPreferenceActivity { /** * A preference value change listener that updates the preference's summary * to reflect its new value. */ private static Preference.OnPreferenceChangeListener sBindPreferenceSummaryToValueListener = new Preference.OnPreferenceChangeListener() { @Override public boolean onPreferenceChange(Preference preference, Object value) { String stringValue = value.toString(); if (preference instanceof RingtonePreference) { // For ringtone preferences, look up the correct display value // using RingtoneManager. if (TextUtils.isEmpty(stringValue)) { // Empty values correspond to 'silent' (no ringtone). preference.setSummary(R.string.pref_ringtone_silent); } else { Ringtone ringtone = RingtoneManager.getRingtone( preference.getContext(), Uri.parse(stringValue)); if (ringtone == null) { // Clear the summary if there was a lookup error. preference.setSummary(null); } else { // Set the summary to reflect the new ringtone display // name. String name = ringtone.getTitle(preference.getContext()); preference.setSummary(name); } } } else { // For all other preferences, set the summary to the value's // simple string representation. preference.setSummary(stringValue); } return true; } }; /** * Helper method to determine if the device has an extra-large screen. For * example, 10" tablets are extra-large. */ private static boolean isXLargeTablet(Context context) { return (context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) >= Configuration.SCREENLAYOUT_SIZE_XLARGE; } /** * Binds a preference's summary to its value. More specifically, when the * preference's value is changed, its summary (line of text below the * preference title) is updated to reflect the value. The summary is also * immediately updated upon calling this method. The exact display format is * dependent on the type of preference. * * @see #sBindPreferenceSummaryToValueListener */ private static void bindPreferenceSummaryToValue(Preference preference) { // Set the listener to watch for value changes. preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener); // Trigger the listener immediately with the preference's // current value. sBindPreferenceSummaryToValueListener.onPreferenceChange(preference, PreferenceManager .getDefaultSharedPreferences(preference.getContext()) .getString(preference.getKey(), "")); } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setupActionBar(); } /** * Set up the {@link android.app.ActionBar}, if the API is available. */ private void setupActionBar() { ActionBar actionBar = getSupportActionBar(); if (actionBar != null) { // Show the Up button in the action bar. actionBar.setDisplayHomeAsUpEnabled(true); } } /** * {@inheritDoc} */ @Override public boolean onIsMultiPane() { return isXLargeTablet(this); } /** * {@inheritDoc} */ @Override @TargetApi(Build.VERSION_CODES.HONEYCOMB) public void onBuildHeaders(List<Header> target) { loadHeadersFromResource(R.xml.pref_headers, target); } /** * This method stops fragment injection in malicious applications. * Make sure to deny any unknown fragments here. */ protected boolean isValidFragment(String fragmentName) { return PreferenceFragment.class.getName().equals(fragmentName) || GeneralPreferenceFragment.class.getName().equals(fragmentName); } /** * This fragment shows general preferences only. It is used when the * activity is showing a two-pane settings UI. */ @TargetApi(Build.VERSION_CODES.HONEYCOMB) public static class GeneralPreferenceFragment extends PreferenceFragment { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); addPreferencesFromResource(R.xml.pref_general); setHasOptionsMenu(true); // Bind the summaries of EditText/List/Dialog/Ringtone preferences // to their values. When their values change, their summaries are // updated to reflect the new value, per the Android Design // guidelines. bindPreferenceSummaryToValue(findPreference("example_text")); } @Override public boolean onOptionsItemSelected(MenuItem item) { int id = item.getItemId(); if (id == android.R.id.home) { startActivity(new Intent(getActivity(), SettingsActivity.class)); return true; } return super.onOptionsItemSelected(item); } } } 

我觉得这是按钮？

  @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setupActionBar(); } /** * Set up the {@link android.app.ActionBar}, if the API is available. */ private void setupActionBar() { ActionBar actionBar = getSupportActionBar(); if (actionBar != null) { // Show the Up button in the action bar. actionBar.setDisplayHomeAsUpEnabled(true); } } 

Answer 1

打开AndroidManifest.xml文件。 您需要使用以下内容为SettingsActivity定义父Activity ：

<meta-data android:name="android.support.PARENT_ACTIVITY"
  android:value=".MainActivity"/>

然后在你班上：

 /**
     * Set up the {@link android.app.ActionBar}, if the API is available.
     */
    private void setupActionBar() {
        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            // Show the Up button in the action bar.
            actionBar.setDisplayHomeAsUpEnabled(true);
            actionBar.setDisplayShowHomeEnabled(true);
        }
    }

如果您已将AppCompatActivity与Toolbar ，请检查此解决方案：

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);

// add back arrow to toolbar
if (getSupportActionBar() != null){
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setDisplayShowHomeEnabled(true);
}

如果您还想处理此事件或更改backButton图标，请转到： 工具栏Android上的显示后退箭头

编辑：将此代码添加到您的活动类：

@Override
public boolean onOptionsItemSelected(MenuItem item) { 
        switch (item.getItemId()) {
        case android.R.id.home: 
            onBackPressed();
            return true;
        }

    return super.onOptionsItemSelected(item);
}

希望它会有所帮助

Answer 2

在AndroidManifest.xml中，将其添加到Activity标记中

<meta-data android:name="android.support.PARENT_ACTIVITY" android:value=".HomeScreenActivity"/>

Answer 3

结合上面的答案

SettingsActivity.java

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getFragmentManager().beginTransaction().replace(android.R.id.content, new MainSettingsFragment()).commit();
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if (item.getItemId() == android.R.id.home) {
        onBackPressed();
    }
    return super.onOptionsItemSelected(item);
}

@Override
public void onBackPressed() {
    super.onBackPressed();
    this.finish();
    Intent intent = new Intent(this, MainActivity.class);
    startActivity(intent);
}

AndroidManifest.xml中

<activity android:name=".SettingsActivity"
    android:label="@string/title_settings">
    <meta-data android:name="android.support.PARENT_ACTIVITY"
    android:value=".MainActivity"/>
</activity>

Answer 4

你应该试试看。

@Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // handle arrow click here
        if (item.getItemId() == android.R.id.home) {
            finish(); // close this activity and return to preview activity (if there is any)`enter code here`
        }

        return super.onOptionsItemSelected(item);
    }