Android片段后栈
我在我的项目中使用了多个片段。我想保存一个片段的状态,当我回到这里时恢复这个状态。在这个片段中,我展示了多个在点击按钮时改变的图像。为此,我使用以下代码:Android片段后栈,android,android-fragments,back-stack,savestate,fragment-backstack,Android,Android Fragments,Back Stack,Savestate,Fragment Backstack,我在我的项目中使用了多个片段。我想保存一个片段的状态,当我回到这里时恢复这个状态。在这个片段中,我展示了多个在点击按钮时改变的图像。为此,我使用以下代码: String backStateName = fragment.getClass().getName(); FragmentManager fragmentManager = getSupportFragmentManager(); boolean fragmentPopped = fragmentManager.popBackStackIm
String backStateName = fragment.getClass().getName();
FragmentManager fragmentManager = getSupportFragmentManager();
boolean fragmentPopped = fragmentManager.popBackStackImmediate(backStateName, 0);
if (!fragmentPopped) {
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragment);
fragmentTransaction.addToBackStack(backStateName);
fragmentTransaction.commit();
}
它工作正常&它保存状态,但不显示以前的图像
任何帮助、建议或指导都将不胜感激。谢谢。您可以使用以下代码。 当您从上一个片段返回时,它不会重新加载片段:
if (!fragmentPopped) {
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.hide(getFragmentManager().findFragmentById(R.id.container_body));
fragmentTransaction.add(R.id.container_body, fragment);
fragmentTransaction.addToBackStack(backStateName);
fragmentTransaction.commit();
}
你可以用
fragmentTransaction.hide(getFragmentManager().findFragmentById(R.id.frame_container));
fragmentTransaction.add(R.id.frame_container, fragment);
fragmentTransaction.addToBackStack(null);
而不是
fragmentTransaction.replace(R.id.container_body, fragment);
fragmentTransaction.addToBackStack(backStateName);
我正在尝试碎片列表 初始化框架列表 背压 对于后移除堆栈
我在这段代码中使用了多个片段。请将这段代码放在您的
main活动中
@Override
public void onBackPressed() {
/* Fragment fragment = new SettingActivity();
String title = getString(R.string.app_name);
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragment);
fragmentTransaction.commit();
// set the toolbar title
getSupportActionBar().setTitle(title);*/
//Log.e("title:", getTitle().toString());
getSupportActionBar().setTitle("Home");
//Log.e("title:", getTitle().toString());
if (!getTitle().toString().equals("Home")) {
Fragment fragment = new Activity_category();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container_body, fragment).commit();
this.setTitle("Home");
} else {
super.onBackPressed();
}
}
愿这对你有帮助 如果您可以在打开片段时将图像保存在android磁盘缓存中,并通过从磁盘缓存读取来显示图像,则可能会解决您的问题。请按照下面的谷歌链接,了解如何在磁盘缓存中保存图像
以下是我认为你应该遵循的步骤
将图像存储在磁盘缓存中
将ImagesFragment附加到活动从磁盘缓存读取图像并显示它们
当片段从backbackback中弹出时,您的代码将自动从磁盘缓存中读取图像
希望这能有所帮助。您将片段放在后堆栈中,这样就不存在片段的错误,您需要在图像库中进行检查。我可以知道你在用哪个图书馆吗。我建议使用毕加索图书馆。我也在使用它,并在片段中获得状态保存的图像
@Override
public void onBackPressed() {
/* Fragment fragment = new SettingActivity();
String title = getString(R.string.app_name);
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragment);
fragmentTransaction.commit();
// set the toolbar title
getSupportActionBar().setTitle(title);*/
//Log.e("title:", getTitle().toString());
getSupportActionBar().setTitle("Home");
//Log.e("title:", getTitle().toString());
if (!getTitle().toString().equals("Home")) {
Fragment fragment = new Activity_category();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container_body, fragment).commit();
this.setTitle("Home");
} else {
super.onBackPressed();
}
}
您可以使用下面的代码进行循环导航。您甚至可以访问两个片段,反之亦然
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
hideLastFragment(fragmentTransaction);
fragmentTransaction.add(R.id.profile_fragmentContainer, youfFragment, fragmentTagName).addToBackStack(fragmentTagName);
fragmentTransaction.commitAllowingStateLoss();
/**
* To hide the last fragment
*
* @param fragmentTransaction FragmentTransaction
*/
public void hideLastFragment(FragmentTransaction fragmentTransaction) {
final int backStackCount = getSupportFragmentManager().getBackStackEntryCount() - 1;
if (backStackCount >= 0) {
String fragmentName = getSupportFragmentManager().getBackStackEntryAt(backStackCount).getName();
Fragment lastFragment = getSupportFragmentManager().findFragmentByTag(fragmentName);
fragmentTransaction.hide(lastFragment);
}
}
fragmentTransaction.addToBackStack(空)代码>为什么不使用glide进行图像处理?它会将图像保存在缓存中
final android.app.FragmentManager fm = getFragmentManager();
fm.addOnBackStackChangedListener(new android.app.FragmentManager.OnBackStackChangedListener() {
@Override
public void onBackStackChanged() {
if (getSupportFragmentManager().getBackStackEntryCount() ==0) {
// dLayout.closeDrawers();
finish();
}
else
{
// dLayout.closeDrawers();
}
}
});
@Override
public void onBackPressed() {
/* Fragment fragment = new SettingActivity();
String title = getString(R.string.app_name);
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container_body, fragment);
fragmentTransaction.commit();
// set the toolbar title
getSupportActionBar().setTitle(title);*/
//Log.e("title:", getTitle().toString());
getSupportActionBar().setTitle("Home");
//Log.e("title:", getTitle().toString());
if (!getTitle().toString().equals("Home")) {
Fragment fragment = new Activity_category();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container_body, fragment).commit();
this.setTitle("Home");
} else {
super.onBackPressed();
}
}
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
hideLastFragment(fragmentTransaction);
fragmentTransaction.add(R.id.profile_fragmentContainer, youfFragment, fragmentTagName).addToBackStack(fragmentTagName);
fragmentTransaction.commitAllowingStateLoss();
/**
* To hide the last fragment
*
* @param fragmentTransaction FragmentTransaction
*/
public void hideLastFragment(FragmentTransaction fragmentTransaction) {
final int backStackCount = getSupportFragmentManager().getBackStackEntryCount() - 1;
if (backStackCount >= 0) {
String fragmentName = getSupportFragmentManager().getBackStackEntryAt(backStackCount).getName();
Fragment lastFragment = getSupportFragmentManager().findFragmentByTag(fragmentName);
fragmentTransaction.hide(lastFragment);
}
}