我的应用程序基本上包含两个活动,一个main-activity和一个settings-activity。
设置-活动由
Intent launchNewIntent = new Intent(MainActivity.this,SettingsActivity.class);
startActivityForResult(launchNewIntent, 0);
,其中包含一些片段。我使用向上导航,它在片段之间的设置活动中完美地工作,但是当按下后退按钮时我没有返回到我的主要活动。setDisplayHomeAsUpEnabled 命令在我的设置活动中,因为当我将它放置在我的主要活动中时,它并没有帮助解决我的问题。
在我的清单中,我已将 main-activity 声明为 settings-activity的父活动。
那我该怎么办?- 非常感谢!
我的主要活动
package user.example;
import android.app.FragmentManager;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.view.View;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
Intent launchNewIntent = new Intent(MainActivity.this,SettingsActivity.class);
startActivityForResult(launchNewIntent, 0);
return true;
}
return super.onOptionsItemSelected(item);
}
}
我的 SettingsActivity :(我省略了片段,但重现了相同的错误)
package user.example;
import android.support.v7.app.ActionBar;
public class SettingsActivity extends AppCompatPreferenceActivity {
private void setupActionBar() {
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
@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);
bindPreferenceSummaryToValue(findPreference("example_text"));
bindPreferenceSummaryToValue(findPreference("example_list"));
}
@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);
}
}
}
AppCompatPreferenceActivity:(由 Settings.activity 启动)
package user.example;
import android.content.res.Configuration;
import android.os.Bundle;
import android.preference.PreferenceActivity;
import android.support.annotation.LayoutRes;
import android.support.annotation.Nullable;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatDelegate;
import android.support.v7.widget.Toolbar;
import android.view.MenuInflater;
import android.view.View;
import android.view.ViewGroup;
public abstract class AppCompatPreferenceActivity extends PreferenceActivity {
private AppCompatDelegate mDelegate;
@Override
protected void onCreate(Bundle savedInstanceState) {
getDelegate().installViewFactory();
getDelegate().onCreate(savedInstanceState);
super.onCreate(savedInstanceState);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
getDelegate().onPostCreate(savedInstanceState);
}
public ActionBar getSupportActionBar() {
return getDelegate().getSupportActionBar();
}
public void setSupportActionBar(@Nullable Toolbar toolbar) {
getDelegate().setSupportActionBar(toolbar);
}
@Override
public MenuInflater getMenuInflater() {
return getDelegate().getMenuInflater();
}
@Override
public void setContentView(@LayoutRes int layoutResID) {
getDelegate().setContentView(layoutResID);
}
@Override
public void setContentView(View view) {
getDelegate().setContentView(view);
}
@Override
public void setContentView(View view, ViewGroup.LayoutParams params) {
getDelegate().setContentView(view, params);
}
@Override
public void addContentView(View view, ViewGroup.LayoutParams params) {
getDelegate().addContentView(view, params);
}
@Override
protected void onPostResume() {
super.onPostResume();
getDelegate().onPostResume();
}
@Override
protected void onTitleChanged(CharSequence title, int color) {
super.onTitleChanged(title, color);
getDelegate().setTitle(title);
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
getDelegate().onConfigurationChanged(newConfig);
}
@Override
protected void onStop() {
super.onStop();
getDelegate().onStop();
}
@Override
protected void onDestroy() {
super.onDestroy();
getDelegate().onDestroy();
}
public void invalidateOptionsMenu() {
getDelegate().invalidateOptionsMenu();
}
private AppCompatDelegate getDelegate() {
if (mDelegate == null) {
mDelegate = AppCompatDelegate.create(this, null);
}
return mDelegate;
}
}