我想请求一些帮助:在我的应用中,我只有一个活动,PreferenceActivity
(不需要其他活动,它只是一个简单的后台同步应用,所以{{1是主/启动器)。在用户设置首选项之后,检查PrefsActivity
,然后启动(或停止)服务。在开始时,会出现一个对话框。
但问题出在这里:如果用户按下(离开活动),再次启动它,然后尝试检查checkBoxPreference
。checkBoxPref
崩溃。对话框没有显示。我不知道为什么,以及如何解决它。
这段代码与那部分完全相同,是什么给我带来了问题:
PrefsActivity.java:
prefsactivity
的prefs.xml:
package is.it.works;
// imports .....
public class PrefsActivity extends PreferenceActivity implements OnSharedPreferenceChangeListener {
SharedPreferences prefs;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.prefs);
prefs = PreferenceManager.getDefaultSharedPreferences(this);
prefs.registerOnSharedPreferenceChangeListener(this);
}// onCreate
@Override
public void onSharedPreferenceChanged(SharedPreferences preferences, String key) {
if (key.equals("checkTest")) {
showDialog(1);
}
if (key.equals("cancel")) {
dismissDialog(1);
}
}// onSPC
@Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case 1: {
ProgressDialog dialog = new ProgressDialog(this);
dialog.setMessage("press back twice, start the app again, and click checkbox...");
dialog.setIndeterminate(true);
dialog.setCancelable(true);
dialog.setOnCancelListener(new OnCancelListener() {
@Override
public void onCancel(DialogInterface dialog) {
prefs.edit().putBoolean("cancel", false).commit();
}
});
return dialog;
}// case
}// switch
return null;
}// onCreateDialog
}// PrefsActivity
和清单:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<CheckBoxPreference android:key="checkTest" android:title="test" />
</PreferenceScreen>
LogCat错误:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="is.it.works" android:versionCode="1" android:versionName="1.0">
<uses-sdk android:minSdkVersion="4" />
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".PrefsActivity" android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
经过googleing,我认为,错误的部分是09-14 10:34:34.472: ERROR/AndroidRuntime(281): Uncaught handler: thread main exiting due to uncaught exception
09-14 10:34:34.502: ERROR/AndroidRuntime(281): android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@43756de8 is not valid; is your activity running?
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.view.ViewRoot.setView(ViewRoot.java:456)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.view.Window$LocalWindowManager.addView(Window.java:409)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.app.Dialog.show(Dialog.java:238)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.app.Activity.showDialog(Activity.java:2413)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at is.it.works.PrefsActivity.onSharedPreferenceChanged(PrefsActivity.java:27)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.app.ApplicationContext$SharedPreferencesImpl$EditorImpl.commit(ApplicationContext.java:2727)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.preference.Preference.tryCommit(Preference.java:1199)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.preference.Preference.persistBoolean(Preference.java:1404)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.preference.CheckBoxPreference.setChecked(CheckBoxPreference.java:155)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.preference.CheckBoxPreference.onClick(CheckBoxPreference.java:143)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.preference.Preference.performClick(Preference.java:811)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.preference.PreferenceScreen.onItemClick(PreferenceScreen.java:190)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.widget.AdapterView.performItemClick(AdapterView.java:284)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.widget.ListView.performItemClick(ListView.java:3246)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.widget.AbsListView$PerformClick.run(AbsListView.java:1635)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.os.Handler.handleCallback(Handler.java:587)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.os.Handler.dispatchMessage(Handler.java:92)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.os.Looper.loop(Looper.java:123)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at android.app.ActivityThread.main(ActivityThread.java:4203)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at java.lang.reflect.Method.invokeNative(Native Method)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at java.lang.reflect.Method.invoke(Method.java:521)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
09-14 10:34:34.502: ERROR/AndroidRuntime(281): at dalvik.system.NativeStart.main(Native Method)
09-14 10:34:34.522: INFO/Process(52): Sending signal. PID: 281 SIG: 3
09-14 10:34:34.532: INFO/dalvikvm(281): threadid=7: reacting to signal 3
09-14 10:34:34.592: INFO/dalvikvm(281): Wrote stack trace to '/data/anr/traces.txt'
09-14 10:34:38.533: DEBUG/dalvikvm(107): GC freed 437 objects / 21560 bytes in 136ms
09-14 10:34:39.183: INFO/global(175): Default buffer size used in BufferedReader constructor. It would be better to be explicit if an 8k-char buffer is required.
09-14 10:34:44.632: INFO/global(175): Default buffer size used in BufferedReader constructor. It would be better to be explicit if an 8k-char buffer is required.
09-14 10:34:47.412: INFO/Process(281): Sending signal. PID: 281 SIG: 9
09-14 10:34:47.472: INFO/ActivityManager(52): Process is.it.works (pid 281) has died.
09-14 10:34:47.492: INFO/WindowManager(52): WIN DEATH: Window{4394f638 is.it.works/is.it.works.PrefsActivity paused=false}
。导致ProgressDialog dialog = new ProgressDialog(this);
更改。但是将其更改为this
或getApplicationContext()
并没有帮助,问题仍然存在。
请告诉我为什么会发生这种情况,可能是什么解决方案!谢谢!
我被卡住了,现在我不知道......
答案 0 :(得分:81)
我有一个非常类似的问题(让我来到这里)并找到了一个非常简单的解决方案。虽然我的代码不同,但应该很容易适应。这是我的修复:
public void showBox() {
mActive = true;
if (! ((Activity) mContext).isFinishing()) {
mDialogBox.show();
}
}
因此,在问题的示例代码中,修复将是(猜测):
@Override
public void onSharedPreferenceChanged(SharedPreferences preferences, String key) {
if (key.equals("checkTest")) {
if (! this.isFinishing()) {
showDialog(1);
}
}
if (key.equals("cancel")) {
dismissDialog(1);
}
}// onSPC
答案 1 :(得分:4)
也许您没有关闭或取消注册活动中的某些内容。在这种情况下,请尝试在onDestroy上取消注册broadcastreceiver。
答案 2 :(得分:1)
在将崩溃跟踪引入项目之后,我注意到这个问题经常出现,并且在整个项目中发现同样的修复工作以消除崩溃:
示例:
MyActivity extends Activity {
ProgressDialog mProgressDialog;
AlertDialog mAlertDialog;
@Override
public void onCreate(Bundle savedInstanceState) {
mProgressDialog = new ProgressDialog(MyActivity.this);
mAlertDialog = new AlertDialog.Builder(MyActivity.this).show();
}
@Override
public void onDestroy() {
super.onDestroy();
if(mProgressDialog != null) {
mProgressDialog.dismiss();
}
if(mAlertDialog != null) {
mAlertDialog.dismiss();
}
}
错误消息显示“无法添加窗口”是误导性的,因为我发现当您离开活动时发生错误并且传递给您的Dialog的上下文已经死亡。
答案 3 :(得分:1)
对我来说,这解决了问题..检查对话框是否为空或不显示,如果是,则再次创建。
// create alert dialog
if (enableNetworkDialog == null || !enableNetworkDialog.isShowing())
enableNetworkDialog = alertDialogBuilder.create();
if (context instanceof AppCompatActivity && !((AppCompatActivity) context).isFinishing())
enableNetworkDialog.show();
答案 4 :(得分:0)
顶级解决方案只能防止崩溃。对我来说问题是我提到了一个错误的context
来显示警告对话框。传递正确的context
后,问题就解决了。
答案 5 :(得分:0)
这通常是由于您的应用尝试使用先前完成的“活动”作为上下文来显示对话框。然后在显示对话框之前,检查活动是否被其他一些应用程序或其他触发器未关闭
if (!isFinishing()) {
//showdialog here
}